Effect of dietary fatty acid composition on substrate utilization and body weight maintenance in humans

Association of lipid composition with diabetic foot ulcer size and depth: a cross-sectional study on plant versus animal oils, cholesterol, and omega fatty acids

BACKGROUND

As no study has evaluated the association between fat intake and its components with diabetic foot ulcer (DFU) indices, our aim in the present cross-sectional study was to assess this association.

METHODS

A total of 300 participants with DFUs were enrolled in this cross-sectional study, which took place at the Diabetes Clinic of Tehran University of Medical Sciences. To assess dietary intake, three 24-h dietary recalls were conducted. In addition to dietary assessments, sociodemographic information, anthropometric measurements and physical activity levels factors were evaluated. The evaluation of foot ulcer indices, including the length, width, and depth, was performed by reviewing the patients' medical records. A physician assessed all the foot ulcer indices.

RESULTS

Intakes of total fat, saturated fatty acid (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) increased progressively from the lowest to highest tertile of fat intake (all p < 0.001). No significant associations were observed between foot ulcer dimensions (length, width, depth) and dietary fat intake, including plant/animal oils, cholesterol, omega-3/6, trans fats, or PUFA/SFA ratios (Ptrend > 0.05). However, the (PUFAs + MUFAs)/SFAs ratio showed a significant inverse association with ulcer length in the fully adjusted model (OR: 0.71 vs. 0.42; Ptrend = 0.04).

CONCLUSION

In conclusion, we observed significant associations between an increase in the (PUFAs + MUFAs) / (SFAs) ratio and a notable reduction in foot ulcer length after adjusting for confounders. Further research with larger sample sizes could yield more comprehensive insights.

Lycopene Supplemented Mediterranean Diet Ameliorates Experimental Autoimmune Encephalomyelitis (EAE) in Mice and Changes Intestinal Microbiome

This study aimed to determine the effects of the Mediterranean diet (MD) and lycopene on the development of EAE and on inflammatory markers. In the 43-day study, 72 female C57BL/6 mice were randomly divided into eight groups according to whether they were EAE or naive (control) mice, fed a Western diet or a MD, and whether they received lycopene. During the study, mice were fed ad libitum, and lycopene groups were given 10 mg/kg/day lycopene per mouse every other day for 28 days in oral gavage. The mice were scored for EAE, sacrificed and their spleen, lymph nodes, and spinal cords were removed. We observed slightly delayed EAE onset in the MD-Lyc group compared to the others, and the EAE clinical scores were also lower than in the other groups. T-cell counts in the spleen and lymph nodes of the MD-Lyc group were significantly lower than in other groups. The production of IFN-γ and IL-22 was higher than in the other groups. IL-17 A cytokine produced in the spleen was lower in the MD-Lyc group than in the other groups. In addition, the highest myelination score was seen in the MD-Lyc group. MD-Lyc group also had a unique microbiome profile compared with the remaining groups. In summary, MD and lycopene administration positively impacted EAE scores and myelination. However, more comprehensive studies at the in vitro and in vivo levels are needed to reveal the effect of this intervention on cell numbers in the CNS.

Polyphenol-Rich Snack Consumption during Endurance Exercise Training Improves Nitric Oxide Bioavailability but does not Improve Exercise Performance in Male Cyclists: A Randomised Controlled Trial

Background

Antioxidants and nitric oxide (NO) precursors may improve endurance exercise performance by reducing oxidative stress and increasing NO production. Almonds, dried grapes, and cranberries (AGC) are good sources of antioxidants and NO precursors.

Objectives

To determine whether AGC consumption improved physiological responses and endurance cycling time-trial performance in response to training.

Methods

After 1 wk of light training (LT), 96 male recreationally trained cyclists consumed 125 g of AGC or control (CON: isocaloric oat bar) daily during 2 wk of heavy training (HT) and a 2-wk taper (T). At the end of LT, HT, and T, endurance exercise performance (5-min cycling time-trial; 5CTT), NO bioavailability (plasma and urine nitrate and nitrite), oxidative stress [plasma F2-isoprostanes (F2-Isop)], muscle damage (creatine kinase) and subjective measures of wellbeing were assessed, as well as physiological responses during exercise at 70% maximal aerobic power output.

Results

Compared to LT, 5CTT performance was impaired at HT (d = -0.27, P = 0.01) and improved at T (d = 0.79, P < 0.001), with no difference between treatments (P > 0.81). Compared with CON, during submaximal exercise at 70%, maximal aerobic power output AGC demonstrated higher oxygen consumption (HT: d = 0.46; T: d = 0.38, P < 0.001) and lower respiratory exchange ratio (HT: d = -0.61; T: d = -0.23, P < 0.032). At HT, urine F2-Isop was higher compared with LT (d = 0.21, P = 0.036), but plasma F2-Isop was lower (d = -0.22, P = 0.008), with no difference between treatments. At HT, AGC had higher subjective energy concentrations (d = 0.21, P = 0.02) and urinary nitrite (d = 0.23, P = 0.03) compared with CON and higher creatine kinase (d = 0.24, P = 0.02) and less fatigue (d = -0.20; P = 0.05) at T.

Conclusions

Although not beneficial for 5CTT performance or exercise efficiency, AGC increases fat oxidation during exercise, NO bioavailability, and subjective energy concentrations, which may confer benefits for health and wellbeing.This trial was registered at www.anzctr.org.au as ACTRN12618000360213.

Biomarkers of dietary PUFA intake in childhood and adolescence in relation to cardiometabolic risk factors in young adulthood: a prospective cohort study in Sweden

BACKGROUND

PUFAs, especially from vegetable fat sources, have been suggested to contribute to weight regulation and be protective to cardiometabolic health. However, a few longitudinal studies on childhood exposure are available, with short follow-up time and conflicting results.

OBJECTIVES

To study the relationship between plasma proportions of PUFA in childhood and adolescence and cardiometabolic risk factors in young adulthood, such as obesity, body composition, blood pressure (BP), and blood lipids in a prospective cohort study.

METHODS

We included n = 688 participants of the BAMSE (Barn, Allergi, Miljö, Stockholm, Epidemiologi) cohort in Stockholm, Sweden, with data on plasma phospholipid proportions of n-3 and n-6 fatty acids [α-linolenic acid (ALA), EPA, docosapentaenoic acid, DHA, linoleic acid (LA), and arachidonic acid (AA)] at 8 and 16 y and body mass index (BMI), waist circumference, fat mass %, BP, and blood lipids at 24 y. Associations between PUFAs and cardiometabolic health outcomes were assessed with sex-stratified multivariable-adjusted linear and logistic regression models.

RESULTS

In females, LA and ALA at 16 y were inversely associated with BMI [B: -0.35 (-0.54, -0.17) and B: -6.1 (-11, -1.5), respectively], and similarly with waist circumference and fat mass at 24 y. Also in females, LA was inversely associated with BP, triglycerides, LDL-cholesterol), and total cholesterol (e.g., B -0.044 [-0.079, -0.0099] for LA at 16 y and LDL-cholesterol), whereas ALA was only inversely associated with LDL-cholesterol. No associations were found between long chain n-3 fatty acids or AA and any of the studied outcomes.

CONCLUSIONS

Plasma phospholipid proportions of LA and ALA, biomarkers of vegetable oil intake, during childhood and adolescence were inversely associated with measures of obesity and cardiometabolic health in young adulthood, with a potential sex difference. These findings accord with short-term feeding trials suggesting a possible preventive role of LA on body fat accumulation.

Association of quality and quantity of macronutrients intake with obesity, new anthropometric indices, lipid accumulation, and blood lipid risk index in Tehranian women

Background

This study examines the association between micronutrient intake, anthropometric indices, lipid accumulation, and blood lipid risk index among Tehranian women.

Methods

A cross-sectional study was conducted on 556 Tehranian women. Dietary intake was measured using a Food Frequency Questionnaire. Biochemical assessment and anthropometric indices were measured, and demographic information and physical activity were collected.

Results

Participants with the highest intake of carbohydrates were more prone to obesity. Conversely, those in the top tertile for protein intake had a lower likelihood of obesity and higher levels of lipid accumulation product (LAP). The highest fat consumers had a 63% decreased chance of having a high Castelli's Risk Index 1 (CRI-1). A higher glycemic index (GI) and glycemic load (GL) were linked to an increased probability of a high atherogenic coefficient (AC). Women in the top tertile of GL were significantly more likely to be obese and had lower odds for high LAP. Participants in the top tertile of aromatic amino acids/branched chain amino acids (AAA/BCAA) had significantly lower chances of high CRI-1 and a high atherogenic index of plasma (AIP). Those in the highest tertile of monounsaturated fatty acids/polyunsaturated fatty acids (MUFA/PUFA) had lower odds of obesity and high AIP.

Conclusions

The amount of carbohydrate (g) and protein intake (%), dietary GL, and the ratio of MUFA to PUFA were associated with obesity. The amount of fat intake (g) and AAA/BCAA indices were associated with CRI-1. LAP decreased with an increase in GL. AC increased with an increase in GI and GL. AAA/BCAA and MUFA/PUFA were associated with AIP.

