Dietary carbohydrates: role of quality and quantity in chronic disease

Cross-sectional association between the isocaloric replacement of carbohydrates with protein and fat in relation to fat compartments distribution and hepatic lipid content in recent-onset type 1 and type 2 diabetes

BACKGROUND

Diets restricted in carbohydrates may be beneficial for diabetes management. However, without reducing energy intake, carbohydrate restriction results in increased protein and fat intake. Understanding how this macronutrient substitution is associated with adipose tissue distribution is important to prevent diabetes progression. Therefore, the aim was to investigate the isocaloric substitution of carbohydrates with fat and protein in relation to subcutaneous (SAT) and visceral adipose tissue (VAT) and hepatic lipid (HL) content in individuals with recent-onset type 1 (T1D) and type 2 diabetes (T2D), accounting for macronutrient quality.

METHODS

This cross-sectional analysis includes participants with T1D (n = 137) and T2D (n = 170) from the German Diabetes Study (GDS). Dietary macronutrient intake was derived from dietary information assessed with a validated food frequency questionnaire. SAT and VAT were measured with magnetic resonance (MR) imaging, while HL content with 1H MR spectroscopy. Isocaloric substitution analyses based on multivariable linear regression models were conducted to examine the replacement of total and higher glycemic index (GI) carbohydrates in energy percent (En%) with total fat, monounsaturated (MUFA), polyunsaturated (PUFA), and saturated fatty acids (SFA), and protein in regard to SAT, VAT and HL content.

RESULTS

In individuals with T1D, substituting carbohydrates with total fat was not associated with SAT, while substituting carbohydrates with protein demonstrated higher SAT [β (95% CI) per 5 En%: 3100 cm3 (25, 6200)]. In individuals with T2D, replacing carbohydrates with total fat or protein showed no association with SAT and VAT. However, substituting carbohydrates with PUFA was associated with lower VAT [-970 cm3 (-1900, -40)] and HL content [-3.3% (-6.9, 0.4)], while replacing carbohydrates with SFA was associated with higher HL content [2.4% (-0.6, 5.4)]. Substituting carbohydrates with protein was associated with lower HL content in individuals with T2D [-2.4% (-4.9, 0.0)], mainly driven by plant-based protein. There were no substantial differences between the replacement of total and higher GI carbohydrates.

CONCLUSIONS

The quality of substituted nutrients may play an important role for adipose tissue and HL accumulation in individuals with T2D. Particularly, integrating PUFAs and plant-based proteins into the diet seems beneficial for VAT and HL content.

FTO rs9939609 polymorphism is associated with dietary quality in Korean females

PURPOSE

Variation in fat mass and obesity-associated gene (FTO) is a critical risk factor in the etiology of obesity. FTO is associated with preference and sensory perception of nutrients and dietary intake. However, the effect of genetic variation on overall dietary quality has not yet been fully elucidated. This study examined whether FTO rs9939609 (T > A) was associated with dietary quality in Koreans.

METHODS

Data of 46,928 individuals from the Korean Genome and Epidemiology Study were analyzed according to FTO rs9939609 genotype, general characteristics, and diet quality based on the Korean Healthy Eating Index (KHEI), employing sex- and age-stratified approaches.

RESULTS

The FTO genotype did not significantly influence overall diet quality; however, female carriers of the obesity risk allele A (TA + AA) showed significantly higher KHEI scores for balance of energy nutrient consumption, especially for carbohydrate ratio (2.00 ± 1.99 versus 1.90 ± 1.98, Padjusted <0.001) and fat ratio (2.87 ± 2.15 versus 2.76 ± 2.17, Padjusted <0.001) than A-allele non-carriers (TT). Furthermore, when the females were grouped based on their median age (51 years), such an association between the FTO genotype and energy nutrient ratio was only evident in the younger group. However, such an effect of the genetic variant on diet quality and energy nutrient consumption was not evident in males, and the interactive effect of FTO and sex and age was not statistically significant.

CONCLUSION

The FTO rs9939609 (T > A) polymorphism is associated with dietary quality, particularly influencing the balance of energy nutrient intake in Korean females.

Higher dietary glycemic index, but not glycemic load, is associated with increased risk of ulcerative colitis: a prospective cohort study

BACKGROUND AND AIMS

Total carbohydrate intake has been inconsistently associated with inflammatory bowel disease (IBD) risk in previous epidemiological studies. We aimed to evaluate the effects of glycemic index and glycemic load, 2 main indicators for measuring the quality and quantity of carbohydrates, on the risk of IBD subtypes (ie, Crohn's disease [CD] and ulcerative colitis [UC]).

METHODS

We included 121 148 UK Biobank participants without IBD at baseline, and collected dietary information from a validated web-based 24-hour dietary recall questionnaire. Overall dietary glycemic index and glycemic load were estimated. Cox proportional hazard models were used to calculate multivariable-adjusted hazard ratios (HRs) and 95% CIs. Substitution analyses were conducted to test associations after replacing medium- or high-glycemic-index foods with low-glycemic-index foods.

RESULTS

During a median follow-up of 10.6 years, 133 incident CD and 335 incident UC cases were identified. Dietary glycemic index was associated with UC but not CD. The HR of UC was 1.13 (95% CI, 1.01-1.27) per 1-SD increment and 1.46 (95% CI, 1.07-1.99) for the highest versus lowest quartile of glycemic index. Replacing medium or medium- and high-glycemic-index foods with low-glycemic-index foods was associated with a lower risk of UC. No significant associations were found between dietary glycemic load with risk of CD and UC.

CONCLUSIONS

A higher dietary glycemic index, but not glycemic load, is associated with an increased risk of UC, underscoring the importance of considering glycemic index in dietary recommendations for UC prevention.

Myths and Facts Regarding Low-Carbohydrate Diets

As the prevalence of chronic diseases persists at epidemic proportions, health practitioners face ongoing challenges in providing effective lifestyle treatments for their patients. Even for those patients on GLP-1 agonists, nutrition counseling remains a crucial strategy for managing these conditions over the long term. This paper aims to address the concerns of patients and practitioners who are interested in a low-carbohydrate or ketogenic diet, but who have concerns about its efficacy, safety, and long-term viability. The authors of this paper are practitioners who have used this approach and researchers engaged in its study. The paper reflects our opinion and is not meant to review low-carbohydrate diets systematically. In addressing common concerns, we hope to show that this approach has been well researched and can no longer be seen as a "fad diet" with adverse health effects such as impaired renal function or increased risk of heart disease. We also address persistent questions about patient adherence, affordability, and environmental sustainability. This paper reflects our perspective as clinicians and researchers engaged in the study and application of low-carbohydrate dietary interventions. While the paper is not a systematic review, all factual claims are substantiated with citations from the peer-reviewed literature and the most rigorous and recent science. To our knowledge, this paper is the first to address potential misconceptions about low-carbohydrate and ketogenic diets comprehensively.

The associations between evening eating and quality of energy and macronutrients and obesity: the National Health and Nutrition Examination Survey (NHANES), 2003-2016

BACKGROUND

This study aimed to investigate the associations between evening eating and quality of energy and macronutrients and obesity among U.S. adults.

SUBJECTS/METHODS

This study adopted the data from the National Health and Nutrition Examination Survey (2003-2016), which involved a total of 27,911 participants. The differences in the ratios of energy and macronutrients with it is subgroups at dinner versus breakfast (ΔRatio) were categorized into quartiles. The differences in the consumption of 17 types of food at dinner versus breakfast (ΔFoods) were considered as continuous variables. Body mass index (BMI) and waist circumference (WC) were used to define general obesity (30.0 ≤ BMI < 40.0), morbid obesity (BMI ≥ 40.0), and abdominal obesity (WC > 102 cm for men or WC > 88 cm for women). Multiple logistic and linear regression models were developed.

RESULTS

After a variety of covariates were adjusted, participants in the highest quartile (higher energy/macronutrient intake at dinner than breakfast) of the ΔRatio in terms of energy were positively associated with morbid obesity compared with those in the lowest quartile (ORΔRatio of energy 1.27; 95% CI 1.01;1.61) from fat (ORΔRatio of fat 1.27, 95% CI 1.01;1.60); saturated fatty acids(ORΔRatio of SFA 1.27, 95% CI 1.01;1.59) and unsaturated fatty acids (ORΔRatio of USFA 1.28, 95% CI 1.02;1.5). The highest quartile of the ΔRatio of low-quality carbohydrates was associated with increased odds of abdominal obesity (ORΔRatio of low-quality carbohydrates 1.16; 95%CI 1.03-1.31). Moreover, the ΔRatio of low-quality carbohydrates was significantly positively associated with BMI (coefficient: 0.562, 95% CI: 0.217-0.907). ΔFoods, including whole fruits, other starchy vegetables, added sugars, poultry, dairy, and nuts, were positively associated with obesity.

CONCLUSIONS

In conclusion, with this nationally representative sample of U.S adults, this study demonstrated that excessive intake of energy at dinner than breakfast during a day was associated with a greater risk of obesity, mainly from low-quality carbohydrates, fat, SFAs, and USFA. This study emphasized the importance of diet quality and evening eating in the prevention of obesity.

