Fruit and vegetable intake and risk of incident of type 2 diabetes: results from the consortium on health and ageing network of cohorts in Europe and the United States (CHANCES)

The Interactive Effects of Fruit Intake Frequency and Serum miR-484 Levels as Biomarkers for Incident Type 2 Diabetes in a Prospective Cohort of the Spanish Adult Population: The Di@bet.es Study

Background/Objectives: Although evidence suggests that miR-484 and several fruit components are involved in glucose metabolism and insulin resistance metabolic pathways, the relationship between serum miR-484 levels and fruit consumption in relation to the risk of Type 2 diabetes (T2DM) remains elusive. The aim of this study was to evaluate the possible association between serum miR-484 levels and fruit intake frequency with the risk of T2DM in the Spanish adult population. Methods: 2234 subjects from the Di@bet.es cohort study without T2DM at baseline were studied. Socio-demographic, anthropometric and clinical data were recorded, as well as responses to a questionnaire on habits, including frequency of fruit consumption (daily vs. occasional). T2DM was diagnosed at baseline and after 7.5 years of follow-up. Baseline serum miR-484 levels were measured using real-time qPCR and categorized based on the 25th percentile. Association analyses were performed using logistic regression models adjusted for potential confounders. Interaction effects were evaluated on the multiplicative and additive scales. Results: There was no association between miR-484 levels and fruit intake frequency. Categorized miR-484 levels and fruit consumption were inversely and independently associated with the likelihood of incident T2DM. Analysis of the interaction effect suggests the presence of both positive multiplicative and additive interactions between miR-484 categories and fruit consumption frequency. Conclusions: Our study demonstrates a protective effect of daily fruit intake and high miR-484 levels regarding the risk of T2DM and supports the nutritional recommendations advocating daily fruit consumption. This study also suggests that the combined effect of low miR-484 levels and occasional fruit intake may increase the risk of T2DM beyond their independent effects.

Prevalence of diabetes and its associated factors in Cape Verde: an analysis of the 2020 WHO STEPS survey on non-communicable diseases risk factors

BACKGROUND

Type 2 diabetes mellitus (T2DM) represents a significant global health challenge, with its prevalence steadily rising across diverse populations. Understanding the factors associated with T2DM is crucial for effective prevention and management strategies. In Cape Verde, an archipelago nation off the coast of West Africa, the burden of T2DM is of particular concern, yet comprehensive studies investigating its determinants in this context remain sparse. This study aims to narrow the knowledge gap by assessing the prevalence of prediabetes, T2DM and its associated factors among the adult Cape Verdean population.

METHODS

Data from the WHO STEPs survey were used. We analyzed data from 1,936 adults aged 18-69 years. The outcome variable was diabetes status computed using the fasting blood glucose (mg/dl). The data was weighted before the analysis to account for sampling biases. Multinomial logistic regression models were computed in STATA version 18.

RESULTS

The overall prevalence of prediabetes and T2DM was 7.8% (95% CI: 6.1-9.9) and 3.9% (95% CI: 3.1-4.9), respectively. Increasing age was associated with a higher odd of prediabetes and T2DM with the highest odds observed among older adults [(prediabetes: AORs = 3.20, 95%CI: 1.88-5.54) and T2DM: AOR = 3.51, 95%CI: 1.71-7.18)]. Additionally, high total cholesterol levels were linked to increased odds of T2DM (AOR = 2.48, 95%CI: 1.64-3.76). Individuals who consumed less than four servings of vegetables daily had higher odds of T2DM (AOR = 1.74, 95%CI: 1.12-2.71) while being overweight/obese was associated with higher odds of prediabetes (AOR = 1.57, 95%CI: 1.10-2.23). Urban residents had higher odds of T2DM than rural residents (AOR = 1.92, 95%CI: 1.23-3.00). Also, higher educational attainment was associated with lower odds of T2DM only (AOR = 0.33, 95%CI: 0.12-0.88) but not statistically significant for prediabetes.

CONCLUSION

Based on the findings, we conclude that ageing, overweight/obesity, vegetable consumption and total cholesterol level are important predictors of pre-diabetes and T2DM in Cape Verde. As such, weight management and cholesterol management should be integral parts of T2DM prevention strategies. Additionally, clinicians and diabetes societies in Cape Verde must make the promotion of vegetable consumption a key component of their health advice and advocacy.

CLINICAL TRIAL NUMBER

Not applicable.

Cross-sectional associations between fruit and vegetable intake and successful ageing across six countries: findings from the WHO Study on global AGEing and adult health (SAGE)

OBJECTIVE

This study develops successful ageing profiles across six low- and middle-income countries (LMIC) and examines associations with fruit and vegetable (F&V) intake.

DESIGN

A cross-sectional analysis was conducted in mid-aged and older adults from the WHO Study of Global Ageing. Participants without chronic disease, cognitive impairment, depression or disability and with good physical, cardiovascular and respiratory function were considered to have successfully aged. Associations between F&V intake (serves/d) and successful ageing were examined using log-binomial regression adjusting for key confounders.

SETTING

China, Ghana, India, Mexico, Russia and South Africa.

PARTICIPANTS

A total of 28 785 men and women aged 50 years and over.

RESULTS

Successful ageing ranged from 4 % in Mexico to 15 % in China. After adjustment, only Ghana showed an association between fruit intake and successful ageing, with an inverse association identified (prevalence ratio (PR) = 0·87, 95 % CI 0·78, 0·98). An inverse association between vegetable intake and successful ageing was found in China (0·97, 0·95, 0·98) but no other country. An inverse association was shown for both China (0·98, 0·96, 0·99) and Ghana (0·92, 0·84, 1·00) when considering fruit and vegetables combined.

CONCLUSIONS

Associations between F&V intake and successful ageing are inconsistent. Further studies on LMIC countries are needed to meet the challenges of the ageing population.

High-quality fruit and vegetable characterized by cardiometabolic biomarkers and its relation to major chronic disease risk: results from 3 prospective United States cohort studies

BACKGROUND

The current guidelines recommend a specified total serving of fruits and vegetables (FV). However, how differences in their nutritional quality of specific FV influence overall health remains unclear.

OBJECTIVES

To identify high-quality FV using 14 cardiometabolic biomarkers, and assess their consumption, alongside overall FV intake, with chronic disease risk.

METHODS

We used data from 3 prospective cohorts, Health Professionals Follow-up Study, Nurses' Health Study (NHS), and NHSII. Diet was assessed at baseline and updated every 4 y. Biomarker analysis was conducted on 41,714 participants using generalized linear models. Metabolic quality was ascertained by each FV's association with biomarkers. Major chronic disease risk analysis involved 207,241 participants followed for 32 y with Cox proportional hazards models. We also analyzed atherosclerotic cardiovascular disease (ASCVD), type 2 diabetes (T2D), cancer, and chronic obstructive pulmonary disease (COPD) as secondary outcomes.

RESULTS

Of 52 FV items, 19 were identified as high-metabolic quality (top 5: apples/pears, iceberg/head lettuce, raw spinach, alfalfa sprouts, and eggplant/summer squash). In disease risk analysis, 60,712 major chronic disease events were recorded. A higher proportion of high-metabolic quality FV intake was associated with lower chronic disease risk across total FV quantity levels. In each quantity level stratum (quartiles Q1-Q4), comparing the highest to the lowest quality proportion quartiles, the hazard ratio (HR) (95% confidence interval [CI]) were 0.85 (0.81-0.90), 0.86 (0.82-0.90), 0.84 (0.80-0.89), and 0.89 (0.84-0.94), all P-trend < 0.001. Patterns were similar for ASCVD, T2D, and COPD but less consistent for cancer. High total FV intake, if consisting mostly of neutral or low-metabolic quality items, was not associated with lower chronic disease risk. For diabetes specifically, these were associated with significantly higher risk [quantity-Q3, HR: 1.13 (1.05, 1.22); quantity-Q4, HR: 1.17 (1.07, 1.28)].