Monounsaturated fat-rich diet reduces body adiposity in women with obesity, but does not influence energy expenditure and substrate oxidation: a parallel randomized controlled clinical trial

BACKGROUND

Obesity is an important and growing health problem whose treatment involves dietary changes. In this context, studying the role of macronutrients in weight loss is required in order to understand which strategies may be applied for weight loss. We aimed to evaluate the effects of diets rich in polyunsaturated (PUFAs) and monounsaturated fatty acids (MUFAs) on resting energy expenditure (REE), substrate oxidation, and weight loss in women with obesity.

METHODS

Randomized, controlled, single blind, parallel-group clinical trial was conducted for 60 days. Participants (n = 32) were divided into three groups: G1= normocaloric PUFAs-rich diet (12% of total energy expenditure (TEE), 10% of n-6 and up to 2% of n-3); G2= normocaloric MUFAs-rich diet (15-20% TEE); and G3= maintenance of the usual diet. Anthropometric and metabolic variables (REE and substrate oxidation by indirect calorimetry) were evaluated.

RESULTS

G2 decreased body weight (-1.92 ± 1.99 kg, P = 0.02), body mass index (BMI) (-0.69 ± 0.70 kg/m2; P = 0.02), waist circumference (WC) (-1.91 ± 1.82 cm; P = 0.02), and body fat (-1.14 ± 1.53 kg; P = 0.04).

CONCLUSION

MUFAs-rich diet reduces body weight, BMI, body fat, and WC.

CLINICAL TRIALS

NCT02656940.

CLINICAL TRIAL REGISTRATION

Clinical Trials: NCT02656940.

High Dietary Folic Acid Supplementation Reduced the Composition of Fatty Acids and Amino Acids in Fortified Eggs

AIMS

The study aimed to evaluate the effects of dietary folic acid (FA) on the production performance of laying hens, egg quality, and the nutritional differences between eggs fortified with FA and ordinary eggs.

METHODS

A total of 288 26-week-old Hy-Line Brown laying hens (initial body weights 1.65 ± 0.10 kg) with a similar weight and genetic background were used. A completely randomized design divided the birds into a control group and three treatment groups. Each group consisted of six replicates, with twelve chickens per replicate. Initially, all birds were fed a basal diet for 1 week. Subsequently, they were fed a basal diet supplemented with 0, 5, 10, or 15 mg/kg FA in a premix for a duration of 6 weeks.

RESULTS

Supplementation of FA could significantly (p < 0.05) enhance the FA content in egg yolks, particularly when 10 mg/kg was used, as it had the most effective enrichment effect. Compared to the control group, the Glu content in the 10 and 15 mg/kg FA groups showed a significant (p < 0.05) decrease. Additionally, the contents of Asp, Ile, Tyr, Phe, Cys, and Met in the 15 mg/kg FA group were significantly (p < 0.05) lower compared to the other groups. Adding FA did not have significant effects on the levels of vitamin A and vitamin E in egg yolk, but the vitamin D content in the 5 and 10 mg/kg FA groups showed a significant (p < 0.05) increase. Furthermore, the addition of FA did not have a significant effect on the levels of Cu, Fe, Mn, Se, and Zn in egg yolk. The dietary FA did not have a significant effect on the total saturated fatty acids (SFA) and polyunsaturated fatty acid (PUFA) content in egg yolk. However, the total monounsaturated fatty acid (MUFA) content in the 5 and 10 mg/kg groups significantly (p < 0.05) increased. These changes in nutritional content might be attributed to the increased very low-density lipoprotein (VLDL) protein content. The significant decrease in solute carrier family 1 Member 1 (SLC1A1), solute carrier family 1 Member 2 (SLC1A2), and solute carrier family 1 Member 3 (SLC1A3) gene expression compared to the control group appeared to be the reason for the decrease in amino acid content in egg yolk within the dietary FA group.

CONCLUSION

The findings suggest that the appropriate addition of FA can enhance the levels of MUFA and vitamin D in egg yolks, thereby improving their nutritional value. Excessive intake of FA can decrease the effectiveness of enriching FA in egg yolk and impact the enrichment of certain amino acids. The yolk of eggs produced by adding 10 mg/kg of FA to the feed contains the optimal amount of nutrients. This study informs consumers purchasing FA-fortified eggs.

A MUFA/carotenoid-rich oil ameliorated insulin resistance by improving inflammation and oxidative stress in obese rats

Obesity is associated with low-grade inflammation and oxidative stress, leading to insulin resistance and type II diabetes. Caryocar brasiliense pulp oil (pequi oil - PO) is rich in oleic acid and carotenoids and positively implicated in regulating inflammation and oxidative stress. This study investigated PO's antioxidant and anti-inflammatory effects in a diet-induced obesity model. Male Wistar rats were allocated into three experimental groups: Control (CD), Western Diet (WD), and Western Diet, with 27% of lard switched by PO (WDP). Metabolic, inflammatory, and oxidative stress biomarkers were evaluated after 12 weeks of diet protocols in liver and adipose tissue. WDP rats gained less body mass and epididymal fat, had less hepatic fat infiltration, and were more glucose-tolerant and insulin-sensitive than WD (p < 0.05). In the liver, the WDP group had the highest non-enzymatic antioxidant capacity, SOD and GPx activities, CAT, SOD II, and HSP72 expression compared to WD (p < 0.05). Adipose tissue IL-6 and TNF were reduced, and IL-10 was increased in WDP compared to WD (p < 0.05). Our data suggest that the partial replacement of lard by PO in a Western diet prevented visceral fat accumulation and contributed to reducing inflammation in adipose tissue and liver oxidative stress, improving obesity-related insulin resistance.

Machine Learning Approach to Comparing Fatty Acid Profiles of Common Food Products Sold on Romanian Market

Food composition issues represent an increasing concern nowadays, in the context of diverse food commodity varieties. The contents and types of fatty acids are a constant preoccupation among consumers because of their reflections of nutrition and health problems. This study aims to find the best tool for the rapid and reliable identification of similarities and differences among several food items from a fatty acid profile perspective. An acknowledged GC-FID method was considered, while, for a better interpretation of the analytical results, machine learning algorithms were used. It was possible to develop a recognition model able to simultaneously differentiate, with an accuracy of 79.3%, nine product types using the bagged tree ensemble model. The low number of samples or some similarities among the classes could be responsible for the wrong assignments that occurred, especially in the biscuit, wafer and instant soup classes. Better accuracies values of 95, 86.1, and 97.8% were obtained when the products were grouped into three categories: (1) sunflower oil, mayonnaise, margarine, and cream cheese; (2) biscuits, cookies, margarine, and wafers; and (3) sunflower oil, chips, and instant soup.

Lower Adherence to a Mediterranean Diet Is Associated with High Adiposity in Community-Dwelling Older Adults: Results from the Longevity Check-Up (Lookup) 7+ Project

High adiposity impacts health and quality of life in old age, owing to its association with multimorbidity, decreased physical performance, and frailty. Whether a high adherence to a Mediterranean diet (Medi-Diet) is associated with reduced body adiposity in older adults is unclear. The present study was conducted to assess the prevalence of high adiposity in a large sample of community-dwelling older adults. We also explored the relationship between whole-body adiposity estimated through relative fat mass (RFM) and Medi-Diet adherence. Data were obtained from the Longevity Check-up 7+ (Lookup7+) project database. RFM was estimated from anthropometric and personal parameters using a validated equation. RFM was categorized as high if ≥40% in women and ≥30% in men. Information on diet was collected using a food frequency questionnaire, while Medi-Diet adherence was assessed through a modified version of the Medi-Lite scoring system. Analyses were conducted in 2092 participants (mean age 73.1 ± 5.9 years; 53.4% women). Mean RFM was 39.6 ± 5.14% in women and 29.0 ± 3.6% in men. High adiposity was found in 971 (46.4%) participants and was more frequent in those with a low (54.2%) or moderate (46.4%) Medi-Diet adherence compared with the high-adherence group (39.7%, p < 0.001). Logistic regression indicated that older adults with high Medi-Diet adherence were less likely to have a high RFM. Other factors associated with a greater risk of having high adiposity were older age, female sex, and physical inactivity. Our findings support an association between healthy lifestyles, including a greater adherence to a Mediterranean-style diet, and lower body adiposity in older adults.

A low-carb diet increases fecal short-chain fatty acids in feces of obese women following a weight-loss program: randomized feeding trial

To compare fecal level of short-chain fatty acid (SCFA) and some serum inflammatory markers between the low-carbohydrate (LCD) and the habitual (HD) diet, subjects were enrolled from our previous study on the effect of LCD vs. HD on gut microbiota in obese women following an energy-restricted diet. Serum interleukin-6 (IL-6) significantly increased in the HD group (p < 0.001). Adjusted for the baseline parameters, fecal level of butyric, propionic, and acetic acid were significantly different between the LCD and HD groups (p < 0.001, p = 0.02, and p < 0.001, respectively). Increase in serum insulin level correlated with decrease in fecal propionic acid by 5.3-folds (95% CI =  - 2.7,  - 0.15, p = 0.04). Increase in serum high sensitive C-reactive protein (hs-CRP) correlated with decrease in the percentage of fecal butyric acid by 25% (p = 0.04). Serum fasting blood sugar (FBS) and insulin showed a significant effect on fecal acetic acid (p = 0.009 and p = 0.01, respectively). Elevated serum FBS and insulin correlated with increase in fecal acetic acid by 2.8 and 8.9-folds (95%CI = 0.34, 1.9 and 1.2, 9.2), respectively. The LCD increased fecal SCFAs and a significant correlation was seen between serum IL-6 and fecal propionic acid level. More studies are needed to reach a concise correlation. Trial registration number: The trial was registered in Iranian ClinicalTrials.gov IRCT20200929048876N3.