Fruit Carbohydrates and Their Impact on the Glycemic Index: A Study of Key Determinants

Background: Fruits are a convenient and natural source of carbohydrates that can rapidly affect blood sugar levels and the glycemic index (GI). The GI plays a crucial role in the management of chronic diseases, including diabetes, obesity, hyperglycemia, and diet-related illnesses. Despite there being several health benefits linked with consuming fruits, it remains unclear which specific components of fruits are the key determinants that significantly influence the GI. Methods: This study retrospectively examined the relationship between different types of carbohydrates and the GI of various fruits to determine their correlation. The fruits' sugar and fiber contents were identified from available public databases, the U.S. Department of Agriculture (USDA), FooDB, PubMed, and published sources. Results: Previously, the GI was determined by the available carbohydrates, which include different types of sugar. In this study, individual hexose sugars, along with the total carbohydrates and dietary fiber, were examined. The results indicated a strong correlation between fructose and the GI, whereas glucose and total glucose did not exhibit such a correlation. The total carbohydrate-to-fiber ratio displayed a stronger correlation (R = 0.57 and p > 0.0001) with the GI compared to glucose alone (R = 0.37; p = 0.01) or the total glucose (R = 0.45; p = 0.0009) with the consideration of fiber, while the scattering of data points around the regression line suggested that factors beyond the total carbohydrate and fiber also contribute to determining the GI. Conclusions: This study demonstrated that individual hexose sugars, especially fructose, significantly influence the GI. These findings suggest that the carbohydrate-to-fiber ratio may offer a more accurate and reliable metric for determining the GI than traditional methods. Further research is warranted to investigate the specific contribution of dietary fiber components, fruit texture, micronutrients, vitamins, genetic predispositions, gut microbiota, and the body's physiological status to gain a deeper understanding of GI regulation.

Associations of carbohydrate quality and cardiovascular risk factors vary among diabetes subtypes

BACKGROUND

Assess the intake of carbohydrate quality and their association with cardiovascular risk factors among diabetes subtypes.

METHODS

Participants of the German Diabetes Study (GDS) (recent-onset diabetes (n = 487) and 5-years thereafter (n = 209)) were allocated into severe autoimmune diabetes (SAID, 35%), severe insulin-deficient diabetes (SIDD, 3%), severe insulin-resistant diabetes (SIRD, 5%), mild obesity-related diabetes (MOD, 28%), and mild age-related diabetes (MARD, 29%). Dietary glycemic index (GI), glycemic load (GL), and intake of higher- (≥ 55) and low-GI (< 55) foods, dietary fiber, and total sugar were derived from a validated food frequency questionnaire and cross-sectionally associated with cardiovascular risk factors (blood lipids, subclinical inflammation, blood pressure, fatty liver index) using multivariable linear regression analysis for subtypes with prevalences ≥ 10%.

RESULTS

Intake of carbohydrate quality parameters was broadly comparable between the subtypes. Among SAID higher total sugar intake was associated with lower HDL-cholesterol (ß (95% CI) relative change per 1 SD increment: - 3.4% (- 6.7; - 0.1)). No clear associations were seen among MOD. Among MARD, a higher dietary GL and higher-GI carbohydrate intake were associated with higher serum triglycerides (10.9% (2.4; 20.1), 12.4% (3.9; 21.5)) and fatty liver index (absolute change: 0.18 (0.06; 0.31), 0.17 (0.05; 0.28)) and lower HDL-cholesterol (- 4.1% (- 7.6; - 0.4), - 4.4% (- 7.8; - 0.8)), whilst higher intake of low-GI carbohydrates and dietary fiber were associated with lower high-sensitivity C-reactive protein (- 16.0% (- 25.7; - 5.1), - 13.9% (- 24.2; - 2.2)).

CONCLUSIONS

Associations of carbohydrate quality parameters with blood lipids, subclinical inflammation, and fatty liver index differed between diabetes subtypes. However, evidence is too preliminary to derive subtype-specific recommendations.

TRIAL REGISTRATION

Clinicaltrials.gov: NCT01055093.

Edible Mushrooms: a Nutrient-Rich Ingredient for Healthier Food Products - A Review

OBJECTIVE OF THE REVIEW

Edible mushrooms are found to be foods with high nutritional content, which have been shown to be more widely used ingredients in cooking in traditional dishes. This article explores the rising trend in the use of edible mushrooms in new formulations of functional foods, taking advantage of their properties and benefits in human health.

RECENT FINDINGS

The use of mushrooms as an ingredient in new or modified food formulations is driven by solid evidence of their nutritional content and bioactivity. Mushrooms stand out for their high biological value and high bioavailability protein content, as well as dietary fiber that promotes improved digestive health. Other micronutrients present are B vitamins and minerals such as selenium, phosphorus and potassium. Mushroom flour has been the prevalent mode of addition to food formulations. This type of format aims to preserve and concentrate the nutritional content of mushrooms and has achieved nutritional enrichment of products. The use of this food has also been explored to improve technological qualities in food development, so it is intended to position itself as a natural additive. This review synthesizes data on the nutritional composition, bioactive properties, and physicochemical attributes of mushrooms, emphasizing their multifaceted contributions to modern food formulations. It advocates for further research to optimize mushroom application in diverse food products and to address practical challenges for seamless integration.

Serum Lipidomic Signatures Mediate the Association Between Coarse Grain Preference and Central Obesity in Adults With Normal Weight and High Wheat Intake

Little is known about the association between grain preference andabdominal fat accumulation, and mediating roles of circulating lipidomicsignatures. We quantified 1245 circulating lipids in 150 normal-weight centralobesity (NWCO) cases and 150 controls using targeted lipidomics. Grainpreference was determined by the highest intake frequency of grains (whiterice, wheat, or coarse grain). In our participants with high wheat intakefrequency, preferring coarse grain over rice was associated with a 60% lowerrisk of NWCO. Of the 585 lipids showing opposing associations with white riceand coarse grains, 46 were significantly linked to either (p < 0.05), predominantly alkylacyl phospholipids (PE-Os; n < 9) and alkenylacylphospholipids (PE-Ps; nx = 7). Network analysis identified a module primarilycomposed of PE-Os and PE-Ps, which was positively associated with coarse grain (p = 0.014). Another module, mainly consisting of triacylglycerols (TGs), was associatedwith white rice (p = 0.003) and mediated the association between white rice(mediation proportion: 20.30%; p = 0.027) or coarse grain preference (11.43%; p = 0.040) and NWCO. Specific lipids, such as TG(8:0_16:0_16:0) and TG(8:0_14:0_18:0), exhibited notable mediation effects. In normal-weight individuals with highwheat intake frequency, preferring coarse grain was inversely associated with NWCO, mediated by specific lipidomic signatures.

Metabolic engineering-induced transcriptome reprogramming of lipid biosynthesis enhances oil composition in oat

The endeavour to elevate the nutritional value of oat (Avena sativa) by altering the oil composition and content positions it as an optimal crop for fostering human health and animal feed. However, optimization of oil traits on oat through conventional breeding is challenging due to its quantitative nature and complexity of the oat genome. We introduced two constructs containing three key genes integral to lipid biosynthesis and/or regulatory pathways from Arabidopsis (AtWRI1 and AtDGAT1) and Sesame (SiOLEOSIN) into the oat cultivar 'Park' to modify the fatty acid composition. Four homozygous transgenic lines were generated with a transformation frequency of 7%. The expression of these introduced genes initiated a comprehensive transcriptional reprogramming in oat grains and leaves. Notably, endogenous DGAT, WRI1 and OLEOSIN genes experienced upregulation, while genes associated with fatty acid biosynthesis, such as KASII, SACPD and FAD2, displayed antagonistic expression patterns between oat grains and leaves. Transcriptomic analyses highlighted significant differential gene expression, particularly enriched in lipid metabolism. Comparing the transgenic oat plants with the wild type, we observed a remarkable increase of up to 34% in oleic acid content in oat grains. Furthermore, there were marked improvements in the total oil content in oat leaves, as well as primary metabolites changes in both oat grains and leaves, while maintaining homeostasis in the transgenic oat plants. These findings underscore the effectiveness of genetic engineering in manipulating oat oil composition and content, offering promising implications for human consumption and animal feeding through oat crop improvement programmes.

Therapeutic applications of carbohydrate-based compounds: a sweet solution for medical advancement

Carbohydrates, one of the most abundant biomolecules found in nature, have been seen traditionally as a dietary component of foods. Recent findings, however, have unveiled their medicinal potential in the form of carbohydrates-derived drugs. Their remarkable structural diversity, high optical purity, bioavailability, low toxicity and the presence of multiple functional groups have positioned them as a valuable scaffold and an exciting frontier in contemporary therapeutics. At present, more than 170 carbohydrates-based therapeutics have been granted approval by varying regulatory agencies such as United States Food and Drug Administration (FDA), Japan Pharmaceuticals and Medical Devices Agency (PMDA), Chinese National Medical Products Administration (NMPA), and the European Medicines Agency (EMA). This article explores an overview of the fascinating potential and impact of carbohydrate-derived compounds as pharmacological agents and drug delivery vehicles.

A Scoping Review of the Causal Pathways and Biological Mechanisms Linking Nutrition Exposures and Health Outcomes

BACKGROUND/AIM

Building on the evidence for multifaceted effects of different nutrients, foods and dietary patterns is a new priority for nutrition science. This review aims to describe the causal pathways and biological mechanisms that elucidate the associations between different nutrition exposures (nutrients, foods and dietary patterns) and health outcomes.

METHODS

A scoping review was conducted in two stages: 1) review of nutrition science textbooks; and 2) a review of reviews of empirical literature using a systematic approach to elucidate causal pathways and biological mechanisms for nutrition exposures and health outcomes. Reviews were eligible for inclusion if they reported biological mechanistic pathways between exposures and outcomes of interest among free-living healthy adults and/or children. Causal pathways within and between the exposures and the outcomes were identified and summarised visually.

RESULTS

A total of seven core textbooks and 1,934 reviews of relevant empirical literature were included. The complexity of the causal pathways and the number of biological mechanisms progressively increases as the nutrition exposure changes from nutrients to foods to dietary patterns. The biological mechanisms demonstrate that associations with beneficial or adverse health outcomes are determined by the contrasting chemical composition and physical structure of the different types and forms of nutrition exposures, and that contextual factors (e.g., food processing) can influence these chemical and physical factors for food and dietary pattern exposures.

CONCLUSION

This review provides models that can guide future research, and has several implications for the generation and interpretation of the nutrition evidence, and its synthesis and translation to inform nutrition guidelines and policies.

Associations between temporal eating patterns and energy distribution patterns with gallstones: a cross-sectional study based on NHANES 2017-2018

BACKGROUND

Gallstones are strongly associated with eating occasion (EO) and energy distribution, but few studies have addressed this aspect. Therefore, we utilize the data from 2017 to 2018 National Health and Nutrition Examination Survey (NHANES) to explore the association between temporal eating patterns and energy distribution patterns with the incidence of gallstones.