CONCLUSIONS

Our findings indicate the importance of considering both quality and quantity of FV for health, and support dietary guidelines to emphasize high-metabolic quality FV consumption alongside overall intake.

Are organics more nutritious than conventional foods? A comprehensive systematic review

The growing consumer interest fueled by the belief in the superiority of organic foods raises questions about their actual nutritional superiority over conventional ones. This assumption remains a controversial issue. The present study addresses scientific evidence to clarify this controversy and provide relevant insights for informed decision-making regarding dietary choices. We collected 147 scientific articles containing 656 comparative analyses based on 1779 samples of 68 vegetable, fruit, and other (cereals, pulses, etc.) foods, 22 nutritional properties, and nine residues. Results show that in 191 (29.1%) comparisons, there were significant differences between organic and conventional foods. In a similar quantity of cases (190; 29.0%), there were divergences in the results since some studies reported significant differences while others did not. Finally, most of the comparative analyses (275; 41.9%) showed no significant difference between organic and conventional foods. Therefore, the results herein show no generalizable superiority of organic over conventional foods. Claims for nutritious advantages would eventually be applied to specific comparisons, depending on the food type and nutritional parameter.

Prospective association between fruit and vegetable intake and the risk of type 2 diabetes amongst Chinese adults: the China Health and Nutrition Survey

This study aimed to prospectively explore the relationship between fruit and vegetable intake (FVI) and type 2 diabetes (T2D) risk amongst 13,175 Chinese adults. Cox proportional hazards models were used to estimate the hazard ratios (HRs) of T2D events in relation to FVI. Results showed that the highest quintile of FVI was inversely associated with T2D risk in men (HR = 0.72, 95% CI: 0.50, 0.98) and women (HR = 0.74, 95% CI: 0.55, 0.97), whereas no such associations were observed between total vegetable intake and T2D in either men (HR = 0.92, 95% CI: 0.65, 1.26) or women (HR = 1.02, 95% CI: 0.77, 1.38). In addition, greater fruit intake was inversely associated with T2D risk in men (HR = 0.42, 95% CI: 0.28, 0.63) and women (HR = 0.64, 95% CI: 0.45, 0.90). Overall, FVI and total fruit intake were inversely associated with T2D risk amongst Chinese adults.

Probiotic-fortified fruit juices: Health benefits, challenges, and future perspective

Consumers' growing interest in using foods that improve health has motivated researchers and the food industry to develop new functional products, such as foods containing probiotics or live microbes. Probiotics have functional attributes that could satisfy most basic nutritional and therapeutic supplementation requirements. These microbes positively respond to clinical therapies against diseases and illnesses such as rotavirus-associated diarrhea, irritable bowel syndrome, and food allergies. Moreover, the role of probiotics in the prevention and treatment of obesity, diabetes, cancer, and diseases related to pathogenic microbes is an exciting and rapidly advancing research arena. Probiotic supplementation usually involves dairy products. However, because of the growing number of individuals affected by lactose intolerance and/or vegans, other food matrices like fruits, vegetables, cereals, and so on, have been studied as potential carriers for these microorganisms, presenting an alternative and better source in the process of assessing novel probiotic strains. The present review discusses the various factors affecting the survival of probiotics during storage in fruit juices, the possible effect of probiotics on sensory attributes and the overall acceptance of the products, and future technologies to improve the viability of probiotics.

Prevalence and characteristics of metabolic syndrome and its components among adults living with and without HIV in Nigeria: a single-center study

BACKGROUND

Persons living with HIV (PLHIV) now live longer due to effective combination antiretroviral therapy. However, emerging evidence indicates that they may be at increased risk for some cardiometabolic disorders. We compared the prevalence of metabolic syndrome (MetS) and its component disorders between persons living with and without HIV in Nigeria.

METHODS

This was a cross-sectional analysis of baseline data from a prospective cohort study of non-communicable diseases among PLHIV along with age- and sex-matched persons without HIV (PWoH) at the University of Abuja Teaching Hospital Nigeria. We collected sociodemographic and clinical data, including anthropometric measures and results of relevant laboratory tests. MetS was defined using a modification of the third report of the National Cholesterol Education Program Adult Treatment Panel (NCEP ATP III) criteria.

RESULTS

Of the 440 PLHIV and 232 PWoH, women constituted 50.5% and 51.3% respectively. The median age of the PLHIV was 45 years while that of the PWoH was 40 years. The prevalence of MetS was 30.7% (95% CI: 26.4%, 35.2%) and 22.8% (95% CI: 17.6%, 28.8%) among the PLHIV and PWoH respectively (P = 0.026). Independent associations were found for older age (P < 0.001), female sex (P < 0.001), family history of diabetes (P < 0.001), family history of hypertension (P = 0.013) and alcohol use (P = 0.015). The prevalence of component disorders for PLHIV versus PWoH were as follows: high blood pressure (22.3% vs 20.3%), prediabetes (33.8% vs 21.1%), diabetes (20.5% vs 8.2%), high triglycerides (24.5% vs 17.2%), low HDL-Cholesterol (51.1% vs 41.4%), and abdominal obesity (38.4% vs 37.1%). Adjusting for age and sex, prediabetes, diabetes, and low HDL-Cholesterol were significantly associated with HIV status. Duration on antiretroviral therapy, protease inhibitor-based regimen, CD4 count, and viral load were associated with some of the disorders mostly in unadjusted analyses.

CONCLUSION

We found a high burden of MetS and its component disorders, with significantly higher prevalence of dysglycemia and dyslipidemia among PLHIV as compared to PWoH. Integration of strategies for the prevention and management of MetS disorders is needed in HIV treatment settings.

The dose-response relationship of fruit and vegetable intake and risk of type 2 diabetes among rural China: The Henan Rural Cohort study

AIMS

To explore the dose-response relationship of fruit and vegetable (F&V) intake and type 2 diabetes (T2D) risk in rural China.

METHODS

A total of 38798 adults were recruited from the Henan Rural Cohort Study. F&V intake was assessed by a validated food-frequency questionnaire. Logistic regression and restricted cubic splines analysis were conducted to calculate the odds ratio (OR) for T2D relative to F&V intake and investigate the dose-response relationship.

RESULTS

Higher intake of fruit or combined F&V was in connection with a lower risk of T2D, after adjusting for multiple confounders. After analyzing the dose-response relationship, we found that the odds of T2D decreased significantly with fruit consumption ≥ 260 g/day or F&V intake between 600 and 1000 g/day. And in subgroup analysis, we found that the negative correlation between fruit consumption and T2D was more pronounced in non-current smokers and non-current drinkers.

CONCLUSIONS

High intake of fruit alone or combined F&V is related to a reduced risk of T2D in rural China. Fruit intake ≥ 260 g/day and total F&V consumption of 600-1000 g/day should be encouraged to promote good health.