Patterns of fatty acid usage in two nocturnal insectivores: the Mediterranean house gecko (Hemidactylus turcicus) and the Etruscan pygmy shrew (Suncus etruscus)

Dietary fatty acids (FAs) have been demonstrated to be differentially stored or used as a metabolic fuel, depending on carbon chain length or saturation level. However, intestinal absorption also differs among FAs, potentially biasing conclusions on functional differences and their subsequent implications. We tested dietary FA usage in a nocturnal insectivorous reptile and a nocturnal insectivorous mammal of similar size: the gecko Hemidactylus turcicus and the shrew Suncus etruscus. We compared the relative presence of 13C isotopes in breath and feces following ingestion of three isotopically enriched fatty acids: linoleic acid (a polyunsaturated FA), oleic acid (monounsaturated) and palmitic acid (saturated). Both species oxidized linoleic and oleic acids at much higher levels than palmitic acid. Egestion of palmitic acid in feces was much higher than that of linoleic and oleic acids. The major difference between geckos and shrews was that the latter digested fatty acids much faster, which was best explained by the difference in the metabolic rates of the species. Circadian differences were evident for gecko metabolic and FA oxidation rates, peaking at night; for shrews, peak oxidation was achieved faster at night but rates did not differ. Our study is among the first to integrate oxidation and absorption patterns, as well as metabolic rates and their rhythms, providing important insights into the utilization of different dietary FAs in different species.

Machine Learning Approaches for Predicting Fatty Acid Classes in Popular US Snacks Using NHANES Data

In the US, people frequently snack between meals, consuming calorie-dense foods including baked goods (cakes), sweets, and desserts (ice cream) high in lipids, salt, and sugar. Monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) are reasonably healthy; however, excessive consumption of food high in saturated fatty acid (SFA) has been related to an elevated risk of cardiovascular diseases. The National Health and Nutrition Survey (NHANES) uses a 24 h recall to collect information on people's food habits in the US. The complexity of the NHANES data necessitates using machine learning (ML) methods, a branch of data science that uses algorithms to collect large, unstructured, and structured data sets and identify correlations between the data variables. This study focused on determining the ability of ML regression models including artificial neural networks (ANNs), decision trees (DTs), k-nearest neighbors (KNNs), and support vector machines (SVMs) to assess the variability in total fat content concerning the classes (SFA, MUFA, and PUFA) of US-consumed snacks between 2017 and 2018. KNNs and DTs predicted SFA, MUFA, and PUFA with mean squared error (MSE) of 0.707, 0.489, 0.612, and 1.172, 0.846, 0.738, respectively. SVMs failed to predict the fatty acids accurately; however, ANNs performed satisfactorily. Using ensemble methods, DTs (10.635, 5.120, 7.075) showed higher error values for MSE than linear regression (LiR) (9.086, 3.698, 5.820) for SFA, MUFA, and PUFA prediction, respectively. R2 score ranged between -0.541 to 0.983 and 0.390 to 0.751 for models one and two, respectively. Extreme gradient boost (XGR), Light gradient boost (LightGBM), and random forest (RF) performed better than LiR, with RF having the lowest score for MSE in predicting all the fatty acid classes.

Longitudinal Associations of Healthy Dietary Pattern Scores with Coronary Artery Calcification and Pericardial Adiposity in United States Adults with and without Type 1 Diabetes

BACKGROUND

Pericardial adipose tissue volume (PAT) and coronary artery calcification (CAC) are prognostic indicators for future cardiovascular events; however, no studies have assessed the long-term associations of adherence to dietary patterns (DPs) with PAT and CAC in adults with and without type 1 diabetes (T1D).

OBJECTIVES

We investigated the longitudinal associations of the Mediterranean Diet (MedDiet) and Dietary Approaches to Stop Hypertension (DASH) diet with PAT and CAC progression in adults with and without T1D.

METHODS

The Coronary Artery Calcification in Type 1 Diabetes (CACTI) study is a population-based, prospective study of 652 T1D and 764 nondiabetic mellitus (nonDM) (19-56 y) participants that began in 2000-2002 with follow-up visits in 2003-2004 and 2006-2007. At each visit, food frequency questionnaires were collected and used to develop adherence scores for the MedDiet and DASH diets. PAT and CAC were measured at each visit using electron beam computed tomography. CAC progression was defined as a ≥2.5 mm square root-transformed volume. Mixed effect models were used to conduct statistical analyses.

RESULTS

Combined models found a significant-0.09 cm3 (95% CI: -0.14, -0.03; P = 0.0027) inverse association in PAT for every 1-point increase in the MedDiet score and a significant-0.26 cm3 (95% CI: -0.38, -0.14; P < 0.0001) inverse association in PAT for every 1-point increase in the DASH score. In combined models, the DPs were not significantly associated with lower odds of CAC progression; however, both DPs had significant interactions by diabetes status for CAC. Only the DASH diet was associated with lower odds of CAC progression in the nonDM group (OR: 0.96; 95% CI: 0.93, 0.99; P = 0.0224).

CONCLUSIONS

These data suggest that the DPs are associated with lower PAT, which may reduce future cardiovascular events. The DASH diet may be beneficial for lower odds of CAC progression in those without T1D.

Effect of diet on cardiovascular health-related circulating parameters in men and women athletes participating in a marathon race: A cross-sectional study

OBJECTIVES

The main objective of this study is to understand how diet affects performance and cardiovascular health in a group of women participating in a demanding aerobic race such as marathon, compared to men.

METHODS

Fifteen women participating in the Barcelona Marathon-2016 were recruited to participate in the study. A group of men (n = 15) that performed the same marathon race was selected. Anthropometric parameters and diet records were collected before the race. Circulating parameters were analyzed 24 h-pre-race, immediately after the race and 48 h-post-race. These included certain minerals, lipid profile, muscle damage, inflammatory and cardiovascular health markers.

RESULTS

Diets were very similar in the men and women, with inadequate amounts of carbohydrates and proteins for endurance events. Creatine kinase (CK; a muscle damage marker) and C-reactive protein (CRP; a marker of inflammation) remained elevated 48 h post-race in all participants, but was significant in women (641 vs. 143 U/L for CK and 5.8 vs. 0.7 mg/dL for CRP). Cardiac markers (high sensitivity troponin T (Hs-TnT), suppression of tumorigenicity and N-terminal pro B-type natriuretic peptide) increased post-race and returned to pre-race values after 48 h in men and women. In particular, Hs-TnT (marker of myocyte stress) increased from 2.2 to 62.5 ng/L post-race in women and from 3.1 to 52.9 ng/L in men. Finally, circulating lipid parameters were at borderline unhealthy levels in both sexes.

CONCLUSION

Structural and functional cardiac advantages that women display compared to men in aerobic efforts are not manifested when diet is not adequately designed.

The Effect of Mediterranean Diet on Body Composition, Inflammatory Factors, and Nutritional Status in Patients with Cachexia Induced by Colorectal Cancer: A Randomized Clinical Trial

BACKGROUND

Along with high calorie and high protein diet, a new comprehensive dietary approach is needed to control cachexia caused by cancer and its related outcomes. This study was done to evaluate the effect of a Mediterranean diet on body composition, nutritional status, and inflammatory markers among cancer cachexia patients.

METHODS

In this randomized clinical trial, 46 patients with colorectal cancer-induced cachexia were included. After randomization, 23 patients were allocated to the intervention group (Mediterranean diet) and 23 to the control group (nutritional counseling for weight gain and prevention of weight loss in cancer patients). The primary outcome including muscle health, nutritional status, and inflammatory markers along with secondary outcomes such as quality of life, and serum proteins were evaluated at the start and the eighth week of the study. Statistical analysis was performed according to the intention-to-treat concept. To compare changes in dependent variables between the 2 groups, analysis of covariance (ANCOVA) was performed.

RESULTS

After adjustment for the baseline values, age, sex, and supplements use, in the Mediterranean diet group mean of weight (P < .001), lean body mass (P = .001), fat mass (P = .002), and muscle strength (P < .001) were significantly increased compared to the control group. Regarding inflammatory markers, the mean serum level of tumor necrosis factor-alpha (TNF-α) (P < .001), high sensitive-C-reactive protein (hs-CRP) (P = .01) and Interleukin 6 (IL-6) (P < .001) were significantly improved in the Mediterranean diet group. Moreover, in the Mediterranean diet group, the score for global health status (P = .02) and physical performance score (P < .001) were significantly increased.