METHODS

Our study comprised participants who completed the NHANES dietary intake interview and self-reported health questionnaire at age 20 or older. The self-report method for gallstones (have you ever been told by a doctor) was used. We use the latent class analysis (LCA) identified temporal eating patterns, and identified energy distribution patterns through latent profile analysis (LPA). The association between temporal eating patterns, energy distribution patterns, and gallstones was examined using logistic regression modeling.

RESULTS

The study included a total of 4,692 participants. LCA identified four temporal eating patterns labeled as "Conventional," "Early breakfast," "Later breakfast," and "Grazing." Compared to the "Conventional" pattern, the "Early breakfast" pattern (OR 0.809, 95%CI 0.808-0.811) was associated with a reduced risk of gallstones, while the "Later breakfast" (OR 1.435, 95%CI 1.432-1.438) and "Grazing" (OR 1.147, 95%CI 1.145-1.148) patterns were associated with an increased risk of gallstones. LPA identified four energy distribution patterns labeled as "Guideline," "High carbohydrates," "Carbs-fat balance," and "High fat." The "High carbohydrates" pattern (OR 1.329, 95%CI 1.326-1.331) was associated with an increased risk of gallstones compared to the "Guideline" pattern. The "Carbs-fat balance" pattern (OR 0.877, 95%CI 0.876-0.879) and the "High fat" pattern (OR 0.848, 95%CI 0.846-0.850) were significantly and negatively associated with the risk of gallstones.

CONCLUSIONS

To summarize, inappropriate timing of eating and energy sources are associated with gallstones. As a dietary prevention measure for gallstones, we suggest adhering to a regular eating routine and avoiding overly casual and frequent food consumption. If the main EO routine occurs in the morning, this time should not exceed 9:00 a.m. Additionally, reducing carbohydrate intake and maintaining a moderate level of fat intake is believed to contribute to a lower risk of gallstones.

Enhanced Labeling to Promote Consumption of Nutrient Dense Foods and Healthier Diets

Background/Objectives: Efforts are underway worldwide to design and deploy food labeling systems that provide consumers with the information needed to shift dietary patterns toward nutrient dense, healthier foods. Despite a compelling need for progress, worrisome public health trends persist that are rooted in the popularity of unhealthy, heavily processed foods. Methods: The nutrition and health-related content on the packaging of nine common foods sold in the US and Europe is analyzed and compared. The current scope of nutrient-specific messaging is characterized, including messages highlighting health-related benefits stemming from the mix and levels of mostly macronutrients in food products. Results: An average of 6.9 unique nutrition-related messages appear on the packaging of nine US food products, while EU food products contain an average of 5.0. Messaging around the ingredients in food products accounts for the largest share, e.g., "100% whole grain", "Vegan", and "No artificial preservatives". The macronutrients of fat, fiber, cholesterol, salt, sugar, and protein are the focus of most messaging around health benefits. The degree of food processing and essential vitamin, mineral, and phytochemical micronutrients receive little or no attention, despite their importance in positive health outcomes. Conclusions: Current nutrition-related labeling fails to inform consumers of the enormous differences in the contribution of food products in meeting nutritional needs. Existing metrics and rating systems do not effectively account for the critical relationship between nutrient density and caloric content. Existing metrics and systems do not reflect the impacts of processing on food nutritional quality in ways that provide consumers meaningful information. New concepts, metrics, and label elements are described that could promote healthier dietary patterns. Clear and mandatory nutrition labeling could begin shifting market share toward healthier options, and this could trigger and guide changes in manufactured food recipes that make brand-name products healthier, benefiting all consumers.

The development and testing of a single-arm feasibility and acceptability study of a whole foods diet intervention for adults with prediabetes and their offspring

BACKGROUND

Diet is considered a first-line treatment option for prediabetes, a condition that affects 96 million United States (U.S.) adults. Diet patterns that prioritize whole foods (e.g., Mediterranean) are currently recommended to treat prediabetes. However, no studies have tested whether a U.S.-style diet pattern that prioritizes whole foods can be used to treat prediabetes. The purpose of this study was to assess the feasibility and acceptability of a whole foods diet for adults with prediabetes and their offspring prior to conducting a larger clinical trial.

METHODS

A 2-week single-arm pre-post experimental controlled-feeding intervention of a 2020-2025 Dietary Guidelines for Americans adapted whole foods diet (e.g., primarily focused on foods that have undergone limited processing or refinement) was conducted in adults (25-59 years) with prediabetes and their biological offspring (6-17 years). Families received 2 weeks of menus and grocery delivery and weekly counseling by a registered dietitian. Families were invited to attend an optional focus group session. Feasibility was based on having a ≥ 50% family completion rate with ≥ 80% completion of study outcomes. Measures included adult-child anthropometrics (weight [kg], body mass index [BMI] including BMI% and Z-scores for offspring, waist circumference [cm]) and child diet quality estimated using the 2015 Healthy Eating Index (HEI) from a single random food record. Wilcoxon signed rank was used to compare differences between baseline and 2-week anthropometrics measures and offspring total HEI scores. Qualitative data were analyzed using thematic analysis to understand factors attributed to diet adherence and acceptability.

RESULTS

Eight families enrolled (n = 8 adults, n = 12 offspring), with 7 families completing the study (12% attrition) and completing 100% of study outcome measures. Adults experienced a median weight loss of - 1.0 kg from baseline to 2 weeks (79.5 kg to 78.5 kg). Offspring had a 24-point increase in total 2015 HEI scores (median difference 50 to 74). Focus group participants (n = 4 adults) reported being satisfied with the program and expressed a willingness to continue the diet despite identified barriers.

CONCLUSIONS

A whole foods diet that provides dietary support was found to be feasible and acceptable for families at risk for T2D. Future studies are needed to test the effects of the diet on prediabetes outcomes, diet quality, and diet adherence in adults and families.

TRIAL REGISTRATION

NCT05483972 at ClinicalTrials.gov. Registered July 25, 2022. https://clinicaltrials.gov/study/NCT05483972?cond=prediabetes&term=whole%20foods%20&rank=1.

The association between dietary carbohydrate intake and the risk of hyperlipidemia among reproductive-aged women in the US: A cross-sectional study

BACKGROUND

The association between dietary carbohydrate intake and hyperlipidemia remained incompletely understood. This study aimed to explore the association between dietary carbohydrate intake and the risk of hyperlipidemia among reproductive-aged women in the US.

METHODS

The study utilized data from the National Health and Nutrition Examination Survey (NHANES) conducted from 2005 to 2020. Dietary intake information was assessed via interviews using 24-hour dietary recall interviews, and hyperlipidemia diagnosis adhered to the National Cholesterol Education Program guidelines. Univariate and multivariate logistic regression analyses, along with restricted cubic splines (RCS) and stratified analyses, were conducted to investigate the association between dietary carbohydrate intake and the risk of hyperlipidemia.

RESULTS

A total of 6,791 women of reproductive age, with a mean age of 34.87 (±8.57) years, were included in the final analysis. In the multivariate logistic regression model adjusting for covariates, a higher percentage of energy from carbohydrate was positively correlated with the risk of hyperlipidemia (adjusted odds ratio (AOR): 1.014, 95% CI: 1.004-1.024). Analyzing the percentage of energy from carbohydrate as a categorical variable, compared to the lowest quartile, the third quartile (AOR: 1.263, 95% CI: 1.031-1.546) and the highest quartile (AOR: 1.411, 95% CI: 1.083-1.839) were associated with increased hyperlipidemia risk. Additionally, a linear relationship (P for nonlinearity = 0.088) existed between the percentage of energy from carbohydrate and the risk of hyperlipidemia, with an inflection point identified at 49.64.

CONCLUSIONS

This study found that elevated dietary carbohydrate intake was associated with an increased the risk of hyperlipidemia in reproductive-aged women. These findings implied that reproductive-aged women should pay closer attention to reducing their carbohydrate intake.

Excess dietary sugar and its impact on periodontal inflammation: a narrative review

INTRODUCTION

Sugar is omnipresent in the current food environment and sugar consumption has drastically risen over the past century. Extensive evidence highlights the negative health consequences of consuming excess dietary sugars, leading the World Health Organization (WHO) and the American Heart Association (AHA) to devise guidelines to restrict sugar intake. According to the WHO's Global Oral Health Status Report of 2022, oral diseases and severe periodontitis are a massive public health problem, and dietary sugars are a modifiable risk factor.

METHODS

We conducted a literature review using key databases to summarise the health effects of excessive sugar consumption and their potential role in periodontal inflammation.

RESULTS AND CONCLUSION

Available evidence suggests that excess dietary fructose and sucrose can cause low-grade systemic inflammation; and induce dysbiosis in both gut and the oral microbiota. Also, dietary sugar is potentially addictive and hypercaloric and its overconsumption can lead to obesity, metabolic syndrome, and other risk factors for periodontal inflammation. Hence, an unbalanced diet with excess dietary sugars holds the potential to initiate and aggravate periodontal inflammation. In the modern food environment that enables and facilitates a high-sugar diet, adopting a diverse diet and restricting sugar intake according to WHO and AHA guidelines seem beneficial to systemic and periodontal health. Since clinical evidence is limited, future research should study the effectiveness of dietary interventions that control sugar consumption in preventing and managing the global public health problem of periodontal inflammation.