EAT-Lancet Healthy Reference Diet score and diabetes incidence in a cohort of Mexican women

To improve the health of our planet and develop sustainable food policies, it is important to understand the health impact of a diet pattern that considers planetary and population health. We used data from the Mexican Teachers' Cohort (MTC) to estimate the association between the EAT-Lancet healthy reference diet (EAT-HRD) and type 2 diabetes (T2D) incidence. We included 74,671 women aged ≥25 years, free of T2D at baseline. A validated food frequency questionnaire (FFQ) was used to assess dietary intake. We created an EAT-HRD score based on 15 food groups recommended by the EAT-Lancet Commission (range from 0 to 15). T2D cases were identified through self-report and cross-linkage with clinical and administrative databases. We used Cox proportional hazards models to estimate the association between categories of the EAT-HRD score with T2D incidence. During a median follow-up of 2.16 y (IQR 1.8-4.3 y), we identified 3241 T2D incident cases. The median EAT-HRD score was 6 (IQR 5-7). In multivariable analyses, when comparing extreme categories, higher adherence to the EAT-HRD score was associated with lower T2D incidence (HR 0.90; 95% CI 0.75, 1.10), yet, the estimation was imprecise. Compared to those who did not meet the EAT-HRD recommendations, adhering to the red meat, legumes, and fish recommendations was associated with lower T2D incidence. Meeting the recommendation of dairy and added sugars was associated with an increased incidence of T2D. Higher adherence to a diet designed to promote environmental and human health may help prevent T2D incidence among women in a middle-income country.

Vegetable, but Not Potato, Intake Is Associated With a Lower Risk of Type 2 Diabetes in the Danish Diet, Cancer and Health Cohort

OBJECTIVE

To examine the relationship between intake of vegetables/potatoes and incident type 2 diabetes (T2D) and explore whether the relationship between vegetable intake and incident T2D is mediated by baseline BMI.

RESEARCH DESIGN AND METHODS

Cross-sectional associations between exposure (baseline intake of total vegetables, vegetable subgroups, and potatoes) and baseline BMI were assessed by multivariable-adjusted linear regression models. Associations between exposure and incident T2D were examined by multivariable-adjusted Cox proportional hazards models. Mediation by BMI was quantified through exploration of natural direct and indirect effects.

RESULTS

Among 54,793 participants in the Danish Diet, Cancer and Health cohort, 7,695 cases of T2D were recorded during a median follow-up of 16.3 years. Participants in the highest total vegetable intake quintile (median 319 g/day) had a 0.35 kg/m2 (95% CI -0.46, -0.24) lower BMI and a 21% (95% CI 16, 26%) lower risk of incident T2D after multivariable adjustment compared with those in the lowest quintile (median 67 g/day). Baseline BMI mediated ∼21% of the association between vegetable intake and incident T2D. Participants in the highest compared with the lowest (median 256 vs. 52 g/day) potato intake quintile had a 9% (95% CI 2, 16%) higher risk of T2D after multivariable adjustment, with no association found after accounting for underlying dietary pattern. Of the vegetable subclasses, higher intake of green leafy and cruciferous vegetables was associated with a statistically significantly lower risk of T2D.

CONCLUSIONS

The findings provide evidence that a higher vegetable, but not potato, intake might help mitigate T2D risk, partly by reducing BMI.

Whole fresh fruit intake and risk of incident diabetes in different glycemic stages: a nationwide prospective cohort investigation

PURPOSE

Fruit intake is beneficial to several chronic diseases, but controversial in diabetes. We aimed to investigate prospectively the associations of whole fresh fruit intake with risk of incident type 2 diabetes (T2D) in subjects with different glucose regulation capacities.

METHODS

The present study included 79,922 non-diabetic participants aged ≥ 40 years from an ongoing nationwide prospective cohort in China. Baseline fruit intake information was collected by a validated food frequency questionnaire. Plasma HbA1c, fasting and 2 h post-loading glucose levels were measured at both baseline and follow-up examinations. Cox proportional hazards models were used to calculate hazard ratio (HR) and 95% confidence intervals (CI) for incident diabetes among participants with normal glucose tolerance (NGT) and prediabetes, after adjusted for multiple confounders. Restricted cubic spline analysis was applied for dose-response relation.

RESULTS

During a median 3.8-year follow-up, 5886 (7.36%) participants developed diabetes. Overall, we identified a linear and dose-dependent inverse association between dietary whole fresh fruit intake and risk of incident T2D. Each 100 g/d higher fruit intake was associated with 2.8% lower risk of diabetes (HR 0.972, 95%CI [0.949-0.996], P = 0.0217), majorly benefiting NGT subjects with 15.2% lower risk (HR 0.848, 95%CI [0.766-0.940], P = 0.0017), while not significant in prediabetes (HR 0.981, 95%CI 0.957-4.005, P = 0.1268). Similarly, the inverse association was present in normoglycemia individuals with a 48.6% lower risk of diabetes when consuming fruits > 7 times/week comparing to those < 1 time/week (HR 0.514, 95% CI [0.368-0.948]), but not in prediabetes (HR 0.883, 95% CI [0.762-1.023]).

CONCLUSION

These findings suggest that higher frequency and amount of fresh fruit intake may protect against incident T2D, especially in NGT, but not in prediabetes, highlighting the dietary recommendation of higher fresh fruit consumption to prevent T2D in normoglycemia population.

Effects of green tea polyphenol extract and epigallocatechin-3-O-gallate on diabetes mellitus and diabetic complications: Recent advances

Diabetes mellitus is one of the major non-communicable diseases accounting for millions of death annually and increasing economic burden. Hyperglycemic condition in diabetes creates oxidative stress that plays a pivotal role in developing diabetes complications affecting multiple organs such as the heart, liver, kidney, retina, and brain. Green tea from the plant Camellia sinensis is a common beverage popular in many countries for its health benefits. Green tea extract (GTE) is rich in many biologically active compounds, e.g., epigallocatechin-3-O-gallate (EGCG), which acts as a potent antioxidant. Recently, several lines of evidence have shown the promising results of GTE and EGCG for diabetes management. Here, we have critically reviewed the effects of GTE and EGCC on diabetes in animal models and clinical studies. The concerns and challenges regarding the clinical use of GTE and EGCG against diabetes are also briefly discussed. Numerous beneficial effects of green tea and its catechins, particularly EGCG, make this natural product an attractive pharmacological agent that can be further developed to treat diabetes and its complications.

Health effects associated with vegetable consumption: a Burden of Proof study

Previous research suggests a protective effect of vegetable consumption against chronic disease, but the quality of evidence underlying those findings remains uncertain. We applied a Bayesian meta-regression tool to estimate the mean risk function and quantify the quality of evidence for associations between vegetable consumption and ischemic heart disease (IHD), ischemic stroke, hemorrhagic stroke, type 2 diabetes and esophageal cancer. Increasing from no vegetable consumption to the theoretical minimum risk exposure level (306-372 g daily) was associated with a 23.2% decline (95% uncertainty interval, including between-study heterogeneity: 16.4-29.4) in ischemic stroke risk; a 22.9% (13.6-31.3) decline in IHD risk; a 15.9% (1.7-28.1) decline in hemorrhagic stroke risk; a 28.5% (-0.02-51.4) decline in esophageal cancer risk; and a 26.1% (-3.6-48.3) decline in type 2 diabetes risk. We found statistically significant protective effects of vegetable consumption for ischemic stroke (three stars), IHD (two stars), hemorrhagic stroke (two stars) and esophageal cancer (two stars). Including between-study heterogeneity, we did not detect a significant association with type 2 diabetes, corresponding to a one-star rating. Although current evidence supports increased efforts and policies to promote vegetable consumption, remaining uncertainties suggest the need for continued research.