CONCLUSION

It appears that the implementation of the Mediterranean diet might be a strategy to improve nutritional status, quality of life, inflammatory markers, and body composition in patients with colorectal cancer cachexia.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials (www.irct.ir); ID: IRCT20211027052884N1.

Effect of Consuming Beef with Varying Fatty Acid Compositions as a Major Source of Protein in Volunteers under a Personalized Nutritional Program

Beef is an excellent source of nutrients; unfortunately, most nutritional recommendations suggest limiting or even avoiding it. Studies have shown that the fatty acid composition of meat influences weight loss. This randomized controlled clinical trial evaluated the anthropometric and serum lipid changes after a food intervention that included frequent beef consumption (120 g consumed four days/week for four weeks). Volunteers were randomly assigned to the commercial or Wagyu-Cross beef groups, with the latter beef possessing higher fat and MUFA contents. Both groups exhibited reductions in body measurements and lipid profiles; however, the Wagyu-Cross group exhibited greater changes in weight (-3.75 vs. -2.90 kg) and BMI (-1.49 vs. -1.03) than the commercial group, without a significant difference between them. No significant group differences in lipid profiles were observed; however, the Wagyu-Cross group exhibited a more favorable change in decreasing the TC concentration (-7.00 mg/dL) and LDL-C concentration (-12.5 mg/dL). We suggest that high MUFA beef could be included in weight-loss programs since it does not affect weight loss and hasn't a negative influence on lipid metabolism.

Metabolic Responses to Eight Weeks of Consuming Cottonseed Oil v. Olive Oil in Adults with Dyslipidemia, a Randomized Trial

BACKGROUND

Differences in metabolic responses between diets rich in monounsaturated (MUFA) and polyunsaturated fats (PUFA) could affect energy balance and weight maintenance. The present study was a secondary analysis to investigate 8-week diet interventions rich in either PUFA (cottonseed oil (CSO)) or MUFA (olive oil (OO)) on metabolic responses in adults with dyslipidemia.

METHODS

Forty-one adults with dyslipidemia completed this randomized trial consisting of an 8-week partial-outpatient feeding trial. Provided foods accounted for ~60% of their daily energy needs, with ~30% of energy needs provided by CSO (n=20) or OO (n=21). At pre- and post-diet intervention visits, participants consumed a high saturated fat (SFA) meal (35% daily energy needs, 47.9% from SFA), and fasting and 3.5h postprandial indirect calorimetry was used to measure energy expenditure (EE) and substrate oxidation.

RESULTS

No changes were observed in fasting measures. The OO group had greater increases in postprandial EE (p=0.002); however, there were no differences in substrate oxidation between groups. A lack of metabolic flexibility was found in both groups, which was partially explained by changes in insulin sensitivity (homeostasis model assessment of insulin resistance (HOMA-IR)).

CONCLUSIONS

The results of the present study show OO, but not CSO, diet enrichment improves EE following the occasional high SFA meal, which may improve weight maintenance over time. Registered at clinicaltrials.gov (NCT04397055). This article is protected by copyright. All rights reserved.

Human body weight, nutrients, and foods: a scoping review

Background

The aim of this article (scoping review) is to elucidate the current knowledge for the potential role of body weight for setting and updating Dietary Reference Values (DRVs) and Food-Based Dietary Guidelines (FBDGs). The following research questions were formulated:What is known about the association between intakes of specific nutrient and/or foods (exposure/intervention) and body weight (outcome) in the general population?What is known about the association between body weight (exposure) and intakes of specific nutrient and/or foods (outcomes)?Is there any evidence suggesting specific effects of foods or nutrients on body weight independent of caloric content?

Methods

To identify potentially relevant articles, PubMed was searched from January 1, 2011 to June 9, 2021. The search strategy was drafted by the NNR2022 Committee. The final results were exported into EndNote. Systematic reviews (SRs), scoping reviews (ScRs), reviews, and meta-analyses (MAs) on the topic 'Body weight' published between January 1, 2011 and June 9, 2021, including human participants from the general population, in English or Scandinavian language (Norwegian, Swedish, or Danish), were considered eligible.

Main findings

First, the overall body of evidence based on findings from SRs and MAs of observational and clinical studies indicates that changes in intakes of specific nutrients (sugar, fiber, and fat) and/or foods (sugar sweetened beverages, fiber rich food, and vegetables) are associated with modest or small short-term changes (0.3-1.3 kg) in body weight in the general population (with or without obesity/overweight), while long-term studies are generally lacking. Second, no study in our search assessed any association between body weight (exposure) and intakes of specific nutrients or foods (outcomes). Third, limited evidence suggests, but does not prove, that some foods or nutrients may have specific effects on body weight or body weight measures independent of caloric content (e.g. nuts and dairy). These findings may inform the setting and updating of DRVs and FBDGs in NNR2022.

Increased Consumption of Unsaturated Fatty Acids Improves Body Composition in a Hypercholesterolemic Chinese Population

While an increase in fat intake and the resulting excess calorie intake are implicated in weight gain, different fat types exert variable effects on body composition, with unsaturated fats showing favorable effects on body composition in Western population. Whether and to what extent these associations apply to Asian population have not been established. We investigated the effects of two separate Asian-based oil blends, rich in unsaturated fats, made from refined rice bran, sesame, and flaxseed oils, in comparison with refined olive oil, on body composition using dual-energy X-ray absorptiometry (DXA), from an 8-week, parallel design, randomized trial in 66 men (58.7 ± 5.71 years old, 23.0 ± 2.38 kg/m²) and 69 postmenopausal women (59.1 ± 5.34 years old, 21.7 ± 2.52 kg/m²), with borderline hypercholesterolemia. Despite increases in mean daily intakes of total energy (approximately +400 kcal/day, female, and approximately +240 kcal/day, male), as well as increases in percentage of calories from fats and proteins and decreases in percentage of calories from carbohydrates during the dietary intervention period, there were no significant changes in total body fat mass in both genders and also in all treatment groups. While total body weight increased slightly (0.36 ± 0.12 kg, p = 0.005) in women during intervention, this was mainly due to gain in lean mass (0.38 ± 0.081 kg, p < 0.0001). Correspondingly, there were reductions in total body fat (%), android fat (%), and gynoid fat (%) in women. No significant differences between the 3 intervention oil types were found in any of the measured parameters in either gender. Increasing relative intakes of unsaturated fats may prevent fat mass gain and circumvent muscle mass loss associated with menopause in older Asian women. Long-term studies are needed to confirm findings. This study had been registered on clinicaltrials.gov (Identifier No.: NCT03964857, https://www.clinicaltrials.gov/ct2/show/NCT03964857).

ChREBP-driven DNL and PNPLA3 Expression Induced by Liquid Fructose are Essential in the Production of Fatty Liver and Hypertriglyceridemia in a High-Fat Diet-Fed Rat Model

SCOPE

The aim of this study is to delineate the contribution of dietary saturated fatty acids (FA) versus liquid fructose to fatty liver and hypertriglyceridemia.

METHODS AND RESULTS

Three groups of female rats are maintained for 3 months in standard chow (CT); High-fat diet (46.9% of fat-derived calories, rich in palmitic and stearic FA, HFD); and HFD with 10% w/v fructose in drinking water (HFHFr). Zoometric parameters, plasma biochemistry, and liver Oil-Red O (ORO) staining, lipidomics, and expression of proteins involved in FA metabolism are analyzed. Both diets increase ingested calories without modifying body weight. Only the HFHFr diet increases liver triglycerides (x11.0), with hypertriglyceridemia (x1.7) and reduces FA β-oxidation (x0.7), and increases liver FA markers of DNL (de novo lipogenesis). Whereas HFD livers show a high content of ceramides, HFHFr samples show unchanged ceramides, and an increase in diacylglycerols. Only the HFHFr diet leads to a marked increase in the expression of enzymes involved in DNL and triglyceride metabolism, such as carbohydrate response element binding protein β (ChREBPβ, x3.2), a transcription factor that regulates DNL, and patatin-like phospholipase domain-containing 3 (PNPLA3, x2.6), a lipase that mobilizes stored triglycerides for VLDL secretion.

CONCLUSION

The addition of liquid-fructose to dietary FA is determinant in liver steatosis and hypertriglyceridemia production, through increased DNL and PNPLA3 expression, and reduced FA catabolism.