Effect of Honey on Postprandial Hyperglycemia in Alloxan-Induced Diabetic Rats

The role of postprandial hyperglycemia (PPH) has been identified as a contributing factor in the development of diabetes mellitus and its associated complications. The objective of this study was to investigate the effect of honey on high glucose-induced PPH in alloxan-induced diabetic rats. Diabetes mellitus was induced in overnight-fasted rats by administering alloxan [150 mg/kg body weight (BW)]. The diabetic rats were administered either drinking water (1 ml/kg BW) or honey (1, 2 or 3 g/kg BW) via oral gavage. Each group consisted of six rats. Prior to the administration of either the drinking water or the honey, the baseline fasting blood glucose (BG) was measured and recorded as BG0. Subsequently, BG levels (BG60, BG120 and BG180) were assessed at 60, 120 and 180 minutes, respectively. The estimation of the BG parameters concentration was performed, including the area under the curve (AUC), the peak BG (PBG), the percentage change in BG. The AUC and PBG did not differ between the diabetic groups (regardless of administered agents) and the diabetic control group. Compared with baseline fasting blood glucose (BG0), the BG60 significantly (p < 0.05) increased in diabetic rats that received drinking water or honey (2 or 3 g/kg BW) but not in diabetic rats that received 1 g/kg BW of honey. The diabetic rats that received 1 g/kg BW of honey exhibited significantly (p < 0.05) lower percentage change in BG compared with the diabetic control rats. The study demonstrated that the administration of honey (regardless of dosage) did not exacerbate high glucose-induced PPH in diabetic rats. The study also indicated that a dose of 1 g/kg BW of honey was the most effective dose in suppressing PPH.

Macronutrient quality and its association with micronutrient adequacy in children

BACKGROUND & AIMS

The double burden of malnutrition compels us to reconsider macronutrients from a diet quality perspective. The Macronutrient Quality Index (MQI) has been designed to reflect overall macronutrient quality and is based on three sub-indexes: the carbohydrate quality index (CQI), the healthy plate protein quality index (HPPQI) and the fat quality index (FQI). Nutritional adequacy is an essential aspect of diet quality that should be captured by reliable dietary indexes.

METHODS

We analyzed the association between the Macronutrient Quality Index (MQI) and micronutrient adequacy. Participants were children aged 4 and 5 years, recruited in the SENDO cohort. Baseline information was collected through a self-administered online questionnaire, which included information on sociodemographic, dietary, and lifestyle variables. Dietary information was obtained using a 147-item validated semi-quantitative food frequency questionnaire. Participants were categorized into tertiles based on their MQI score. We evaluated the intake of 20 micronutrients and assessed the probability of micronutrient adequacy using the Estimated Average Requirement cut-off point.

RESULTS

Children in the highest tertile of MQI had 0.33-fold lower odds (95%CI 0.17-0.66) of having ≥3 inadequate micronutrient intakes than their peers in the lowest tertile, after adjusting for potential confounders. The adjusted proportions of children with inadequate intake of ≥3 micronutrients were 18%, 14% and 11% in the first, second, and third tertiles of MQI respectively. The MQI appears to be capable of capturing nutrient adequacy in children, although our results suggest that a modified MQI, with eggs and dairy products weighted positively, might be more adequate for the pediatric population.

Dietary carbohydrate quality index and incidence of obesity-related cancers in the "Seguimiento Universidad De Navarra" (SUN) prospective cohort

PURPOSE

The quality, rather than the quantity, of carbohydrate intake may play a major role in the etiology of obesity-related cancers (ORCs). We assessed the association between a previously defined carbohydrate quality index (CQI) and the risk of developing ORCs in the "Seguimiento Universidad de Navarra" (SUN) cohort.

METHODS

A total of 18,446 Spanish university graduates [mean age 38 years (SD 12 years), 61% women, mean BMI 23.5 kg/m2 (SD 3.5 kg/m2)], with no personal history of cancer, were followed-up. Baseline CQI was assessed summing quintiles of four previously defined criteria: high dietary fiber intake, low glycemic index (GI), high whole-grain: total-grain carbohydrates ratio and high solid carbohydrates: total carbohydrates ratio. Participants were classified into tertiles of their total CQI. Incident ORCs were confirmed by an oncologist using medical records and by querying the National Death Index blindly to dietary exposures.

RESULTS

During a median follow-up of 13.7 years, 269 incident cases of ORC were confirmed. A higher CQI was inversely associated with ORC incidence [multivariable-adjusted hazard ratio (HR) for the upper (T3) versus the lowest tertile (T1) of 0.68 (95% CI: 0.47-0.96), p for trend = 0.047]. Particularly, higher dietary fiber intake was inversely associated with ORC, HRT3 vs. T1=0.57 (95% CI 0.37-0.88 p for trend = 0.013).

CONCLUSION

In this prospective Mediterranean cohort, an inverse association between a better global quality of carbohydrate intake and the risk of ORCs was found. Strategies for cancer prevention should promote a higher quality of carbohydrate intake.

Overall glycaemic index and dietary glycaemic load and all-cause and cause-specific mortality in women from the Mexican Teachers' Cohort

Previous studies have found direct associations between glycaemic index (GI) and glycaemic load (GL) with chronic diseases. However, this evidence has not been consistent in relation to mortality, and most data regarding this association come from high-income and low-carbohydrate-intake populations. The aim of this study was to evaluate the association between the overall GI and dietary GL and all-cause mortality, CVD and breast cancer mortality in Mexico. Participants from the Mexican Teachers' Cohort (MTC) study in 2006-2008 were followed for a median of 10 years. Overall GI and dietary GL were calculated from a validated FFQ. Deaths were identified by the cross-linkage of MTC participants with two national mortality registries. Cox proportional hazard models were used to estimate the impact of GI and GL on mortality. We identified 1198 deaths. Comparing the lowest and highest quintile, dietary GI and GL appeared to be marginally associated with all-cause mortality; GI, 1·12 (95 % CI: 0·93, 1·35); GL, 1·12 (95 % CI: 0·87, 1·44). Higher GI and GL were associated with increased risk of CVD mortality, GI, 1·30 (95 % CI: 0·82, 2·08); GL, 1·64 (95 % CI: 0·87, 3·07) and with greater risk of breast cancer mortality; GI, 2·13 (95 % CI: 1·12, 4·06); GL, 2·43 (95 % CI: 0·90, 6·59). It is necessary to continue the improvement of carbohydrate quality indicators to better guide consumer choices and to lead the Mexican population to limit excessive intake of low-quality carbohydrate foods.

Energy Intake and Dietary Glycemic Load in Late Morning and Risk of Type 2 Diabetes: The Hispanic Community Health Study/Study of Latinos-A Multicenter Prospective Cohort Study

OBJECTIVE

To evaluate the association between meal timing and type 2 diabetes risk in U.S. Hispanic/Latino adults.

RESEARCH DESIGN AND METHODS

The Hispanic Community Health Study/Study of Latinos (HCHS/SOL) is a multicenter, community-based, prospective cohort study. This study included 8,868 HCHS/SOL adults without diabetes at baseline (2008-2011) and attending the visit 2 examination (2014-2017). Energy intake and glycemic load (GL) in each meal timing were assessed at baseline using two 24-h dietary recalls. Incident diabetes was identified through annual follow-up calls or at visit 2. Hazard ratios (HRs) for incident diabetes were estimated using Cox models, accounting for the complex survey design.

RESULTS

The study population (50.9% female) had a baseline mean age of 39.0 (95% CI, 38.4-39.5) years. Over a median (range) follow-up of 5.8 (0.8-9.6) years, 1,262 incident diabetes cases were documented. Greater energy intake and GL in late morning (9:00-11:59 a.m.) were associated with a lower diabetes risk, whereas greater energy intake and GL in other meal timings were not. After accounting for diet quantity and quality, sociodemographic characteristics, lifestyle factors, and chronic conditions, the HRs were 0.94 (95% CI, 0.91-0.97) per 100-kcal energy intake increment and 0.93 (0.89-0.97) per 10-unit GL increment in late morning. Replacing energy intake or GL from early morning (6:00-8:59 a.m.), afternoon (12:00-5:59 p.m.), or evening (6:00-11:59 p.m.) with late-morning equivalents was associated with a comparably lower diabetes risk.

CONCLUSIONS

This study identified late morning as a favorable meal timing in Hispanic/Latino adults, providing a novel perspective on type 2 diabetes prevention that warrants confirmation.

Nitrate: "the source makes the poison"

Interest in the role of dietary nitrate in human health and disease has grown exponentially in recent years. However, consensus is yet to be reached as to whether consuming nitrate from various food sources is beneficial or harmful to health. Global authorities continue to recommend an acceptable daily intake (ADI) of nitrate of 3.7 mg/kg-bw/day due to concerns over its carcinogenicity. This is despite evidence showing that nitrate consumption from vegetable sources, exceeding the ADI, is associated with decreased cancer prevalence and improvements in cardiovascular, oral, metabolic and neurocognitive health. This review examines the paradox between dietary nitrate and health and disease and highlights the key role of the dietary source and food matrix in moderating this interaction. We present mechanistic and epidemiological evidence to support the notion that consuming vegetable-derived nitrate promotes a beneficial increase in nitric oxide generation and limits toxic N-nitroso compound formation seen with high intakes of nitrate added during food processing or present in contaminated water. We demonstrate the need for a more pragmatic approach to nitrate-related nutritional research and guidelines. Ultimately, we provide an overview of our knowledge in this field to facilitate the various therapeutic applications of dietary nitrate, whilst maintaining population safety.

Association between quantity and quality of carbohydrate intake and glaucoma: a cross-sectional study from the NHANES database

BACKGROUND

Glaucoma is a public health problem among the worldwide population. Dietary as a modifiable factor have been reported to be associated with glaucoma. This study aimed to explore the association between quantity and quality of carbohydrate (CH) intake and glaucoma among U.S. adults.

METHODS

In this cross-sectional study, data of participants aged ≥ 40 years old were extracted from the National Health and Nutrition Examination Survey (NHANES) 2005-2008. CH intake information were obtained by 24-h dietary recall interview. Glaucoma was defined by regraded disc images. Covariates included demographic information, physical examination, laboratory values, complications and nutrients intake. The weighted univariable and multivariate logistic regression models were used to assess the association between the quantity and quality of CH intake and glaucoma. Subgroup analyses based on the history of hypertension were further assessed the association.