Association between Adequate Fruit and Vegetable Intake and CVDs-Associated Risk Factors among the Malaysian Adults: Findings from a Nationally Representative Cross-Sectional Study

This study aimed to investigate the relationship between adequate fruit and vegetable intake, and cardiovascular diseases (CVDs)-associated risk factors (i.e., diabetes, hypertension and hypercholesterolemia) among Malaysian adults without history of chronic diseases. We analyzed the data from 11,172 Malaysian adults (i.e., 5554 male and 5618 female), who participated in the population-based National Health and Morbidity Survey 2015. Multiple logistic regression was employed to determine the relationship between adequate daily intake of fruit and vegetables (i.e., ≥5 servings per day) and undiagnosed diabetes, undiagnosed hypertension, and undiagnosed hypercholesterolemia, after adjustment for sociodemographic characteristics and lifestyle risk factors. The mean age (±SE) of these participants was 40.79 (±0.17) years old. Our data demonstrated an adequate daily intake of fruit and vegetables was inversely associated with undiagnosed hypercholesterolemia (adjusted OR: 0.71; 95% CI: 0.51–0.98). Further analyses demonstrated an inverse association between the adequate daily intake of vegetables alone and undiagnosed hypertension (adjusted OR: 0.71; 95% CI: 0.51–0.98). The findings from this study suggest the need for a holistic public health approach to reinforce public awareness about diet-related diseases, which will eventually aid in the prevention of CVDs among Malaysian adults in the long run.

Fruit and vegetable intake and risk of prediabetes and type 2 diabetes: results from a 20-year long prospective cohort study in Swedish men and women

Purpose

To investigate the association between fruit and vegetable intake (FVI) and the risk of developing prediabetes and type 2 diabetes (T2D) in a Swedish prospective cohort study.

Methods

Subjects were 6961 men and women aged 35–56 years old at baseline, participating in the Stockholm Diabetes Prevention Program cohort. By design, the cohort was enriched by 50% with subjects that had family history of diabetes. Anthropometric measurements, oral glucose tolerance tests and questionnaires on lifestyle and dietary factors were carried out at baseline and two follow-up occasions. Cox proportional hazard models were used to estimate hazard ratios with 95% CIs.

Results

During a mean follow-up time of 20 ± 4 years, 1024 subjects developed T2D and 870 prediabetes. After adjustments for confounders, the highest tertile of total FVI was associated with a lower risk of developing T2D in men (HR 0.76, 95% CI 0.60–0.96). There was also an inverse association between total fruit intake and prediabetes risk in men, with the HR for the highest tertile being 0.76 (95% CI 0.58–1.00). As for subtypes, higher intake of apples/pears was inversely associated with T2D risk in both sexes, whereas higher intakes of banana, cabbage and tomato were positively associated with T2D or prediabetes risk in either men or women.

Conclusion

We found an inverse association between higher total FVI and T2D risk and between higher fruit intake and prediabetes risk, in men but not in women. Certain fruit and vegetable subtypes showed varying results and require further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-022-02871-6.

A Mendelian Randomization Study of the Effect of Tea Intake on Type 2 Diabetes

Background: The association reported between tea intake and type 2 diabetes (T2D) is inconsistent in previous studies and remains controversial. We aimed to explore the causal relationship between tea intake, T2D, and glycemic traits including hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), fasting serum insulin (FSI), and homeostasis model of insulin resistance (HOMA-IR) levels. Methods: A 2-sample Mendelian randomization (MR) was performed using summary statistics from large-scale genome-wide association studies of tea intake from the UK Biobank, T2D from the DIAGRAM consortium, and glycemic traits from the Magic consortium. The findings were verified through sensitivity analyses using various MR methods with different model assumptions and by comprehensively evaluating the influence of pleiotropy effects and outliers. Results: With the use of a two-sample MR with inverse variance-weighted method, the odds ratio per unit SD change of tea intake (SD: 2.85 cups/day) for T2D, HbA1c, FPG, FSI, and HOMA-IR levels was 0.949 (95% CI 0.844-1.067, p = 0.383), 0.994 (95% CI 0.975-1.013, p = 0.554), 0.996 (95% CI 0.978-1.015, p = 0.703), 0.968 (95% CI 0.948-0.986, p = 0.001), and 0.953 (95% CI 0.900-1.009, p = 0.102), respectively. The results were consistent with those of the other six methods that we used with different model assumptions, suggesting that the findings were robust and convincing. We also performed various sensitivity analyses for outlier removal, pleiotropy detection, and leave-one-out analysis. Conclusion: Our MR results did not support the causal effect of tea intake on T2D and crucial glycemic traits. These findings suggest that previous observational studies may have been confounded.

Association of fruit and vegetable color with incident diabetes and cardiometabolic risk biomarkers in the United States Hispanic/Latino population

Background

Color groups of fruits and vegetables (FV) are part of a healthy diet, but evidence for an association with cardiometabolic outcomes is inconsistent.

Objective

To examine the association between intake of FV of different colors with incident diabetes and cardiometabolic risk biomarkers among U.S. Hispanics/Latinos.

Subjects/methods

We used data from 9206 adults ages 18–74 years who were free of diabetes at baseline (2008–2011) and had follow-up data at visit 2 (2014–2017) in the Hispanic Community Health Study/Study of Latinos (HCHS/SOL), a multicenter, prospective cohort study of self-identified Hispanics/Latinos. Dietary intake was assessed using two 24 h recalls at baseline. FV were categorized into five color groups: green, white, yellow/orange, red/purple, and uncategorized. Diabetes was defined based on laboratory measures and self-reported antihyperglycemic medication. We used survey logistic regression models to evaluate the association between FV color groups and incident diabetes and survey linear regression models to evaluate the association of FV color groups with cardiometabolic risk biomarkers at visit 2.

Results

During ~6 years of follow-up, 970 incident cases of diabetes were documented. The red/purple FV color group was the least consumed (0.21 servings/day), whereas white FV were the most consumed (0.92 servings/day). For each serving of total FV intake, body mass index (BMI) was lower by 0.24% (p = 0.03) and insulin by 0.69% (p = 0.03). For each serving of red/purple FV intake, HDL was 1.59% higher (p = 0.04). For each serving of white FV intake (with potato), post-OGTT was 0.83% lower (p = 0.04) and triglycerides 1.43% lower (p = 0.04). There was no association between FV intake and incident diabetes.

Conclusions

Specific FV colors were associated with cardiometabolic benefits though the associations were of relatively small magnitudes. Dietary recommendations could consider varying colors of FV intake, especially white and red/purple color groups, for a healthy diet.

Combination of Texture-Induced Oral Processing and Vegetable Preload Strategy Reduced Glycemic Excursion but Decreased Insulin Sensitivity

This study aimed to investigate the effect of the oral processing of vegetables induced by texture modification on acute postprandial glycemic response (GR) and insulin response (IR) when co-ingested and ingested prior to a rice meal. In a randomized crossover trial, 14 healthy female subjects consumed (1) co-ingestion of soft broccoli and rice (SR); (2) co-ingestion of hard broccoli and rice (HR); (3) soft broccoli prior to rice (S+R); (4) hard broccoli prior to rice (H+R); (5) rice (R). Postprandial GR and IR was compared between test meals over a period of 180-min, and the oral processing behaviors were measured for each test food samples. Hard broccoli was observed to have a higher mastication time and chews than soft broccoli. All the broccoli meals resulted in reduced incremental peak glucose (IPG) and an increased incremental area under the insulin curve in 180 min (iAUC_0–180) compared with R. The S+R curbed the IPG by 40% with comparable HOMA-IR AUC_0–180 compared with R, while the H+R elevated the HOMA-IR AUC_0–180 by 62% more than that of R. In conclusion, the soft broccoli intake prior to a rice meal effectively attenuated postprandial GR, without lowering insulin sensitivity as its hard counterpart did.