Changes in body weight in response to pecan-enriched diets with and without substitution instructions: a randomised, controlled trial

Substantial evidence suggests that regular tree nut consumption does not lead to changes in body weight (BW). However, these studies used a variety of dietary substitution instructions which may confound the interpretation of prior BW outcomes. The purpose of the present study was to examine the impact of daily pecan consumption, with or without isocaloric substitution instructions, on BW and composition. This was an 8-week randomised, controlled trial with three treatments: a nut-free control group (n 32) and two pecan groups. ADD (n 30) consumed pecans (68 g/d) as part of a free-living diet, and SUB (n 31) substituted the pecans (68 g/d) for isocaloric foods from their habitual diet. BW and total body fat percentage (BF) were measured, and theoretical changes in these outcomes if pecans were consumed without compensation were determined. BW increased in all groups across the intervention, and there was a trend (P = 0⋅09) for an increase in ADD (1⋅1 ± 0⋅2 kg) and SUB (0⋅9 ± 0⋅3 kg) compared to control (0⋅3 ± 0⋅2 kg). In addition, there was increased BF in SUB (1⋅0 ± 0⋅3 %; P = 0⋅005) but not ADD (0⋅1 ± 0⋅2 %) or control (−0⋅2 ± 0⋅3 %) There was a large difference in the actual v. theoretical change in BW regardless of pecan treatment (actual: 1⋅1 ± 0⋅2 and 0⋅9 ± 0⋅3 v. theoretical: 3⋅3 ± 0⋅0 and 3⋅2 ± 0⋅0 kg in ADD and SUB, respectively; P < 0⋅001). Furthermore, there was a difference in actual v. theoretical change in BF in ADD (0⋅1 ± 0⋅2 v. 1⋅2 ± 0⋅1 %; P = 0⋅002) but not SUB or control. In conclusion, daily pecan consumption for 8 weeks did not result in significant weight gain, regardless of dietary substitution instructions.

Fatty Acid Composition of Grain- and Grass-Fed Beef and Their Nutritional Value and Health Implication

Beef contains functional fatty acids such as conjugated linoleic acid and long-chain fatty acids. This review summarizes results from studies comparing the fatty acid composition of beef from cattle fed either grass or grain-based feed. Since functional lipid components are contributed through dietary consumption of beef, the fatty acid composition is reported on mg/100 g of meat basis rather than on a percentage of total fat basis. Beef from grass-fed contains lesser total fat than that from grain-fed in all breeds of cattle. Reduced total fat content also influences the fatty acid composition of beef. A 100 g beef meat from grass-fed cattle contained 2,773 mg less total saturated fatty acids (SFA) than that from the same amount of grain-fed. Grass-fed also showed a more favorable SFA lipid profile containing less cholesterol-raising fatty acids (C12:0 to C16:0) but contained a lesser amount of cholesterol-lowering C18:0 than grain-fed beef. In terms of essential fatty acids, grass-fed beef showed greater levels of trans-vaccenic acid and long-chain n-3 polyunsaturated fatty acids (PUFA; EPA, DPA, DHA) than grain-fed beef. Grass-fed beef also contains an increased level of total n-3 PUFA which reduced the n-6 to n-3 ratio thus can offer more health benefits than grain-fed. The findings signify that grass-fed beef could exert protective effects against a number of diseases ranging from cancer to cardiovascular disease (CVD) as evidenced by the increased functional omega-3 PUFA and decreased undesirable SFA. Although grain-fed beef showed lesser EPA, DPA, and DHA, consumers should be aware that greater portions of grain-fed beef could also achieve a similar dietary intake of long-chain omega-3 fatty acids. Noteworthy, grain-fed beef contained higher total monounsaturated fatty acid that have beneficial roles in the amelioration of CVD risks than grass-fed beef. In Hanwoo beef, grain-fed showed higher EPA and DHA than grass-fed beef.

MUFA in metabolic syndrome and associated risk factors: is MUFA the opposite side of the PUFA coin?

Omega-9 fatty acids represent some of the main mono-unsaturated fatty acids (MUFA) found in plant and animal sources. They can be synthesized endogenously in the human body, but they do not fully provide all the body's requirements. Consequently, they are considered as partially essential fatty acids. MUFA represent a healthier alternative to saturated animal fats and have several health benefits, including the prevention of metabolic syndrome (MetS) and its complications. This review concentrates on the major MUFA pharmacological activities in the context of MetS management, including alleviating cardiovascular disease (CVD) and dyslipidemia, central obesity, non-alcoholic fatty liver disease (NAFLD), and type 2 diabetes mellitus (T2DM). The beneficial effects of MUFA for CVD were found to be consistent with those of polyunsaturated fatty acids (PUFA) for the alleviation of systolic and diastolic blood pressure and high low density lipoprotein cholesterol (LDLc) and triacylglcerol (TAG) levels, albeit MUFA had a more favorable effect on decreasing night systolic blood pressure (SBP). To reduce the obesity profile, the use of MUFA was found to induce a higher oxidation rate with a higher energy expenditure, compared with PUFA. For NAFLD, PUFA was found to be a better potential drug candidate for the improvement of liver steatosis in children than MUFA. Any advantageous outcomes from using MUFA for diabetes and insulin resistance (IR) compared to using PUFA were found to be either non-significant or resulted from a small number of meta-analyses. Such an increase in the number of studies of the mechanisms of action require more clinical and epidemiological studies to confirm the beneficial outcomes, especially over a long-term treatment period.

Pecan-enriched diets increase energy expenditure and fat oxidation in adults at-risk for cardiovascular disease in a randomised, controlled trial

BACKGROUND

Research indicates that diets enriched with unsaturated fatty acids improve energy metabolism, although studies on tree nuts, which are a rich source of those fats, are limited. The present study aimed to examine the impact of daily pecan consumption for 8 weeks on energy metabolism in adults with hypercholesterolaemia or at higher risk for cardiovascular disease (CVD) (body mass index ≥ 28 kg m^-2 ).

METHODS

For this randomised, controlled trial, 56 sedentary adults were randomised into one of three treatments for an 8-week intervention: two pecan groups and a nut-free control group (n = 18). The ADD group (n = 16) consumed pecans as part of a free-living diet, whereas the SUB group (n = 18) substituted the pecans for isocaloric foods from their habitual diet. At baseline and 8 weeks, a high saturated fat meal was consumed along with indirect calorimetry measurements at fasting and for 4 h postprandially to determine changes in resting metabolic rate (RMR), diet induced thermogenesis (DIT) and substrate utilisation (primary outcomes). Forty-seven participants completed the trial and were included in analyses.

RESULTS

In the SUB group, there was an increase in fasting RMR (1607 ± 117 to 1701 ± 114 kcal day^-1 ; p = 0.01) and fasting fat oxidation (0.83 ± 0.08 to 0.99 ± 0.08 g/15 min; p = 0.009) and a decrease in fasting respiratory exchange ratio (0.85 ± 0.01 to 0.83 ± 0.01; p = 0.05) from pre- to post-intervention. In the ADD group, there was an increase in postprandial DIT (p < 0.001). There were no changes within the control group or between groups for any outcome measure.

CONCLUSIONS

Daily consumption of pecans may increase select measures of energy expenditure and fat oxidation in adults at-risk for CVD.

The effects of dietary saturated fat source on weight gain and adiposity are influenced by both sex and total dietary lipid intake in zebrafish

The effects of saturated fat intake on obesity and cardiovascular health remain inconclusive, likely due in part to their varied nature and interactions with other nutrients. Investigating the synergistic effects of different saturated fat sources with other dietary lipid components will help establish more accurate nutritional guidelines for dietary fat intake. Over the past two decades, zebrafish (Danio rerio) have been established as an attractive model system to address questions regarding contributions of dietary lipid intake to diet-induced obesity in humans. The goal of the present study was to assess interactions of three different saturated fat sources (milk fat, palm oil, and coconut oil) with sex and total dietary lipid intake on weight gain and body composition in adult zebrafish. Larvae were raised on live feeds until 28 days post fertilization, and then fed a formulated maintenance diet until three months of age. An eight-week feeding trial was then initiated, in which zebrafish were fed nine experimental low- and high-fat diets varying in saturated fatty acid and long-chain polyunsaturated fatty acid content, in addition to a low-fat and high-fat control diet. At termination of the feeding trial, each treatment was evaluated according to body mass, moisture content, and adiposity. Sex and diet significantly interacted in their effects on body mass (P = 0.026), moisture content (P = 0.044), and adiposity (P = 0.035). The influence of saturated fat source on body mass was observed to be dependent on intake of total dietary lipid. In females, all three saturated fat sources had similar effects on adiposity. From these observations, we hypothesize that impacts of saturated fat intake on energy allocation and obesity-related phenotypes are influenced by both sex and intake of other dietary lipid components. Our results suggest that current nutritional guidelines for saturated fat intake may need to be re-evaluated and take sex-specific recommendations into consideration.

The effect of a Mediterranean diet vs. a low-fat diet on non-alcoholic fatty liver disease in children: a randomized trial

Non-alcoholic fatty liver disease (NAFLD) is becoming ever more common in children, due to the increasing global prevalence of obesity. The first-line treatment consists of weight loss through a combination of a healthy diet and exercise. The objective of this study was to determine the effects of a Mediterranean Diet or a low-fat diet on reducing hepatic steatosis and insulin resistance in children with NAFLD. This 12-week randomised clinical trial was conducted with children aged 9-17 years diagnosed with NAFLD and randomised into either a Mediterranean Diet or a low-fat diet group. By the end of the study, hepatic steatosis had decreased significantly in both groups (p < 0.001). Liver enzymes also improved significantly, while significant decreases were observed in insulin resistance in both groups, although this decrease was greater in the Mediterranean Diet group (p = 0.010). This study demonstrated that a decrease in hepatic steatosis and an improvement in insulin sensitivity can be achieved with both a Mediterranean Diet and a low-fat diet over 12 weeks, with no significant decrease in the energy required for growth, in children with NAFLD.