RESULTS

The weighted population included a total of 4789 participants, of whom 119 (2.48%) had glaucoma. After adjusting for age, adrenal cortical steroids, hypertension, chronic kidney diseases, diabetes and energy intake, high quantity (OR = 1.83, 95%CI: 1.08-3.11) and low quality (OR = 0.44, 95CI%: 0.20-0.98) of CH intake were associated with the higher odds of glaucoma. High quantity of CH intake (OR = 2.06, 95%CI: 1.15-3.69) was associated with the high odds of glaucoma in hypertension, while high quality of CH intake (fiber-to-CH ratio: OR = 0.23, 95%CI: 0.06-0.82; CH-to-fiber and fiber-to-added sugars ratio: OR = 0.10, 95%CI: 0.02-0.53) were associated with the lower odds of glaucoma in participants without hypertension.

CONCLUSION

In NAHNES 2005-2008, higher quantity and lower quality CH intake were associated with the high odds of glaucoma, especially among patients without hypertension. This study provides a theoretical basis for the health management of glaucoma patients from the perspective of dietary intake.

Current type 2 diabetes guidelines: Individualized treatment and how to make the most of metformin

Evidence-based guidelines provide the premise for the delivery of quality care to preserve health and prevent disabilities and premature death. The systematic gathering of observational, mechanistic and experimental data contributes to the hierarchy of evidence used to guide clinical practice. In the field of diabetes, metformin was discovered more than 100 years ago, and with 60 years of clinical use, it has stood the test of time regarding its value in the prevention and management of type 2 diabetes. Although some guidelines have challenged the role of metformin as the first-line glucose-lowering drug, it is important to point out that the cardiovascular-renal protective effects of sodium-glucose co-transporter-2 inhibitors and glucagon-like peptide-1 receptor agonists were gathered from patients with type 2 diabetes, the majority of whom were treated with metformin. Most national, regional and international guidelines recommend metformin as a foundation therapy with emphasis on avoidance of therapeutic inertia and early attainment of multiple treatment goals. Moreover, real-world evidence has confirmed the glucose-lowering and cardiovascular-renal benefits of metformin accompanied by an extremely low risk of lactic acidosis. In patients with type 2 diabetes and advanced chronic kidney disease (estimated glomerular filtration rate 15-30 mL/min/1.73m2), metformin discontinuation was associated with an increased risk of cardiovascular-renal events compared with metformin persistence. Meanwhile, it is understood that microbiota, nutrients and metformin can interact through the gut-brain-kidney axis to modulate homeostasis of bioactive molecules, systemic inflammation and energy metabolism. While these biological changes contribute to the multisystem effects of metformin, they may also explain the gastrointestinal side effects and vitamin B12 deficiency associated with metformin intolerance. By understanding the interactions between metformin, foods and microbiota, healthcare professionals are in a better position to optimize the use of metformin and mitigate potential side effects. The United Kingdom Prospective Diabetes Study and the Da Qing Diabetes Prevention Program commenced 40 years ago provided the first evidence that type 2 diabetes is preventable and treatable. To drive real-world impact from this evidence, payors, practitioners and planners need to co-design and implement an integrated, data-driven, metformin-based programme to detect people with undiagnosed diabetes and prediabetes (intermediate hyperglycaemia), notably impaired glucose tolerance, for early intervention. The systematic data collection will create real-world evidence to bring out the best of metformin and make healthcare sustainable, affordable and accessible.

Maternal Dietary Carbohydrate and Pregnancy Outcomes: Quality over Quantity

Dietary nutrition plays a crucial role in determining pregnancy outcomes, with poor diet being a major contributor to pregnancy metabolic syndrome and metabolic disorders in offspring. While carbohydrates are essential for fetal development, the excessive consumption of low-quality carbohydrates can increase the risk of pregnancy complications and have lasting negative effects on offspring development. Recent studies not only highlighted the link between carbohydrate intake during pregnancy, maternal health, and offspring well-being, but also suggested that the quality of carbohydrate foods consumed is more critical. This article reviews the impacts of low-carbohydrate and high-carbohydrate diets on pregnancy complications and offspring health, introduces the varied physiological effects of different types of carbohydrate consumption during pregnancy, and emphasizes the importance of both the quantity and quality of carbohydrates in nutritional interventions during pregnancy. These findings may offer valuable insights for guiding dietary interventions during pregnancy and shaping the future development of carbohydrate-rich foods.

Associations of diet with infectious diseases in UK Biobank

This research aims to utilize multivariate logistic regression to explore associations between the frequency of 13 food groups intake (or four diet groups) and infectious diseases. 487849 participants from the UK Biobank were enrolled, and 75209 participants were diagnosed with infectious diseases. Participants reporting the highest intake frequency of processed meat [odds ratio ( OR) = 1.0964; 95% CI: 1.0622-1.1318] and red meat ( OR = 1.0895; 95% CI: 1.0563-1.1239) had a higher risk of infectious diseases compared to those with the lowest intake frequency. Consuming fish 2.0-2.9 times ( OR = 0.8221; 95% CI: 0.7955-0.8496), cheese ≥5.0 times ( OR = 0.8822; 95% CI: 0.8559-0.9092), fruit 3.0-3.9 servings ( OR = 0.8867; 95% CI: 0.8661-0.9078), and vegetables 2.0-2.9 servings ( OR = 0.9372; 95% CI: 0.9189-0.9559) per week were associated with a lower risk of infection. Low meat-eaters ( OR = 0.9404; 95% CI: 0.9243-0.9567), fish-eaters ( OR = 0.8391; 95% CI: 0.7887-0.8919), and vegetarians ( OR = 0.9154; 95% CI: 0.8561-0.9778) had a lower risk of infectious diseases compared to regular meat-eaters. Mediation analysis was performed, revealing glycosylated hemoglobin, white blood cell counts, and body mass index were mediators in the relationships between diet groups and infectious diseases. This study suggested that intake frequency of food groups is a factor in infectious diseases and fish-eaters have a lower risk of infection.

Low-carbohydrate dietary score and the incidence of metabolically unhealthy phenotype based on BMI status: a cohort study

There is scarce research focusing on the relationship between the low-carbohydrate dietary score and the development of a metabolically unhealthy phenotype. Therefore, this cohort study was designed to assess the association between the low-carbohydrate dietary score and the risk of metabolically unhealthy phenotypes (MUP). This study included 1299 adults with healthy metabolic profiles who were followed for 5.9 years. Results indicated an inverse association between the second tertile of the low-carbohydrate dietary score and the risk of developing metabolically unhealthy obesity (MUO) (HR: 0.76, 95% CI: 0.59-0.98). In addition, we found an inverse association between the healthy low-carbohydrate dietary score and the risk of MUO (HR: 0.77, 95% CI: 0.60-0.99). Our results revealed a nonlinear inverse association between the low-carbohydrate dietary score and the risk of MUP only in subjects with overweight or obesity. This relationship was independent of animal protein and fat intake. Also, we found that a lower intake of unhealthy carbohydrates was associated with a lower risk of MUP only in subjects with overweight or obesity.

Pragmatic Carbohydrate Quality Metrics in Relation to Glycemic Index, Glycemic Load, and Front-of-Pack Warning Labels in Grain Foods

The challenges in the characterization of the nutritional quality of grain foods comprise obstacles to public health actions toward promotion of healthier grain-based foods. The present study investigated how carbohydrate metrics related to glycemic index (GI), glycemic load (GL), and warning labels of grain foods consumed by individuals living in São Paulo, Brazil. Information on intake of grain foods at individual level was obtained using 24 h recalls within a cross-sectional population-based survey conducted in 2015. There were 244 unique grain products reported by individuals in the survey, assessed through four metrics of carbohydrate quality, considering contents per 10 g of total carbohydrate: (1) ≥1 g fiber, (2) ≥1 g fiber and <1 g free sugars, (3) ≥1 g fiber and <2 g free sugars, and (4) ≥1 g fiber, and <2 g free sugars per 1 g of fiber. Outcomes included GI, GL, and inclusion of warning labels proposed by the Brazilian National Health Surveillance Agency (ANVISA), the Chilean Ministry of Health (1st and 3rd stages), and the Pan American Health Organization (PAHO). Metrics identified products with lower mean GI (-12.8 to -9.0 [p-values < 0.001]), and GL (-12.5 to -10.3 [p-values < 0.001]). Warning systems showed a certain degree of discrimination between products according to the metrics (p-value < 0.01 each); however, >50% of products with good nutritional quality according to the carbohydrate metrics still would receive warnings. Findings suggest that carbohydrate metrics identified products with lower GI and GL, and current warning labels may not adequately capture overall nutritional quality of grain foods.

Diet strategies for promoting healthy aging and longevity: An epidemiological perspective

In recent decades, global life expectancies have risen significantly, accompanied by a marked increase in chronic diseases and population aging. This narrative review aims to summarize recent findings on the dietary factors influencing chronic diseases and longevity, primarily from large cohort studies. First, maintaining a healthy weight throughout life is pivotal for healthy aging and longevity, mirroring the benefits of lifelong, moderate calorie restriction in today's obesogenic food environment. Second, the specific types or food sources of dietary fat, protein, and carbohydrates are more important in influencing chronic disease risk and mortality than their quantity. Third, some traditional diets (e.g., the Mediterranean, Nordic, and Okinawa) and contemporary dietary patterns, such as healthy plant-based diet index, the DASH (dietary approaches to stop hypertension) diet, and alternate healthy eating index, have been associated with lower mortality and healthy longevity. These patterns share many common components (e.g., a predominance of nutrient-rich plant foods; limited red and processed meats; culinary herbs and spices prevalent in global cuisines) while embracing distinct elements from different cultures. Fourth, combining a healthy diet with other lifestyle factors could extend disease-free life expectancies by 8-10 years. While adhering to core principles of healthy diets, it is crucial to adapt dietary recommendations to individual preferences and cultures as well as nutritional needs of aging populations. Public health strategies should aim to create a healthier food environment where nutritious options are readily accessible, especially in public institutions and care facilities for the elderly. Although further mechanistic studies and human trials are needed to better understand molecular effects of diet on aging, there is a pressing need to establish and maintain long-term cohorts studying diet and aging in culturally diverse populations.