Innovation as a Factor Increasing Fruit Consumption: The Case of Poland

Due to the low level of fruit consumption in relation to dietary recommendations in many European countries, including Poland, multidirectional actions should be taken to increase the consumption of these products. One of the ideas could be the introduction of innovative products. The main goal of the study is to determine the relationship between consumer propensity to purchase innovative products and the frequency of consumption of fruits and their preserves of consumers. The research sample consisted of 600 respondents who declared to consume fruit and were responsible for food shopping in their households. The results obtained indicate that consumers with a higher propensity to purchase innovative products consumed fruit and fruit preserves more. In addition, statistically significant differences were found between innovators and non-innovators in terms of income, expenditures on fruit purchases, places where fruit and fruit preserves were purchased and product characteristics that determined the purchase decision. The logistic regression results indicate that a higher frequency of supermarket/hypermarket and online shopping, a higher weekly spending on fruit and a greater importance attributed to the biodegradability of the packaging increased the favorability of innovation relatively to fruit products (by 23.8%, 31.4%, 32.7% and 21.6%, respectively). The relationships found may have important implications for both private and public stakeholders in the fruit and vegetable sector.

Fasting-Mimicking Diet Reduces Trimethylamine N-Oxide Levels and Improves Serum Biochemical Parameters in Healthy Volunteers

Elevated plasma levels of trimethylamine N-oxide (TMAO) have been proposed as a diet-derived biomarker of cardiometabolic disease risk. Caloric restriction is the most common dietary intervention used to improve cardiometabolic health; however, novel trends suggest a fasting-mimicking diet (FMD) as a more feasible alternative. FMD is a variation of intermittent fasting, based on caloric restriction and limitation of protein sources of animal origin, applied in daily cycles during a 5-day period. As TMAO is intensively produced by gut microbiota after the consumption of animal-derived products, we aim to investigate whether a 5-day FMD affects plasma TMAO levels and markers of metabolic health. To investigate whether an increase in vegetable intake possesses similar effects on TMAO levels and metabolic parameters, healthy volunteers (n = 24) were subjected to a 5-day FMD and 19 volunteers served as a reference group (VEG). This group of volunteers consumed an additional four servings of vegetables per day, but otherwise stayed on their usual diet. FMD resulted in a twofold decrease in plasma TMAO levels, which was not evident in the volunteers from the VEG group. Moreover, FMD led to a weight loss of 2.8 ± 0.2 kg and a subsequent reduction in BMI compared to baseline. The FMD group exhibited a significant elevation in plasma ketone bodies (14-fold compared to baseline) and a decrease in IGF-1 levels by 37 ± 8 ng/mL. Since fasting glucose and C-peptide levels decreased, all volunteers in the FMD group showed improved insulin sensitivity and a decreased HOMA-IR index. In contrast, in the VEG group, only a slight reduction in plasma levels of fasting glucose and triglycerides was noted. In conclusion, we show that FMD is a viable strategy to reduce plasma levels of TMAO by limiting caloric intake and animal-derived protein consumption. The reduction in the level of TMAO could be an additional benefit of FMD, leading to a reduced risk of cardiometabolic diseases.

Fruit and vegetable consumption and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective studies

BACKGROUND

The association between intake of fruit and vegetables and their subtypes, and the risk of type 2 diabetes has been investigated in several studies, but the results have been inconsistent.

OBJECTIVE

We conducted an updated systematic review and dose-response meta-analysis of prospective studies on intakes of fruit and vegetables and fruit and vegetable subtypes and the risk of type 2 diabetes.

DESIGN

PubMed and Embase databases were searched up to 20 October 2020. Prospective cohort studies of fruit and vegetable consumption and type 2 diabetes mellitus were included. Summary relative risks (RRs) and 95% CIs were estimated using a random effects model.

RESULTS

We included 23 cohort studies. The summary RR for high versus low intake and per 200 g/day were 0.93 (95% CI: 0.89 to 0.98, I²=0%, n=10 studies) and 0.98 (95% CI: 0.95 to 1.01, I²=37.8%, n=7) for fruit and vegetables combined, 0.93 (95% CI: 0.90 to 0.97, I²=9.3%, n=20) and 0.96 (95% CI: 0.92 to 1.00, I²=68.4%, n=19) for fruits and 0.95 (95% CI: 0.88 to 1.02, I²=60.4%, n=17) and 0.97 (95% CI: 0.94 to 1.01, I²=39.2%, n=16) for vegetables, respectively. Inverse associations were observed for apples, apples and pears, blueberries, grapefruit and grapes and raisins, while positive associations were observed for intakes of cantaloupe, fruit drinks, fruit juice, brussels sprouts, cauliflower and potatoes, however, most of these associations were based on few studies and need further investigation in additional studies.

CONCLUSIONS

This meta-analysis found a weak inverse association between fruit and vegetable intake and type 2 diabetes risk. There is indication of both inverse and positive associations between intake of several fruit and vegetables subtypes and type 2 diabetes risk, however, further studies are needed before firm conclusions can be made.

The effects of high fructose fruits and honey on the serum level of metabolic factors and nonalcoholic fatty liver disease

Introduction

The effect of the natural sources of fructose such as high fructose fruits and honey on the risk of fatty liver is still challenging. This study aimed to compare the effect of fructose, high fructose fruits, and honey on the metabolic factors and non-alcoholic fatty liver disease (NAFLD).

Methods

Forty-four rats were divided into four groups including normal diet group, high fructose group (HF), high fructose fruits group (HFF), and honey group (HO). After 120 days of intervention, the levels of insulin resistance, hepatic enzyme, and lipid profile were measured. Also, the expression levels of the acetyl-coA carboxylase (ACC), sterol regulatory element-binding protein 1c (SREBP-1c), Interleukin 6 (IL-6), and transforming growth factor-beta (TGF-β) genes were assessed. In addition, a histopathologic assessment was performed on liver tissues.

Results

Insulin resistance (IR) increased significantly in the HF, HFF, and HO groups (All P < 0.05). The levels of liver enzymes was significantly increased only in the group receiving the HF regimen (P < 0.01). A significant decrease in total cholesterol and HDL-C (high density lipoprotein cholesterol) levels was found in HO group compared to the control group (P < 0.05). The expression levels of ACC and SREBP-1c genes in HF, HFF, and HO groups were significantly higher than the control group (All P < 0.05). The HF group had a greater increase in the level of gene expression of IL-6 and TGF-β (All P < 0.05). Histopathological assessment did not find any changes in fatty liver formation and inflammatory damage.

Conclusion

Consumption of fructose-rich honey and fruits improved the status of inflammatory markers and liver enzymes compared with the industrial fructose-rich products.

Nutritional Significance of Fruit and Fruit Products in the Average Polish Diet

The aim of the present study was to analyze the supply of energy, 19 nutrients, free sugars, and dietary fiber in the average Polish diet from fruit and fruit products. Our analysis is based on 2016 data from the national representative household budget survey conducted on a sample of 36,886 households, yielding a population of 99,230 individuals. Fruit and fruit products provided 3.12% of energy to the average diet in Poland with the highest share of bananas and apples. The highest significance of this food group was found for vitamin C (23.65%), including citrus fruits providing 8.03% of vitamin C, berries (5.97%), other fruits (3.45%), and apples (3.13%). The share of fruit and their products in the supply of free sugars is equally high and amounts to 23.52%. This means that apples provide 6.34% of free sugars, while other fruits also have a high supply of free sugars, including berries 3.68%, stone fruits 3.06%, bananas 2.56%, and citrus fruits 2.54%. The proportion of supply exceeding the percentage of energy (which was 3.12%) was obtained for carbohydrate (5.79%), and fiber (13.66%). The food group studied was particularly important (more than 5% share) in providing four minerals: potassium (8.59%), iron (5.07%), magnesium (5.51%), copper (8.81%), and three vitamins: vitamin C (23.65%), vitamin B6 (5.74%), and vitamin E (5.53%). The influence of sociodemographic and economic characteristics of households on the structure of energy and nutrient supply from fruit and fruit products was assessed using cluster analysis. There were four clusters characterized by different energy, nutrient, and fiber supply. The factors with the highest statistical significance on the supply of energy, nutrients, and fiber from fruit and fruit products were month of study, income, degree of urbanization, education, size of town, and land use. The obtained results concerning energy and nutrient supply from fruits and fruit products are important for the Polish society from the public health point of view, as indicated in the discussion of results and conclusions.