Adherence to the Mediterranean diet and body composition of breast-feeding mothers: the potential role of unsaturated fatty acids

A paucity of evidence is available regarding the impact of diet's quality during pregnancy and lactation on the body composition of breast-feeding mothers. The purpose of the present study was to evaluate the association between maternal degree of adherence to the Mediterranean diet (MD) and body composition measures specifically those relating to body fat, in the lactation period. A cross-sectional study on healthy mothers of full-term babies has been conducted. At 30 ± 10 d after delivery, anthropometric measurements and body composition were assessed. A food frequency questionnaire was performed to compute the Italian Mediterranean Index (IMI) score as an index of adherence to the MD. Data related to pregnancy such as pre-pregnancy weight, gestational weight gain and morbidities were also collected. The 147 mothers included were categorised in IMI-1 (IMI score < 5; n 92) and IMI-2 (IMI score ≥ 5; n 55) groups. IMI-2 mothers showed higher daily energy, total carbohydrates, starch and fibre intakes than IMI-1. The dietary habits of IMI-2 mothers reflect the typical characteristics of MD: they consumed higher quantities of proteins and lipids of vegetal origin, higher amounts of monounsaturated and polyunsaturated fatty acids (PUFAs) and lower saturated to PUFAs ratio. The IMI-2 group showed lower absolute fat mass and fat mass index compared to IMI-1 [(20⋅2 ± 5⋅9) v. (22⋅9 ± 8⋅4) kg; P 0⋅036 and (7⋅5 ± 2⋅2) v. (8⋅5 ± 3⋅1) kg/m²; P 0⋅036, respectively], whereas body weight [(61⋅1 ± 8⋅0) v. (63⋅3 ± 9⋅2) kg] and body mass index [(22⋅4 ± 2⋅6) v. (23⋅3 ± 3⋅5) kg/m²] were similar. The degree of adherence to the MD during pregnancy and lactation is positively associated with lower maternal fat deposition in the breast-feeding period. The higher quality of dietary lipids, probably in synergy with the assumption of starchy carbohydrates and fibre, could influence maternal body fat.

Docosahexaenoic Acid Suppresses Expression of Adipogenic Tetranectin through Sterol Regulatory Element-Binding Protein and Forkhead Box O Protein in Pigs

Tetranectin (TN), a plasminogen-binding protein originally involved in fibrinolysis and bone formation, was later identified as a secreted adipokine from human and rat adipocytes and positively correlated with adipogenesis and lipid metabolism in adipocytes. To elucidate the nutritional regulation of adipogenic TN from diets containing different sources of fatty acids (saturated, n-6, n-3) in adipocytes, we cloned the coding region of porcine TN from a cDNA library and analyzed tissue expressions in weaned piglets fed with 2% soybean oil (SB, enriched in n-6 fatty acids), docosahexaenoic acid oil (DHA, an n-3 fatty acid) or beef tallow (BT, enriched in saturated and n-9 fatty acids) for 30 d. Compared with tissues in the BT- or SB-fed group, expression of TN was reduced in the adipose, liver and lung tissues from the DHA-fed group, accompanied with lowered plasma levels of triglycerides and cholesterols. This in vivo reduction was also confirmed in porcine primary differentiated adipocytes supplemented with DHA in vitro. Then, promoter analysis was performed. A 1956-bp putative porcine TN promoter was cloned and transcription binding sites for sterol regulatory-element binding protein (SREBP)-1c or forkhead box O proteins (FoxO) were predicted on the TN promoter. Mutating binding sites on porcine TN promoters showed that transcriptional suppression of TN by DHA on promoter activity was dependent on specific response elements for SREBP-1c or FoxO. The inhibited luciferase promoter activity by DHA on the TN promoter coincides with reduced gene expression of TN, SREBP-1c, and FoxO1 in human embryonic kidney HEK293T cells supplemented with DHA. To conclude, our current study demonstrated that the adipogenic TN was negatively regulated by nutritional modulation of DHA both in pigs in vivo and in humans/pigs in vitro. The transcriptional suppression by DHA on TN expression was partly through SREBP-1c or FoxO. Therefore, down-regulation of adipogenic tetranectin associated with fibrinolysis and adipogenesis may contribute to the beneficial effects of DHA on ameliorating obesity-induced metabolic syndromes such as atherosclerosis and adipose dysfunctions.

The effect of extra virgin olive oil on anthropometric indices, lipid profile, and markers of oxidative stress and inflammation in patients with depression, a double-blind randomised controlled trial

BACKGROUND

Epidemiological evidence suggests a mutual association between depression and obesity and also an anti-obesity effect for olive oil. We examined the effect of extra virgin olive oil (EVOO) on weight, waist circumference, and a number of cardiovascular risk factors in patients with depression.

METHODS

The randomised double-blind controlled trial was conducted on 62 patients with depression. Patients were randomly allocated to EVOO and sunflower oil groups (n = 31 for each) that consumed 25 mL/day of the corresponding oils for 52 days. An isocaloric diet was prescribed to each patient according to his/her previous energy intake with considering the energy provided by the administered oils. Weight, body mass index (BMI), waist circumference, blood lipids, malondialdehyde, and hs-C reactive protein (CRP) analysis were performed using the intention-to-treat approach.

RESULTS

BMI was significantly decreased in sunflower oil group (-0.20 ± 0.53 kg/m² , P = .047) and waist circumference was significantly decreased in EVOO group (-2.15 ± 2.09 cm, P < .001); however, only reduction of waist circumference was significantly different between groups (P < .001). High-density lipoprotein (HDL) cholesterol was significantly increased in EVOO group (3.02 ± 6.79 mg/dL, P = .03), without showing a significant between-group difference. Other lipids, malondialdehyde, and hs-CRP did not change.

CONCLUSION

Overall, the results suggest that both EVOO and sunflower oil may benefit overweight patients with depression, as they respectively decreased waist circumference and BMI without need for administration of a low-calorie diet.

Metabolic Characterization of Meat, Fish, and Soda Intake in Males: Secondary Results from a Randomized Inpatient Pilot Study

OBJECTIVE

This study aimed to evaluate whether a 12-week, weight-maintaining, macronutrient-stable dietary intervention that varies only by meat, fish, or soda consumption alters 24-hour energy expenditure (24hrEE) and substrate oxidation.

METHODS

Healthy males were recruited to participate in a 12-week inpatient study and were randomized to a weight-maintaining dietary intervention that contained varying combinations of meat (0% or 19%), fish (0% or 6%), or soda (0% or 14%) in a factorial design. Macronutrient composition across dietary intervention groups was as follows: 50% of energy from carbohydrates, 30% of energy from fat, and 20% of energy from protein. Whole-room indirect calorimetry at baseline and week 12 were used to measure 24hrEE and substrate oxidation.

RESULTS

Twenty-six males (mean [SEM], age: 46.6 [10.4] years; BMI: 26.9 [4.1] kg/m2 ) completed all measurements. Fish consumption resulted in higher 24hrEE by 126 (55) kcal/d compared with no fish consumption (P = 0.03), whereas 24hrEE for soda consumption was 132 (56) kcal/d (P = 0.03) lower. Approximately 80% of the decrease in 24hrEE with soda consumption was due to lower awake-inactive energy expenditure (EE; P = 0.001). No specific EE component accounted for the differences observed with fish consumption.

CONCLUSIONS

The data indicate that dietary sources of protein and carbohydrates appear to influence 24hrEE and inactive EE.

Intake of Nuts or Nut Products Does Not Lead to Weight Gain, Independent of Dietary Substitution Instructions: A Systematic Review and Meta-Analysis of Randomized Trials

Several clinical interventions report that consuming nuts will not cause weight gain. However, it is unclear if the type of instructions provided for how to incorporate nuts into the diet impacts weight outcomes. We performed a systematic review and meta-analysis of published nut-feeding trials with and without dietary substitution instructions to determine if there are changes in body weight (BW) or composition. PubMed and Web of Science were searched through 31 December 2019 for clinical trials involving the daily consumption of nuts or nut-based snacks/meals by adults (≥18 y) for >3 wk that reported BW, BMI, waist circumference (WC), or total body fat percentage (BF%). Each study was categorized by whether or not it contained dietary substitution instructions. Within these 2 categories, an aggregated mean effect size and 95% CI was produced using a fixed-effects model. Quality of studies was assessed through the Cochrane risk-of-bias tool. Fifty-five studies were included in the meta-analysis. In studies without dietary substitution instructions, there was no change in BW [standardized mean difference (SMD): 0.01 kg; 95% CI: -0.07, 0.08; I2 = 0%] or BF% (SMD: -0.05%; 95% CI: -0.19, 0.09; I2 = 0%). In studies with dietary substitution instructions, there was no change in BW (SMD: -0.01 kg; 95% CI: -0.11, 0.09; I2 = 0%); however, there was a significant decrease in BF% (SMD: -0.32%; 95% CI: -0.61%, -0.03%; I2 = 35.4%; P < 0.05). There was no change in BMI or WC for either category of studies. Nut-enriched diet interventions did not result in changes in BW, BMI, or WC in studies either with or without substitution instructions. Slight decreases in BF% may occur if substitution instructions are used, but more research is needed. Limitations included varying methodologies between included studies and the frequency of unreported outcome variables in excluded studies.