Association between dietary carbohydrate to fiber ratio and metabolic dysfunction associated fatty liver disease in adults: evidence from the NHANES 2017-2020

This study aimed to explore the association of carbohydrate to fiber ratio (CFR) with metabolic dysfunction-associated fatty liver disease (MAFLD) in adults. In this study, data from the 2 cycles (2017-2018 and 2019-2020) of the NHANES were used. Univariate and multivariate weighted logistic regression analyses were applied to evaluate the association between CFR and MAFLD. Odds ratios (ORs) and 95% confidence levels (CIs) were estimated. Subgroup analysis was further performed in terms of gender, age and comorbidity (diabetes, hypertension). A total of 3180 individuals were included, with 1408 (44.28%) in the non-MAFLD group and 1772 (55.72%) in the MAFLD group. After adjusting different variables, a dietary fiber intake of 11.15-18.40 g was associated with significantly lower odds of MAFLD compared with a fiber intake < 11.15 g (OR = 0.71, 95% CI 0.54-0.93). In contrast to a dietary CFR < 12.58, a CFR > 19.91 was associated with significantly higher odds of MAFLD (OR = 1.57, 95% CI 1.09-2.27). Compared with females with a dietary CFR < 12.58, those with a CFR > 19.91 had significantly increased odds of MAFLD (OR = 1.87, 95% CI 1.29-2.73). Among individuals aged < 65 years, a dietary CFR > 19.91 was associated with higher odds of MAFLD than a dietary CFR < 12.58 (OR = 1.52, 95% CI 1.02-2.25). For participants without diabetes (OR = 1.79, 95% CI 1.26-2.54) or hypertension (OR = 1.93, 95% CI 1.02-3.65), a dietary CFR > 19.91 was associated with elevated odds of MAFLD than a CFR < 12.58. In summary, a higher CFR was associated with significantly greater odds of MAFLD, indicating the negative association between carbohydrate quality and MAFLD. The research would be conducive to metabolic dysfunction-associated fatty liver disease treatment.

Low-Glycemic Load Diets and Thyroid Function: A Narrative Review and Future Perspectives

Nutrition and calorie intake are associated with subtle changes of thyroid function tests in subjects with an intact Hypothalamic-Pituitary-Thyroid axis. Iodine deficiency and extreme fluctuations in calorie intake, such as those that occur during periods of starvation or overfeeding could lead to alterations in thyroid hormones. The dietary macronutrient and micronutrient composition could also influence the thyroid function. Recently, Low-Glycemic Load (LGL) diets have become very popular and are effective in the treatment and/or prevention of several medical conditions, including diabetes, obesity, cardiovascular disease, and epilepsy. In this review, we report on the available data from the literature regarding the association between LGL diets and thyroid function or dysfunction. Several studies conducted in this field to date have yielded inconsistent results.

The association between plant-based diet indices and metabolic syndrome: a systematic review and dose-response meta-analysis

Aim/introduction

The prevalence of metabolic syndrome (MetS) and its components have markedly increased worldwide. Among lifestyle factors introduced to lower the risk of MetS, healthy dietary patterns have gained considerable attention. This study aimed to assess the association between adherence to plant-based diet indices including O-PDI (overall plant-based diet index), H-PDI (healthy plant-based diet index), U-PDI (unhealthy plant-based diet index), and risk of MetS development.

Methods

To find related observational studies which assessed the association between Plant-based Diet indices and risk of MetS development, PubMed/Medline, Scopus, and Web of Science databases were searched from January 2016 to November 2023. A random effects model was used to estimate pooled odds ratios (OR) and 95% confidence intervals (95% CI). To assess the heterogeneity of included studies, the I2 index was used.

Results

Nine studies including 34,953 participants from the initial 288 studies were recognized to include in this meta-analysis study. According to pooled analysis, there was a significant relationship between the adherence to H-PDI and the lower risk of MetS (ES: 0.81; 95% CI: 0.67, 0.97; I2 = 77.2%, p < 0.001), while greater adherence to U-PDI was associated with 27% increases in the risk of MetS (ES: 1.27; 95% CI: 1.05, 1.54; I2 = 76.8%, p < 0.001). According to our analysis of the association between adherence to PDIs and the risk of MetS components, greater adherence to O-PDI and H-PDI was significantly associated with a higher risk of elevated FBS and obesity, respectively. As well, greater adherence to U-PDI was significantly associated with a higher risk of obesity, hypertriglyceridemia, low HDL-C, and elevated FBS.

Conclusion

Our results highlighted the importance of food choices in the context of a plant-based dietary pattern, indicating that adherence to unhealthy plant-based dietary patterns rich in less healthful carbohydrates may induce the risk of MetS development.

Systematic review registration

PROSPERO CRD42023428981.

The Vicious Cycle of Type 2 Diabetes Mellitus and Skeletal Muscle Atrophy: Clinical, Biochemical, and Nutritional Bases

Today, type 2 diabetes mellitus (T2DM) and skeletal muscle atrophy (SMA) have become increasingly common occurrences. Whether the onset of T2DM increases the risk of SMA or vice versa has long been under investigation. Both conditions are associated with negative changes in skeletal muscle health, which can, in turn, lead to impaired physical function, a lowered quality of life, and an increased risk of mortality. Poor nutrition can exacerbate both T2DM and SMA. T2DM and SMA are linked by a vicious cycle of events that reinforce and worsen each other. Muscle insulin resistance appears to be the pathophysiological link between T2DM and SMA. To explore this association, our review (i) compiles evidence on the clinical association between T2DM and SMA, (ii) reviews mechanisms underlying biochemical changes in the muscles of people with or at risk of T2DM and SMA, and (iii) examines how nutritional therapy and increased physical activity as muscle-targeted treatments benefit this population. Based on the evidence, we conclude that effective treatment of patients with T2DM-SMA depends on the restoration and maintenance of muscle mass. We thus propose that regular intake of key functional nutrients, along with guidance for physical activity, can help maintain euglycemia and improve muscle status in all patients with T2DM and SMA.

Fortification of dough with moringa, coriander, and amaranth improves the nutritional composition, health-benefiting properties, and sensory attributes of Nigerian wheat bread

Consumption of bread can be associated with some health issues, which can be improved by fortifying it with plants that are good sources of nutrients and bioactive compounds. This study investigated the effects of fortifying bread with 3 leafy vegetables on the quality of Nigerian wheat bread. Leave powders of coriander, moringa, and amaranths were added to wheat dough at 0% (control), 1%, 3%, 5%, or 7%, and the blends obtained were used to bake vegetable breads, which were then analyzed for proximate, minerals, total phenolics, antioxidant activity, reducing sugars, glycemic index, and sensory evaluation. Results showed that vegetable fortification significantly increased bread ash (from 0.84% in control up to 1.93% in fortified bread), crude fiber (from 1.68% to 3.29%), and nutritionally important minerals Ca, Mg, P, Fe, and Zn (up to 5.2-fold, 5.1-fold, 18.1-fold, 4.1-fold, and 14.0-fold, respectively); it reduced carbohydrates (from 65.65% down to 43.16%), crude lipids (from 2.25% down to 0.44%), and caloric value (from 1239.65 down to 1125.19 kJ/100 g), with little or no effect on proteins and moisture content. The fortification also improved the bioactive properties of the bread, as evidenced by a considerably higher phenolic content (from 0.40 up to 13.95 mg/100 g GAE) and increased antioxidant activities. There was a significant 1.1-to 3.4-fold decrease in the reducing sugars of composite breads with 5% and 7% vegetable powder, and the selected bread formulation with Moringa 7% lowered the glycemic index of rats by 3.5-fold. Fortification did not generally affect the appearance and taste of the breads but decreased other sensory parameters and overall acceptability; the bread sample enriched with 1% amaranth received the highest general acceptance. In conclusion, fortifying wheat bread with the 3 vegetables improves its nutritional quality and can be recommended as a new pathway for the development of more nutritious and healthy bread.

Therapeutic Applications of Plant and Nutraceutical-Based Compounds for the Management of Type 2 Diabetes Mellitus: A Narrative Review

Diabetes mellitus is a condition caused by a deficiency in insulin production or sensitivity that is defined by persistent hyperglycemia as well as disturbances in glucose, lipid, and protein metabolism. Uncurbed diabetes or incessant hyperglycemic condition can lead to severe complications, including renal damage, visual impairment, cardiovascular disease, neuropathy, etc., which promotes diabetes-associated morbidity and mortality rates. The therapeutic management of diabetes includes conventional medications and nutraceuticals as complementary therapies. Nutraceuticals are bioactive compounds derived from food sources that have health-promoting properties and are instrumental in the management and treatment of various maladies. Nutraceuticals are clinically exploited to tackle DM pathogenesis, and the clinical evidence suggests that nutraceuticals can modulate biochemical parameters related to diabetes pathogenesis and comorbidities. Hypoglycemic medicines are designed to mitigate DM in traditional medicinal practice. This review intends to emphasize and comment on the various therapeutic strategies available to manage this chronic condition, conventional drugs, and the potential role of nutraceuticals in managing the complexity of the disease and reducing the risk of complications. In contrast to conventional antihyperglycemic drugs, nutraceutical supplements offer a higher efficacy and lesser adverse effects. To substantiate the efficacy and safety of various functional foods in conjunction with conventional hypoglycemic medicines, additional data from clinical studies are required.