Changes in intake of dairy product subgroups and risk of type 2 diabetes: modelling specified food substitutions in the Danish Diet, Cancer and Health cohort

PURPOSE

We investigated the association between an increased intake of one dairy product subgroup at the expense of another within a 5-year period and the subsequent 10-year risk of type 2 diabetes.

METHODS

The cohort included 39,393 adults with two measurements of diet assessed using food frequency questionnaires (FFQ) administered in 1993-1997 and 1999-2003. Dairy products were milk (skimmed, semi-skimmed, whole fat), buttermilk, low-fat yogurt, whole-fat yogurt, cheese and butter. Type 2 diabetes cases were ascertained from the Danish National Diabetes Register. The pseudo-observation method was used to calculate risk differences (RD) with 95% confidence intervals (CI). The data were analysed in age strata to fulfil the assumption of independent entry.

RESULTS

Among participants aged 56-59 years at completion of the follow-up FFQ, increased intake of whole-fat yogurt in place of skimmed, semi-skimmed or whole-fat milk was associated with a reduced risk (RD% [95% CI]: - 0.8% [- 1.3, - 0.2]; - 0.6% [- 1,1, - 0.1]; - 0.7 [- 1.2, - 0.1]; per 50 g/d, respectively). Among participants aged 60-64 and 65-72, substitution of skimmed milk for semi-skimmed milk was associated with an increased risk of type 2 diabetes (0.5% [0.2, 0.7]; 0.4% [0.1, 0.7]; per 50 g/d, respectively). Similar patterns of associations were found after adjustment for potential mediators.

CONCLUSION

Our results suggest that substitution of whole-fat yogurt for milk among those aged 56-59 decreases risk of type 2 diabetes and substitution of skimmed milk for semi-skimmed milk may increase the risk among those aged 60-64 and 65-72.

Prevalence and Risk Factors of Type 2 Diabetes and Prediabetes Among 53,288 Middle-Aged and Elderly Adults in China: A Cross-Sectional Study

BACKGROUND

Diabetes is a metabolic disorder that causes a heavy burden on healthcare systems worldwide. The aim of this study was to determine the prevalence of type 2 diabetes and prediabetes and its associated factors among eight communities in Nanchong, China.

METHODS

This was an observational cross-sectional study conducted throughout eight communities in Nanchong, China. The participants were 53,288 individuals aged 45 years or older. The participants' characteristics, comorbidities, health behaviors, family history, and dietary intake were assessed. Multinomial logistic regression models were fitted to identify factors associated with type 2 diabetes and prediabetes.

RESULTS

The prevalence of diabetes and prediabetes was 13.9% (95% confidence interval [CI], 13.6-14.2) and 3.1% (95% CI, 2.9-3.2) of the population, respectively. After adjusting for other risk factors, advanced age, overweight, obesity, abdominal obesity, comorbidities, smoking, a family history of diabetes, and Chinese cooking vegetable intake were associated with an increased risk of type 2 diabetes and prediabetes.

CONCLUSION

The prevalence of type 2 diabetes in the Chinese population is rising compared with data from the past. The risk factors of type 2 diabetes and prediabetes identified in this study will aid the identification of individuals at a high-risk of diabetes and the implementation of effective health promotion programs and campaigns.

CLINICAL TRIAL REGISTRY NUMBER

ChiCTR-HOC-17013200.

Associations of carbohydrates and carbohydrate-rich foods with incidence of type 2 diabetes

Dietary carbohydrates have long been expected to be associated with risk of type 2 diabetes; however, the associations for many carbohydrates and carbohydrate-rich foods remain inconclusive. This study analysed associations between intakes of six types of carbohydrates and thirteen carbohydrate-rich foods with incident type 2 diabetes in 26 622 participants (61 % women) in the Malmö Diet and Cancer Study in southern Sweden. Dietary intake was assessed at baseline (1991-1996) by using a modified diet history method. During mean follow-up of 18 years, 4046 cases were identified. Adjusting for potential confounders (including lifestyle, BMI and dietary factors), comparing highest v. lowest quintile of intake, monosaccharides (hazard ratio (HR) 0·88; 95 % CI 0·79, 0·98; Ptrend = 0·02) and fruits (HR 0·91; 95 % CI 0·82, 1·01; Ptrend = 0·03) were inversely associated with incident type 2 diabetes, while disaccharides (HR 1·17; 95 % CI 1·04, 1·30; Ptrend = 0·002) and sweets (HR 1·09; 95 % CI 1·00, 1·19; Ptrend = 0·02) were positively associated. After stratification by sex, marmalade/honey/jam (HR 0·82; 95 % CI 0·72, 0·94; Ptrend < 0·001) and vegetables (HR 0·85; 95 % CI 0·73, 0·98; Ptrend = 0·06) were inversely associated with incident type 2 diabetes in men and chocolate (HR 1·26; 95 % CI 1·09, 1·46; Ptrend < 0·001) was positively associated in women. In conclusion, we identified inverse associations for intake of monosaccharides and fruits with type 2 diabetes risk, and positive associations for disaccharides and sweets. Additional sex-specific associations were also identified. Future studies are needed to explore these associations further.

Dietary fruit and vegetable intake, gut microbiota, and type 2 diabetes: results from two large human cohort studies

BACKGROUND

Little is known about the inter-relationship among fruit and vegetable intake, gut microbiota and metabolites, and type 2 diabetes (T2D) in human prospective cohort study. The aim of the present study was to investigate the prospective association of fruit and vegetable intake with human gut microbiota and to examine the relationship between fruit and vegetable-related gut microbiota and their related metabolites with type 2 diabetes (T2D) risk.

METHODS

This study included 1879 middle-age elderly Chinese adults from Guangzhou Nutrition and Health Study (GNHS). Baseline dietary information was collected using a validated food frequency questionnaire (2008-2013). Fecal samples were collected at follow-up (2015-2019) and analyzed for 16S rRNA sequencing and targeted fecal metabolomics. Blood samples were collected and analyzed for glucose, insulin, and glycated hemoglobin. We used multivariable linear regression and logistic regression models to investigate the prospective associations of fruit and vegetable intake with gut microbiota and the association of the identified gut microbiota (fruit/vegetable-microbiota index) and their related fecal metabolites with T2D risk, respectively. Replications were performed in an independent cohort involving 6626 participants.

RESULTS

In the GNHS, dietary fruit intake, but not vegetable, was prospectively associated with gut microbiota diversity and composition. The fruit-microbiota index (FMI, created from 31 identified microbial features) was positively associated with fruit intake (p < 0.001) and inversely associated with T2D risk (odds ratio (OR) 0.83, 95%CI 0.71-0.97). The FMI-fruit association (p = 0.003) and the FMI-T2D association (OR 0.90, 95%CI 0.84-0.97) were both successfully replicated in the independent cohort. The FMI-positive associated metabolite sebacic acid was inversely associated with T2D risk (OR 0.67, 95%CI 0.51-0.86). The FMI-negative associated metabolites cholic acid (OR 1.35, 95%CI 1.13-1.62), 3-dehydrocholic acid (OR 1.30, 95%CI 1.09-1.54), oleylcarnitine (OR 1.77, 95%CI 1.45-2.20), linoleylcarnitine (OR 1.66, 95%CI 1.37-2.05), palmitoylcarnitine (OR 1.62, 95%CI 1.33-2.02), and 2-hydroglutaric acid (OR 1.47, 95%CI 1.25-1.72) were positively associated with T2D risk.