Polyunsaturated fatty acids as modulators of fat mass and lean mass in human body composition regulation and cardiometabolic health

It is now recognized that the amount and type of dietary fat consumed play an important role in metabolic health. In humans, high intake of polyunsaturated fatty acids (PUFAs) has been associated with reductions in cardiovascular disease risk, improvements in glucose homeostasis, and changes in body composition that involve reductions in central adiposity and, more recently, increases in lean body mass. There is also emerging evidence, which suggests that high intakes of the plant-based essential fatty acids (ePUFAs)-n-6 linoleic acid (LA) and n-3 α-linolenic acid (ALA)-have a greater impact on body composition (fat mass and lean mass) and on glucose homeostasis than the marine-derived long-chain n-3 PUFA-eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). In addition, high intake of both ePUFAs (LA and ALA) may also have anti-inflammatory effects in humans. The purpose of this review is to highlight the emerging evidence, from both epidemiological prospective studies and clinical intervention trials, of a role for PUFA, in particular ePUFA, in the long-term regulation of body weight and body composition, and their impact on cardiometabolic health. It also discusses current notions about the mechanisms by which PUFAs modulate fat mass and lean mass through altered control of energy intake, thermogenesis, or lean-fat partitioning.

Obesity-Related Changes in Human Plasma Lipidome Determined by the Lipidyzer Platform

Obesity is an increasing public health concern both in the developed and developing countries. Previous studies have demonstrated that considerable alterations in lipid metabolism and consequently marked changes in lipid profile are associated with the onset and progression of obesity-related complications. To characterize the full spectrum of obesity-induced changes in lipid metabolism, direct infusion tandem mass spectrometry analysis is the most promising approach. To better understand which of the many lipid species are the most strongly associated with obesity, the aim of our work was to measure and profile plasma lipids in normal (n = 57), overweight (n = 31), and obese (n = 48) individuals randomly selected from samples of Hungarian general and Roma populations by using the targeted quantitative lipidomics platform, the Lipidyzer. Principal component and stepwise regression analyses were used to identify the most significant clusters and species of lipids by increasing body mass index (BMI). From the 18 clusters identified four key lipid species (PE P-16:0/20:3, TG 20:4_33:1, TG 22:6_36:4, TG 18:3_33:0) showed a strong significant positive and three others (Hex-Cer 18:1;O2/22:0, LPC 18:2, PC 18:1_18:1) significant negative association with BMI. Compared to individual lipid species alone, the lipid species ratio (LSR) we introduced showed an extremely strong, at least 9 orders of magnitude stronger, association with BMI. The LSR can be used as a sensitive and predictive indicator to monitor obesity-related alterations in human plasma and control the effectiveness of treatment of obesity associated non-communicable diseases.

Gut microbiome and Mediterranean diet in the context of obesity. Current knowledge, perspectives and potential therapeutic targets

Mediterranean Diet has been recognized as one of the healthiest and sustainable dietary patterns worldwide, based on the food habits of people living in the Mediterranean region. It is focused on a plant-based cuisine combining local agricultural products and moderate intake of fish. As eating habits seem to exert a major impact on the composition of gut microbiota, numerous studies show that an adherence to the Mediterranean diet positively influences the microbiome ecosystem network. This has a profound effect on multiple host metabolic pathways and plays a major role in immune and metabolic homeostasis. Among metabolic disorders, obesity represents a major health issue where Mediterranean Dietary regime could possibly slowdown its spread. The aim of this review is to emphasize the interaction between diet and gut microbiota and the potential beneficial effects of Mediterranean diet on metabolic disorders like obesity, which is responsible for the development of many noncommunicable diseases.

Effects of short-term methionine and cysteine restriction and enrichment with polyunsaturated fatty acids on oral glucose tolerance, plasma amino acids, fatty acids, lactate and pyruvate: results from a pilot study

Objective

In this 7-day pilot study we randomized healthy, normal-weight men and women to either a dietary intervention with methionine and cysteine restriction enriched in PUFA (Met/Cys_low + PUFA, n = 7) or with high contents of methionine, cysteine and SFA (Met/Cys_high + SFA, n = 7). The objective was to describe the short-term responses in oral glucose tolerance, amino acid profile, total fatty acid profile, pyruvate and lactate following a Met/Cys_low + PUFA diet vs. Met/Cys_high + SFA.

Results

The diet groups consisted of five women and two men, aged 20–38 years. After the 7-d intervention median pre- and post-oral glucose tolerance test (OGTT) glucose concentrations were 5 mmol/L and 4 mmol/L respectively in the Met/Cys_low + PUFA group. In the Met/Cys_high + SFA group, median pre- and post-OGTT glucose concentrations were 4.8 mmol/L and 4.65 mmol/L after the 7-d intervention. The responses in the amino acid profiles were similar in both groups during the intervention with the exception of serine. Fatty acids decreased from baseline to day 7 in both groups. Plasma lactate and pyruvate were similar for both groups with an increase to day 3 before approaching baseline values at day 7.

Trial registration

ClinicalTrials.gov: NCT02647970, registration date: January 6^th 2016.

Hypothalamic Renin-Angiotensin System and Lipid Metabolism: Effects of Virgin Olive Oil versus Butter in the Diet

The brain renin-angiotensin system (RAS) has been recently involved in the homeostatic regulation of energy. Our goal was to analyse the influence of a diet rich in saturated fatty acids (butter) against one enriched in monounsaturated fatty acids (olive oil) on hypothalamic RAS, and their relationship with the metabolism of fatty acids. Increases in body weight and visceral fat, together with an increase in aminopeptidase A expression and reductions in AngII and AngIV were observed in the hypothalamus of animals fed with the butter diet. In this group, a marked reduction in the expression of genes related to lipid metabolism (LPL, CD36, and CPT-1) was observed in liver and muscle. No changes were found in terms of body weight, total visceral fat and the expression of hepatic genes related to fatty acid metabolism in the olive oil diet. The expressions of LPL and CD36 were reduced in the muscles, although the decrease was lower than in the butter diet. At the same time, the fasting levels of leptin were reduced, no changes were observed in the hypothalamic expression of aminopeptidase A and decreases were noted in the levels of AngII, AngIV and AngIII. These results support that the type of dietary fat is able to modify the hypothalamic profile of RAS and the body energy balance, related to changes in lipid metabolism.

Table olives and health: a review

Table olives, a product of olive tree (Olea europaea L.), is an important fermented product of the Mediterranean Diet. Agronomical factors, particularly the cultivar, the ripening stage and the processing method employed are the main factors influencing the nutritional and non-nutritional composition of table olives and their organoleptic properties. The important nutritional value of this product is due to its richness in monounsaturated fat (MUFA), mainly oleic acid, fibre and vitamin E together with the presence of several phytochemicals. Among these, hydroxytyrosol (HT) is the major phenolic compound present in all types of table olives. There is a scarcity of in vitro, in vivo and human studies of table olives. This review focused comprehensively on the nutrients and bioactive compound content as well as the health benefits assigned to table olives. The possible health benefits associated with their consumption are thought to be primarily related to effects of MUFA on cardiovascular health, the antioxidant (AO) capacity of vitamin E and its role in protecting the body from oxidative damage and the anti-inflammatory and AO activities of HT. The influence of multiple factors on composition of the end product and the potential innovation in the production of table olives through the reduction of its final salt content was also discussed.

A review on differential effects of dietary fatty acids on weight, appetite and energy expenditure

The association between weight and chronic diseases is well defined. The quality and quantity of dietary fatty acids is an important external factor and appetite and energy expenditure, are important internal factors in determining body weight. On the other hand, dietary fatty acids composition can modulate appetite and energy metabolism, but not all fats are equal in producing metabolic responses.Given the accumulating evidence for differential effects of various dietary fatty acids, one important area of investigation is to scrutinize their roles in weight, appetite and energy expenditure modulation. There is substantial evidence to suggest that saturated fatty acids have a greater effect on appetite control, although in the long run may result in more weight gain than unsaturated fatty acids due to a weaker stimulation of energy expenditure. In contrast, mono-unsaturated fats do not have much effects on appetite control, but they can be beneficial in weight control over the long term due to stimulatory effects on energy expenditure. Interestingly, in case of poly unsaturated fats, including n-3 and n-6, their effect on increasing energy expenditure is aligned, but they act differently in controlling weight and appetite.