Unravelling marker trait associations linking nutritional value with pigmentation in rice seed

While considerable breeding effort has focused on increasing the yields of staple crops such as rice and the levels of micronutrients such as iron and zinc, breeding to address the problems of the double-burden of malnutrition has received less attention. Pigmented rice has higher nutritional value and greater health benefits compared to white rice. However, the genetic associations underlying pericarp coloration and accumulation of nutritionally valuable compounds is still poorly understood. Here we report the targeted genetic analysis of 364 rice accessions, assessing the genetic relationship between pericarp coloration (measured using multi-spectral imaging) and a range of phenolic compounds with potential nutritional and health-promoting characteristics. A genome-wide association study resulted in the identification of over 280 single nucleotide polymorphisms (SNPs) associated with the traits of interest. Many of the SNPs were associated with more than one trait, colocalization occurring between nutritional traits, and nutritional and color-related traits. Targeted association analysis identified 67 SNPs, located within 52 candidate genes and associated with 24 traits. Six haplotypes identified within the genes Rc/bHLH17 and OsIPT5 indicated that these genes have an important role in the regulation of a wide range of phenolic compounds, and not only those directly conferring pericarp color. These identified genetic linkages between nutritionally valuable phenolic compounds and pericarp color present not only a valuable resource for the enhancement of the nutritional value of rice but an easy method of selection of suitable genotypes.

Association between longitudinal dietary patterns and changes in obesity: a population-based cohort study

Introduction

Research on the trajectory of dietary patterns and changes in obesity has been inconclusive.

Methods

This study described the dietary intake and adiposity trajectories of Chinese adults and assessed the association between dietary trajectories and changes in body mass index (BMI) and waist-to-hip ratio (WHR). We used data from 3, 643 adults who participated in the China Health and Nutrition Survey from 1997 to 2015. Detailed dietary data were collected by conducting three consecutive 24-h recalls. Multitrajectories of diet scores were identified by a group-based multitrajectory method. We described the change in BMI and WHR using group-based trajectory modeling. We assessed the associations between dietary trajectories and changes in people with obesity using a logistic regression model.

Results

Our study revealed four trajectories of low-carbohydrate (LCD) and low-fat diet (LFD) scores. Three adiposity trajectories were identified according to the baseline level and developmental trend of BMI and WHR. Compared with the reference group, which was characterized by sustained healthy dietary habits with healthy diet scores at baseline and sustained maintenance of healthy diet scores, the other three diet trajectories had a higher risk of falling into the adverse adiposity trajectory.

Discussion

Maintaining a healthy LCD and LFD can markedly decrease the risk of adiposity.

The Potential Role of Nutrition in Overtraining Syndrome: A Narrative Review

Competition between athletes and an increase in sporting knowledge have greatly influenced training methods while increasing the number of them more and more. As a result, the number of athletes who have increased the number and intensity of their workouts while decreasing recovery times is rising. Positive overtraining could be considered a natural and fundamental process when the result is adaptation and improved performance; however, in the absence of adequate recovery, negative overtraining could occur, causing fatigue, maladaptation, and inertia. One of the earliest forms of fatigue is overreaching. It is considered to be an accumulation of training that leads to reduced sports performance, requiring days or weeks to recover. Overreaching, if followed by adequate recovery, can lead to an increase in athletic performance. Nonetheless, if overreaching becomes extreme, combined with additional stressors, it could lead to overtraining syndrome (OTS). OTS, caused by systemic inflammation, leads to central nervous system (CNS) effects, including depressed mood, further inflammation, central fatigue, and ultimately neurohormonal changes. There are therefore not only physiological, biochemical, and immunological but also psychological symptoms or markers that must be considered, independently or together, being intrinsically linked with overtraining, to fully understand OTS. However, to date, there are very few published studies that have analyzed how nutrition in its specific food aspects, if compromised during OTS, can be both etiology and consequence of the syndrome. To date, OTS has not yet been fully studied, and the topic needs further research. The purpose of this narrative review is therefore to study how a correct diet and nutrition can influence OTS in all its aspects, from prevention to treatment.

Low-Carbohydrate and Low-Fat Diet with Metabolic-Dysfunction-Associated Fatty Liver Disease

BACKGROUND

This observational cross-sectional study was designed to explore the effects of a low-carbohydrate diet (LCD) and a low-fat diet (LFD) on metabolic-dysfunction-associated fatty liver disease (MAFLD).

METHODS

This study involved 3961 adults. The associations between LCD/LFD scores and MAFLD were evaluated utilizing a multivariable logistic regression model. Additionally, a leave-one-out model was applied to assess the effect of isocaloric substitution of specific macronutrients.

RESULTS

Participants within the highest tertile of healthy LCD scores (0.63; 95% confidence interval [CI], 0.45-0.89) or with a healthy LFD score (0.64; 95%CI, 0.48-0.86) faced a lower MAFLD risk. Furthermore, compared with tertile 1, individuals with unhealthy LFD scores in terile 2 or tertile 3 had 49% (95%CI, 1.17-1.90) and 77% (95%CI, 1.19-2.63) higher risk levels for MAFLD, respectively.

CONCLUSIONS

Healthy LCD and healthy LFD are protective against MAFLD, while unhealthy LFD can increase the risk of MAFLD. Both the quantity and quality of macronutrients might have significant influences on MAFLD.

Association of carbohydrate intake from different sources with all-cause and cardiovascular mortality among chronic kidney disease populations: assessment of 1999-2018 National Health and Nutrition Examination Survey participation

This study analysed the data from the NHANES (1999-2018) to examine how different sources of carbohydrate intake affected the all-cause and cardiovascular mortality of 11,302 chronic kidney disease (CKD) patients. The data were adjusted for other factors using various methods. The results showed that CKD patients (stages 1-2 and 3-5) who consumed more carbohydrates from whole grains, fruits, vegetables and less carbohydrates from fruit juice or sauces had lower mortality rates. Replacing fat intake with carbohydrates from whole grains (HR = 0.86[0.78-0.95]), fruits (raw) (HR = 0.79[0.70-0.88]) and non-starchy vegetables (HR = 0.82[0.70-0.96]), but not protein intake, was linked to lower all-cause mortality. The fibre content in carbohydrates might partly account for the benefits of selected carbohydrate intake. This study provided practical recommendations for optimising the carbohydrate sources in CKD patients.

Determination of glycaemic response to the consumption of two specialised formulas for glycaemic control

To assess the glycaemic response after ingestion of two specialised oral and enteral nutrition formulas for glycaemic control. The participants were sixteen healthy volunteers, aged 21-49 years, with normal glucose tolerance. The volunteers attended the tests fasting for 10 h, for 5 weeks, and consumed the reference food - glucose solution - for 3 weeks, and the two formulas DiamaxO and DiamaxIG in the following weeks, in amounts equivalent to 25 g of available carbohydrates. During the period of 120 min, seven blood samples were taken through capillary blood sampling to determine the glycaemic response. The glycaemic index (GI) was calculated according to the trapezoidal rule, ignoring areas below the fasting line. The glycaemic load (GL) was determined by the formula GL = ((GI(glucose = reference) × 'g' of available carbohydrate per serving]/100. The formulas showed low GI and GL. GI = 37·8 and GL = 6·6 for DiamaxO and GI = 21·5 and GL = 3·5 for DiamaxIG. The peak of the glycaemic response occurred 30 min after ingestion, with a marked difference in blood glucose between the Diamax products in relation to glucose. Differences were also significant at times 15, 45, 60 and 90 min in relation to glucose (ANOVA with post hoc Bonferroni, P < 0·005), but not between the two products. However, the AUC and the GI of DiamaxIG are significantly smaller than that of the DiamaxO second t test (P = 0·0059). The glycaemic response to the products is quite reduced, presenting a curve with a little accentuated shape, without high peak, especially in the modified product.

Infrared and vibrational circular dichroism spectra of methyl β-D-glucopyranose in water: The application of the quantum cluster growth and clusters-in-a-liquid solvation models

The infrared (IR) and vibrational circular dichroism (VCD) spectra of methyl β-D-glucopyranose in water were measured. Both implicit and explicit solvation models were utilized to explain the observed spectra. The vast body of existing experimental and theoretical data suggested that about eight explicit water molecules are needed to account for the solvent effects, supported by the current Quantum Cluster Growth (QCG) analysis. Extensive manual and systematic conformational searches of the molecular target and its water clusters were carried out by using a recently developed conformational searching tool, conformer-rotamer ensemble sampling tool (CREST), and the microsolvation model in the associated QCG code. The Boltzmann averaged IR and VCD spectra of the methyl β-D-glucopyranose-(water)n (n = 8) conformers in the PCM of water provide better agreement with the experimental ones than those with n = 0, 1, and 2. The explicit solvation with eight water molecules was shown to greatly modify the conformational preference of methyl β-D-glucopyranose from its monomeric form. Further analyses show that the result is consistent with the existence of long-lived methyl β-D-glucopyranose monohydrates with the additional explicit water effects being accounted for with the quantum mechanical treatment of the other seven close-by water molecules in the PCM of water.

Association between changes in carbohydrate intake and long term weight changes: prospective cohort study

OBJECTIVE

To comprehensively examine the associations between changes in carbohydrate intake and weight change at four year intervals.

DESIGN

Prospective cohort study.

SETTING

Nurses' Health Study (1986-2010), Nurses' Health Study II (1991-2015), and Health Professionals Follow-Up Study (1986-2014).

PARTICIPANTS

136 432 men and women aged 65 years or younger and free of diabetes, cancer, cardiovascular disease, respiratory disease, neurodegenerative disorders, gastric conditions, chronic kidney disease, and systemic lupus erythematosus before baseline.

MAIN OUTCOME MEASURE

Weight change within a four year period.