CONCLUSIONS

Higher fruit intake-associated gut microbiota and metabolic alteration were associated with a lower risk of T2D, supporting the public dietary recommendation of adopting high fruit intake for the T2D prevention.

Association of plasma biomarkers of fruit and vegetable intake with incident type 2 diabetes: EPIC-InterAct case-cohort study in eight European countries

OBJECTIVE

To investigate the association of plasma vitamin C and carotenoids, as indicators of fruit and vegetable intake, with the risk of type 2 diabetes.

DESIGN

Prospective case-cohort study.

SETTING

Populations from eight European countries.

PARTICIPANTS

9754 participants with incident type 2 diabetes, and a subcohort of 13 662 individuals from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort of 340 234 participants: EPIC-InterAct case-cohort study.

MAIN OUTCOME MEASURE

Incident type 2 diabetes.

RESULTS

In a multivariable adjusted model, higher plasma vitamin C was associated with a lower risk of developing type 2 diabetes (hazard ratio per standard deviation 0.82, 95% confidence interval 0.76 to 0.89). A similar inverse association was shown for total carotenoids (hazard ratio per standard deviation 0.75, 0.68 to 0.82). A composite biomarker score (split into five equal groups), comprising vitamin C and individual carotenoids, was inversely associated with type 2 diabetes with hazard ratios 0.77, 0.66, 0.59, and 0.50 for groups 2-5 compared with group 1 (the lowest group). Self-reported median fruit and vegetable intake was 274 g/day, 396 g/day, and 508 g/day for participants in categories defined by groups 1, 3, and 5 of the composite biomarker score, respectively. One standard deviation difference in the composite biomarker score, equivalent to a 66 (95% confidence interval 61 to 71) g/day difference in total fruit and vegetable intake, was associated with a hazard ratio of 0.75 (0.67 to 0.83). This would be equivalent to an absolute risk reduction of 0.95 per 1000 person years of follow up if achieved across an entire population with the characteristics of the eight European countries included in this analysis.

CONCLUSIONS

These findings indicate an inverse association between plasma vitamin C, carotenoids, and their composite biomarker score, and incident type 2 diabetes in different European countries. These biomarkers are objective indicators of fruit and vegetable consumption, and suggest that diets rich in even modestly higher fruit and vegetable consumption could help to prevent development of type 2 diabetes.

Exploring the Diets of Adults with Obesity and Type II Diabetes from Nine Diverse Countries: Dietary Intakes, Patterns, and Quality

Background: Calorie-dense diet is a main driver of the global epidemics of obesity and type 2 diabetes (T2DM). While various dietary strategies and patterns are efficacious in reducing risk and improving glycemic control, dietary intake and diet quality have been inadequately studied among individuals who remain living in their native environments. There is also little published on dietary patterns of diverse ethnic, cultural, or regional populations. Objective: To explore dietary intakes, patterns and overall diet quality in adults with obesity and T2DM from diverse countries. We hypothesized that individuals sharing a common clinical phenotype (age, BMI, years since T2DM diagnosis and inadequate glycemic control) would demonstrate comparable high calorie “western” dietary patterns and low diet quality despite differences in geographic regions and cultures. Design: Diet data were acquired from 611 adults in Argentina, Germany, Poland, Serbia, Slovakia, Slovenia, Spain, Turkey and the USA via three 24-h diet recalls. Contribution of 168 foods to 14 primary food groups was confirmed by Spearman’s rank-order correlations and Principle Component Factor Analysis identified dietary patterns. Diet quality was assessed using the Healthy Eating Index 2015. Results: Eleven dietary patterns were extracted; the most common were a “Mediterranean-like” pattern shared by six countries and a “Calorie Dense” pattern shared by five countries. Also common were “Lacto-Vegetarian, “Pesco-Vegetarian,” and “Vegan” patterns. Only 2.1% of subjects had good diet quality (HEI-2015 score >80). Conclusions: The diet pattern data suggest that influences of more traditional region-specific diets remain. However, overall diet quality was poor and may contribute to inadequate glycemic control, possibly due to excess intake of high calorie/nutrient poor foods, which may be associated with global transitions occurring in the available food supply.

Fruit and vegetable intake is inversely associated with type 2 diabetes in Chinese women: results from the China Health and Nutrition Survey

This study aimed to evaluate the associations between fruit and vegetable (FV) intake and the risk of prediabetes or type 2 diabetes (T2D). It is a cross-sectional study that involved 6802 participants aged 18-65 years. Dietary intake and other variables were assessed by questionnaires. The prevalence of prediabetes and T2D was ascertained by self-report and analyses of fasting blood samples. In the multiple logistic regression models, FV intake was negatively associated the risk of T2D in women (OR = 0.45, 95% CI: 0.28, 0.71), whereas no such association was observed in men (OR = 0.98, 95% CI: 0.65, 1.47). Furthermore, FV consumption was inversely associated with prediabetes risk in men and women. Results suggested that higher intake of FV was associated with a decreased risk of T2D or prediabetes in Chinese women and a reduced risk of prediabetes in men only.

Acute effects of non-homogenised and homogenised vegetables added to rice-based meals on postprandial glycaemic responses and in vitro carbohydrate digestion

The addition of vegetable to carbohydrate-based meals was shown to contribute to glycaemic management. The aim of this study was to investigate the impact of homogenisation on vegetables added to rice meals in terms of acute glycaemic responses (GR). In a randomised crossover trial, sixteen healthy volunteers completed thirteen test sessions, which included two sessions for glucose control, two for rice and nine for different vegetable-rice mixed meals: cooked pak choi and cooked rice (CP+R); cooked cauliflower and cooked rice (CC+R); cooked eggplant and cooked rice (CE+R); and their homogenised counterparts, both raw or cooked. Postprandial GR tests, in vitro carbohydrate digestion and chemical analyses were carried out for each test meal. Compared with pure rice, CE+R, CP+R and CC+R meals achieved significantly lower glycaemic indexes (GI) of 67, 71 and 73, whereas their homogenised counterparts failed to show significant difference with rice. The hydrolysis indexes (HI) of CE+R, CP+R and CC+R were 69·6, 83·8 and 80·6 % of the HI of the rice control. CE had the greatest effect on lowering the GI, the incremental area under the blood glucose curve from 0 to 120 min, the peak glucose value, the maximum amplitude of glucose excursion in 0-120 min (MAGE0 -120), the HI and rapid available starch. Both in vitro and in vivo tests demonstrated that incorporating non-homogenised cooked vegetables into a rice meal could slow the carbohydrate digestion and improve postprandial GR. Texture properties of vegetable may play an important role in underlying glycaemic control mechanisms.

Nature's bountiful gift to humankind: Vegetables & fruits & their role in cardiovascular disease & diabetes

Fruits and vegetables (FVs) are recognized as healthy constituents of diet and a sustainable solution to the existing twin burden of micronutrient deficiencies and non-communicable diseases in developing and developed countries. In general, FVs are nutrient dense foods low in energy, containing varying amounts of vitamins and minerals including carotenoids, B vitamins, vitamin C, iron, zinc, potassium, calcium, magnesium and fibre. These are abundantly rich in phytochemicals that function as antioxidants, anti-atherosclerotic and anti-inflammatory agents. This review summarizes some epidemiological, prospective cohort and intervention studies on the health benefits of FVs in relation to cardiovascular disease, obesity and diabetes. The rich varieties of FVs available, their composition, production scenario in India, dietary intake and trends over time, barriers to sufficient intake mainly sociocultural, economic and horticulture environment, policies for promotion and prevention of diseases are considered.

Association between fruit and vegetable consumption and risk of metabolic syndrome determined using the Korean Genome and Epidemiology Study (KoGES)

PURPOSE

This study examined the association between fruit and vegetable consumption and the risk of metabolic syndrome (MetS) and its components in middle-aged and older adults using data from the Korean Genome and Epidemiology Study.

METHODS

A total of 5688 participants aged 40-69 years without MetS at baseline were recruited and followed for 8 years. Fruit and vegetable consumption was assessed using a semi-quantitative food-frequency questionnaire at baseline and after 4 years. A multivariate Cox proportional hazards model was used to examine the risk of incident MetS and its components according to fruit and vegetable consumption.

RESULTS

A total of 2067 participants (1020 men and 1047 women) developed MetS during the 8-year follow-up period. Frequent fruit consumers (≥ 4 servings/day) had a lower risk of incident MetS than did rare consumers (< 1 serving/day) in both men and women (hazard ratio (HR) = 0.55, 95% CI 0.44-0.67, p < 0.0001 for men; HR = 0.57, 95% CI 0.47-0.70, p for trend < 0.0001 for women) after adjusting for confounders. Frequent fruit consumption was inversely associated with incidence of abdominal obesity, hypertriglyceridemia, and elevated blood pressure. Frequent vegetable consumption was inversely associated with a risk of hyperglycemia only in men (HR = 0.65, 95% CI 0.44-0.96, p for trend = 0.0275), but no association was observed with risk of incident MetS.

CONCLUSIONS

High fruit consumption was associated with a reduced risk of incident MetS and its components, whereas high vegetable consumption was associated with a reduced risk of incident hyperglycemia, but not with MetS in middle-aged and older adults.

Ambient fine particulate pollution associated with diabetes mellitus among the elderly aged 50 years and older in China

The linkage between ambient air pollution exposure and occurrence of diabetes mellitus is not well defined. This study examined the association between exposure to fine particles (PM_2.5) and the prevalence of diabetes among Chinese elderly people. We surveyed 11,504 adults aged ≥50 years in China, estimated the annual concentrations of ambient PM_2.5 using a satellite-based model of aerosol optical depth information. We employed a generalized mixed effects model to examine the association between PM_2.5 and the prevalence of diabetes and explored potential effect modifiers. We estimated diabetes burden attributable to ambient PM_2.5 if the observed association is indeed causal. The diabetes prevalence among the participants was 6.5% (n = 745). Our analysis found a statistically significant association between PM_2.5 and diabetes. The adjusted odds ratio was 1.27 (95% confidence interval (CI), 1.12, 1.43) for each 10 μg/m³ increment in ambient PM_2.5. Stratified analyses found a lower association among the participants with higher consumption of fruit. We estimated that 22.02% (95% CI: 8.59%, 43.29%) of the diabetes cases could be ascribable to ambient PM_2.5. Our finding suggests that PM_2.5 exposures could increase the risk of diabetes, and if causal, could be responsible for substantial burden of diabetes among the Chinese elderly; and higher intakes of fruit might reduce the harmful effects of PM_2.5, however, due to the limitation of the cross-sectional study design, more studies are warranted to confirm this observation.

Green leafy and cruciferous vegetable consumption and risk of type 2 diabetes: results from the Singapore Chinese Health Study and meta-analysis

Several previous prospective studies suggest that consumption of green leafy and cruciferous vegetables may lower the risk of type 2 diabetes (T2D). We investigated the association between consumption of different types of vegetables in relation to T2D risk in an Asian Population. We included 45 411 participants (age range: 45-74 years) of the Singapore Chinese Health Study (SCHS) free of diabetes, cancer or CVD at baseline (1993-1998). Dietary information was collected using a validated FFQ. Physician-diagnosed incident diabetes was reported at follow-up I (1999-2004) and II (2006-2010) interviews. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI of T2D risk. An updated meta-analysis was also conducted to summarise results for green leafy and cruciferous vegetables. During 494 741 person-years of follow-up, 5207 incident T2D occurred. After adjustment for potential confounders, neither total vegetables (top v. bottom quintile HR=1·08; 95 % CI 0·98, 1·18, P trend=0·66) nor specific vegetables including dark green leafy vegetables (HR=1·05; 95 % CI 0·96, 1·15, P trend=0·21) and cruciferous vegetables (HR=0·97; 95 % CI 0·88, 1·06, P trend=0·29) were substantially associated with risk of T2D. A meta-analysis (eleven studies with 754 729 participants and 58 297 cases) including the SCHS and all previous prospective studies suggested borderline significant inverse associations between green leafy (summary relative risk (RR)=0·91; 95 % CI 0·84, 1·00) and cruciferous vegetable consumption (RR=0·87; 95 % CI 0·76, 1·00) and T2D risk, with moderate-to-high heterogeneity. In conclusion, green leafy or cruciferous vegetable consumption was not substantially associated with risk of T2D in an Asian population. Meta-analysis of available cohort data indicated that evidence for a beneficial effect of green leafy or cruciferous vegetable consumption on T2D risk is not convincing.

Dietary Polyphenols, Mediterranean Diet, Prediabetes, and Type 2 Diabetes: A Narrative Review of the Evidence

Dietary polyphenols come mainly from plant-based foods including fruits, vegetables, whole grains, coffee, tea, and nuts. Polyphenols may influence glycemia and type 2 diabetes (T2D) through different mechanisms, such as promoting the uptake of glucose in tissues, and therefore improving insulin sensitivity. This review aims to summarize the evidence from clinical trials and observational prospective studies linking dietary polyphenols to prediabetes and T2D, with a focus on polyphenol-rich foods characteristic of the Mediterranean diet. We aimed to describe the metabolic biomarkers related to polyphenol intake and genotype-polyphenol interactions modulating the effects on T2D. Intakes of polyphenols, especially flavan-3-ols, and their food sources have demonstrated beneficial effects on insulin resistance and other cardiometabolic risk factors. Several prospective studies have shown inverse associations between polyphenol intake and T2D. The Mediterranean diet and its key components, olive oil, nuts, and red wine, have been inversely associated with insulin resistance and T2D. To some extent, these associations may be attributed to the high amount of polyphenols and bioactive compounds in typical foods conforming this traditional dietary pattern. Few studies have suggested that genetic predisposition can modulate the relationship between polyphenols and T2D risk. In conclusion, the intake of polyphenols may be beneficial for both insulin resistance and T2D risk.

Prevention of metabolic diseases: fruits (including fruit sugars) vs. vegetables

PURPOSE OF REVIEW

To discuss recent evidence from observational and intervention studies on the relationship between fruit and vegetable (F&V) consumption and metabolic disease.

RECENT FINDINGS

Observational studies have consistently demonstrated a modest inverse association between the intake of fruit and leafy green vegetables, but not total vegetables, and biomarkers of metabolic disease as well as incident type 2 diabetes mellitus. This is in contrast to limited evidence from recently published randomized controlled dietary intervention trials, which - in sum - suggests little to no impact of increased F&V consumption on biomarkers of metabolic disease.

SUMMARY

Evidence from observational studies that fruit and leafy green vegetable intake is associated with lower type 2 diabetes risk and better metabolic health could not be confirmed by dietary intervention trials. It is unclear whether this discrepancy is because of limitations inherent in observational studies (e.g., subjective dietary assessment methods, residual confounding) or due to limitations in the few available intervention studies (e.g., short duration of follow-up, interventions combining whole fruit and fruit juice, or lack of compliance). Future studies that attempt to address these limitations are needed to provide more conclusive insight into the impact of F&V consumption on metabolic health.