RESULTS

The final analyses included 46 722 women in the Nurses' Health Study, 67 186 women in the Nurses' Health Study II, and 22 524 men in the Health Professionals Follow-up Study. On average, participants gained 1.5 kg (5th to 95th centile -6.8 to 10.0) every four years, amounting to 8.8 kg on average over 24 years. Among men and women, increases in glycemic index and glycemic load were positively associated with weight gain. For example, a 100 g/day increase in starch or added sugar was associated with 1.5 kg and 0.9 kg greater weight gain over four years, respectively, whereas a 10 g/day increase in fiber was associated with 0.8 kg less weight gain. Increased carbohydrate intake from whole grains (0.4 kg less weight gain per 100 g/day increase), fruit (1.6 kg less weight gain per 100 g/day increase), and non-starchy vegetables (3.0 kg less weight gain per 100 g/day increase) was inversely associated with weight gain, whereas increased intake from refined grains (0.8 kg more weight gain per 100 g/day increase) and starchy vegetables (peas, corn, and potatoes) (2.6 kg more weight gain per 100 g/day increase) was positively associated with weight gain. In substitution analyses, replacing refined grains, starchy vegetables, and sugar sweetened beverages with equal servings of whole grains, fruit, and non-starchy vegetables was associated with less weight gain. The magnitude of these associations was stronger among participants with overweight or obesity compared with those with normal weight (P<0.001 for interaction). Most of these associations were also stronger among women.

CONCLUSIONS

The findings of this study highlight the potential importance of carbohydrate quality and source for long term weight management, especially for people with excessive body weight. Limiting added sugar, sugar sweetened beverages, refined grains, and starchy vegetables in favor of whole grains, fruit, and non-starchy vegetables may support efforts to control weight.

Effect of weight change on the association between overall and source of carbohydrate intake and risk of metabolic syndrome: Tehran lipid and glucose study

BACKGROUND

In this prospective cohort study, we aimed to evaluate the association between dietary carbohydrates, whole grains, refined grains, and simple sugar with the risk of metabolic syndrome (MetS) and assess the effect of weight change on these associations.

METHODS

This study was conducted within the framework of the Tehran Lipid and Glucose Study (TLGS). We included 1915 healthy participants with complete demographic, anthropometric and dietary measurements, among whom 591 developed MetS during 8.9 years of follow-up. Intake of dietary carbohydrates, whole grains, refined grains, and simple sugar was assessed with a validated semi-quantitative food frequency questionnaire. Multivariable adjusted Cox regression was used to estimate hazard ratios (HRs) for MetS events across tertiles of dietary variables. Using joint classification, the effect of weight change on the association between dietary variables and risk of MetS was assessed by Cox regression.

RESULTS

Carbohydrate intake was not associated with the risk of MetS in multivariable-adjusted models. Whole grains intake was inversely associated with the risk of MetS (HR: 0.78, CI: 0.63-0.98), while this association disappeared after adjustment for weight change. The risk of MetS increased by 11% (1.11, 1.09-1.14) for each 3% energy increment from simple sugar, and by 5% (1.05, 1.03-1.08) for each 1 serving/day increment in refined grains. Consumption of refined grains increased the risk of MetS; an effect modification of this association was found by weight change. Among subjects with weight loss, intake of refined grains < median intake decreased the risk of MetS (0.59, 0.41-0.87). However, consumption of refined grains ≥ median intake increased the risk of MetS in individuals with weight gain (1.47, 1.08-2.01). Simple sugar was positively associated with an increased risk of MetS, after adjustment for weight change (3.00, 2.37-3.82). In joint classification, intake of simple sugar greater than median intake increased the risk of MetS, independent of weight change.

CONCLUSION

Our findings suggest an effect modification by weight change on the association between carbohydrates, and refined grains intake and the risk of MetS. Weight loss along with lower consumption of carbohydrates, and refined grains reduced the risk of MetS. However, simple sugar intake, regardless of weight change, was associated with an increased risk of MetS.

Diet and Glycemic Index in Children with Type 1 Diabetes

In children with type 1 diabetes, a healthy lifestyle is important to control postprandial glycemia and to avoid hyperglycemic peaks that worsen the inflammatory state of vessels and tissues. Glycemic index and glycemic load are two important indexes which assess the quality and quantity of foods consumed during meals. The main macronutrients of the diet have a different effect on postprandial blood glucose levels, so it is important that diabetic children consume foods which determine a slower and steadier glycemic peak. In this review, we present the results of the most recent studies carried out in the pediatric population with T1D, whose aim was to analyze the effects of low-glycemic-index foods on glycemic control. The results are promising and demonstrate that diets promoting low-glycemic-index foods guarantee a greater glycemic stability with a reduction in postprandial hyperglycemic peaks. However, one of the main limitations is represented by the poor adherence of children to a healthy diet. In order to obtain satisfactory results, a possibility might be to ensure a balanced intake of low-, moderate- and high-glycemic-index foods, preferring those with a low glycemic index and limiting the consumption of the high- and moderate-glycemic-index types.

Association of meal timing of energy, macronutrients and foods with hypercholesterolaemia in the US adults

Few studies examined the association of energy, macronutrients and food consumption at dinner v. breakfast with hypercholesterolaemia. A total of 27 911 participants from the National Health and Nutrition Examination Survey (2003-2016) were included in the cross-sectional study. Energy, macronutrients and food consumption at breakfast, dinner and the difference at dinner v. breakfast (Δratio) were calculated. Multiple logistic regression models and substitution effects of foods at dinner with breakfast were also performed. After adjustment for potential covariates, compared with the lowest quintile, participants in the highest quintile of Δratio in terms of energy had a higher risk of prevalent hypercholesterolaemia (ORΔratio of energy 1·16, 95 % CI (1·01, 1·33)) mainly due to Δratio of low-quality carbohydrates and plant protein (ORΔratio of low-quality carbohydrates 1·19; 95 % CI (1·05, 1·35)); ORΔratio of plant protein 1·13; 95 % CI (1·01, 1·28)). ΔAdded sugars and Δnuts were associated with hypercholesterolaemia (ORΔadded sugars 1·01; 95 % CI (1·00, 1·02)); ORΔnuts 1·08; 95 % CI (1·01, 1·16)). Furthermore, the substitution of added sugars, nuts and processed meat at dinner with breakfast could reduce the OR of hypercholesterolaemia. This study indicated that among US adults, overconsumption of energy, macronutrients including low-quality carbohydrates and plant protein at dinner than breakfast was significantly associated with a higher risk of prevalent hypercholesterolaemia. The replacing of added sugar, nuts and processed meat at dinner with breakfast reduced the risk of prevalent hypercholesterolaemia. This study emphasised the importance of meal timing in the prevention of hypercholesterolaemia.

A Hitchhiker's Guide to Problem Selection in Carbohydrate Synthesis

Oligosaccharides are ubiquitous in molecular biology and are used for functions ranging from governing protein folding to intercellular communication. Perhaps paradoxically, the exact role of the glycan in most of these settings is not well understood. One reason for this contradiction concerns the fact that carbohydrates often appear in heterogeneous form in nature. These mixtures complicate the isolation of pure material and characterization of structure-activity relationships. As a result, a major bottleneck in glycoscience research is the synthesis and modification of pure materials. While synthetic and chemoenzymatic methods have enabled access to homogeneous tool compounds, a central problem, particularly for newer synthetic chemists, is the matter of problem selection. This outlook aims to provide an entry level overview of fundamental principles in carbohydrate chemistry with an eye toward enabling solutions to frontier challenges.

Determining the metabolic effects of dietary fat, sugars and fat-sugar interaction using nutritional geometry in a dietary challenge study with male mice

The metabolic effects of sugars and fat lie at the heart of the "carbohydrate vs fat" debate on the global obesity epidemic. Here, we use nutritional geometry to systematically investigate the interaction between dietary fat and the major monosaccharides, fructose and glucose, and their impact on body composition and metabolic health. Male mice (n = 245) are maintained on one of 18 isocaloric diets for 18-19 weeks and their metabolic status is assessed through in vivo procedures and by in vitro assays involving harvested tissue samples. We find that in the setting of low and medium dietary fat content, a 50:50 mixture of fructose and glucose (similar to high-fructose corn syrup) is more obesogenic and metabolically adverse than when either monosaccharide is consumed alone. With increasing dietary fat content, the effects of dietary sugar composition on metabolic status become less pronounced. Moreover, higher fat intake is more harmful for glucose tolerance and insulin sensitivity irrespective of the sugar mix consumed. The type of fat consumed (soy oil vs lard) does not modify these outcomes. Our work shows that both dietary fat and sugars can lead to adverse metabolic outcomes, depending on the dietary context. This study shows how the principles of the two seemingly conflicting models of obesity (the "energy balance model" and the "carbohydrate insulin model") can be valid, and it will help in progressing towards a unified model of obesity. The main limitations of this study include the use of male mice of a single strain, and not testing the metabolic effects of fructose intake via sugary drinks, which are strongly linked to human obesity.

Associations between Low-Carbohydrate Diets and Low-Fat Diets with Frailty in Community-Dwelling Aging Chinese Adults

Frailty is a major health issue associated with aging. Diet affects frailty status; however, studies on the associations between the low-carbohydrate diet (LCD) score, low-fat diet (LFD) score and frailty in older Chinese adults are scarce. This study aimed to examine the associations between the LCD score, LFD score and risk of frailty in older Chinese adults. We analyzed data from 6414 participants aged ≥ 60 years from the China Northwest Natural Population Cohort: Ningxia Project. Frailty was measured using the frailty index (FI), calculated from 28 items comprising diseases, behavioral disorders and blood biochemistry and classified as robust, pre-frail and frail. LCD and LFD scores were calculated using a validated food frequency questionnaire (FFQ). Multiple logistic regression models were used to evaluate associations between LCD, LFD scores and frail or pre-frail status after adjusting for confounders. Participants' mean age was 66.60 ± 4.15 years, and 47.8% were male. After adjusting for age, sex, educational level, drinking, smoking, BMI, physical activity and total energy, compared to the lowest quartile (Q1: reference), the odds ratios (ORs) for pre-frail and frail status in the highest quartile (Q4) of LCD score were 0.73 (95% confidence intervals: 0.61-0.88; p for trend = 0.017) and 0.73 (95%CI: 0.55-0.95; p for trend = 0.035), respectively. No significant associations were observed between LFD score and either pre-frail or frail status. Our data support that lower-carbohydrate diets were associated with lower pre-frail or frail status, particularly in females, while diets lower in fat were not significantly associated with the risk of either pre-frail or frail status in older Chinese adults. Further intervention studies are needed to confirm these results.