Concurrent training and Eri silkworm pupae ingestion improve resting and exercise fat oxidation and energy expenditure in obese adults

A randomized control trial was conducted to investigate the effects of combined concurrent training and Eri silkworm pupae ingestion on resting and exercise fat oxidation (FAO), as well as energy expenditure, and cardiometabolic risk markers in obese adults. Thirty-six sedentary, obese participants were divided into three groups: (1) placebo control group (CON, n=12), (2) Eri silkworm pupae ingestion group (ERI, n=12), and (3) combined concurrent training and Eri silkworm pupae ingestion group (CBT-ERI, n=12). Participants in the ERI and the CBT-ERI con-sumed 5-g Eri silkworm pupae/day (approximately 2.5-g linolenic acid). The concurrent training program comprised of supervised aerobic and resistance training: three 1-hr sessions/wk for 8 weeks. Body composi-tion, energy expenditure, and FAO at rest and during exercise, heart rate variability, and blood chemistry were measured before and after the 8-week interventions. Following the interventions, resting FAO, the natural logarithm of very low-frequency power (lnVLF), and high-sensi-tive C-reactive protein concentration significantly improved in both the ERI and the CBT-ERI. Only the CBT-ERI improved resting energy expen-diture, FAO during exercise, trunk and gynoid fat mass, total cholesterol concentration, the standard deviation of normal R-R intervals (SDNN), and the percentage difference between adjacent normal R-R intervals >50 ms. Furthermore, there were significant correlations between rest-ing energy expenditure and FAO, lnVLF and SDNN in the CBT-ERI. In conclusion, this study demonstrates that concurrent training together with dietary Eri silkworm pupae leads to increased energy expenditure through a significant increase in FAO at rest and during exercise, as well as reduced fat mass.

Body composition, not dietary fatty acid composition, explains metabolic responses following a high-fat meal in premenopausal normal-weight women: a single-blind, randomised, crossover study

The aim of this study was to examine the effect of three different fatty acid (FA)-rich meals enriched in either SFA, MUFA or PUFA on postprandial metabolic responses in premenopausal, normal-weight women. For this randomised, single-blind, crossover study, three high-fat (HF) meals rich in either SFA, MUFA or PUFA (65 % energy from fat; 35 % of participants’ total daily energy needs) were tested. For each visit, anthropometrics and RMR were measured following a 12–15 h fast. Then, participants consumed one of the HF meals, and respiratory gases were collected using indirect calorimetry for 3 h postprandially. Energy expenditure (EE) following a SFA-rich meal was significantly higher than a MUFA-rich meal (P = 0·04; η2 = 0·19), but SFA was not significantly different from PUFA. There was a trend towards significance in EE between PUFA and MUFA (P = 0·06). After adjusting for fat-free mass (FFM), there were no longer condition or time effects for EE, although FFM remained a significant predictor (P = 0·005; η2 = 0·45). There were no significant differences between conditions for dietary-induced thermogenesis or substrate oxidation. The relationship between fat mass (FM) and both total fat oxidation (r 0·62; P = 0·025) and total change in RER following a MUFA-rich meal was observed (r −0·55; P = 0·05). In conclusion, weight loss through increases in EE may be best achieved by increasing FFM rather than selection of FA type. Further, a relationship exists between FM and fat oxidation following a MUFA-rich meal, most likely due to an unidentified mechanism.

Protective Effects of a Discontinuous Treatment with Alpha-Lipoic Acid in Obesity-Related Heart Failure with Preserved Ejection Fraction, in Rats

Obesity induces hemodynamic and humoral changes that are associated with functional and structural cardiac remodeling, which ultimately result in the development of heart failure (HF) with preserved ejection fraction (HFpEF). In recent years, pharmacological studies in patients with HFpEF were mostly unsatisfactory. In these conditions, alternative new therapeutic approaches are necessary. The aim of our study was (1) to assess the effects of obesity on heart function in an experimental model and (2) to evaluate the efficacy of an alpha-lipoic acid (ALA) antioxidant treatment. Sprague-Dawley rats (7 weeks old) were either included in the control group (n = 6) or subjected to abdominal aortic banding (AAB) and divided into three subgroups, depending on their diet: standard (AAB + SD, n = 8), hypecaloric (AAB + HD, n = 8) and hypecaloric with discontinuous ALA treatment (AAB + HD + ALA, n = 9). Body weight (BW), glycemia, echocardiography parameters and plasma hydroperoxides were monitored throughout the study. After 36 weeks, plasma adiposity (leptin and adiponectin) and inflammation (IL-6 and TNF-alpha) markers, together with B-type natriuretic peptide and oxidative stress markers (end-products of lipid peroxidation and endogenous antioxidant systems) were assessed. Moreover, cardiac fiber diameters were measured. In our experiment, diet-induced obesity generated cardiometabolic disturbances, and in association with pressure-overload induced by AAB, it precipitated the onset of heart failure, cardiac hypertrophy and diastolic dysfunction, while producing a pro-oxidant and pro-inflammatory plasmatic status. In relationship with its antioxidant effects, the chronic ALA-discontinuous treatment prevented BW gain and decreased metabolic and cardiac perturbations, confirming its protective effects on the cardiovascular system.

Emerging insights on drug delivery by fatty acid mediated synthesis of lipophilic prodrugs as novel nanomedicines

Many drug molecules that are currently in the market suffer from short half-life, poor absorption, low specificity, rapid degradation, and resistance development. The design and development of lipophilic prodrugs can provide numerous benefits to overcome these challenges. Fatty acids (FAs), which are lipophilic biomolecules constituted of essential components of the living cells, carry out many necessary functions required for the development of efficient prodrugs. Chemical conjugation of FAs to drug molecules may change their pharmacodynamics/pharmacokinetics in vivo and even their toxicity profile. Well-designed FA-based prodrugs can also present other benefits, such as improved oral bioavailability, promoted tumor targeting efficiency, controlled drug release, and enhanced cellular penetration, leading to improved therapeutic efficacy. In this review, we discuss diverse drug molecules conjugated to various unsaturated FAs. Furthermore, various drug-FA conjugates loaded into various nanostructure delivery systems, including liposomes, solid lipid nanoparticles, emulsions, nano-assemblies, micelles, and polymeric nanoparticles, are reviewed. The present review aims to inspire readers to explore new avenues in prodrug design based on the various FAs with or without nanostructured delivery systems.

Effects of the juçara fruit supplementation on metabolic parameters in individuals with obesity: a double-blind randomized controlled trial

Adipose tissue inflammation has been proposed as a central mechanism connecting obesity with its metabolic and vascular complications due to the imbalance in the expression of several hormones and adipokines. Berries rich in polyphenols and unsaturated fatty acids have been able to prevent both obesity and adipose tissue inflammation, improving metabolic functions in human subjects and animal models of obesity. Juçara has been considered a super fruit owing to its nutritional composition and relevant biological activities with an interesting response in animals. Thus, we aimed to verify the potential antiobesogenic effect of juçara supplementation in humans. We conducted a double-blind, placebo-controlled, randomized trial with 35 adults with obesity of both sexes. They were assessed for resting metabolic rate, anthropometry and body composition, blood pressure, metabolic parameters and adipokines. Subsequently, they were randomized into two groups to use or not (placebo) 5 g lyophilized juçara for 6 weeks. Supplementation with juçara was significantly effective in reducing body fat, increasing high-density lipoprotein cholesterol and doubling serum adiponectin. Besides, juçara supplementation, high-density lipoprotein cholesterol and neck circumference were predictors to explain the enhancement in adiponectin. Juçara supplementation was determinant to improve adiponectin levels, and it may be considered a novel strategy for the treatment of obesity-related metabolic diseases.

The Effects of Diets Enriched in Monounsaturated Oleic Acid on the Management and Prevention of Obesity: a Systematic Review of Human Intervention Studies

Obesity is associated with an increased risk of several major noncommunicable diseases, and is an important public health concern globally. Dietary fat content is a major contributor to the increase in global obesity rates. Changes in dietary habits, such as the quality of fatty acids in the diet, are proposed to prevent obesity and its metabolic complications. In recent years, a number of studies have found that oleic acid (OA), the most common MUFA in daily nutrition, has protective effects against human disease. Importantly, there is emerging evidence indicating the beneficial effects of OA in regulating body weight. Accordingly, the objective of this systematic review was to investigate the effects of diets enriched in monounsaturated OA on the management and prevention of obesity, emphasizing possible mechanisms of action of OA in energy homeostasis. Searches were performed in PubMed/MEDLINE, ScienceDirect, Scopus, ProQuest, and Google Scholar databases for clinical trials that examined the effects of diets rich in OA on obesity. Of 821 full-text articles assessed, 28 clinical trials were included in the present study. According to the studies examined in this review, diets enriched in OA can influence fat balance, body weight, and possibly energy expenditure. Importantly, abdominal fat and central obesity can be reduced following consumption of high-OA-containing meals. Mechanistically, OA-rich diets can be involved in the regulation of food intake, body mass, and energy expenditure by stimulating AMP-activated protein kinase signaling. Other proposed mechanisms include the prevention of the nucleotide-binding oligomerization domain-like receptor 3/caspase-1 inflammasome pathway, the induction of oleoylethanolamide synthesis, and possibly the downregulation of stearoyl-CoA desaturase 1 activity. In summary, current findings lend support to advice not restricting consumption of OA-rich meals so as to maintain a healthy body weight.

Comparison of the effect of rapeseed oil or amaranth seed oil supplementation on weight loss, body composition, and changes in the metabolic profile of obese patients following 3-week body mass reduction program: a randomized clinical trial

BACKGROUND

Amaranth seed oil (ASO) and rapeseed oil (RSO) are functional foods that display antioxidant and hepatoprotective properties. These oils are also known to lower glucose and cholesterol levels. The current study compared the effects exerted by RSO and ASO on weight loss and metabolic parameters during a 3-week body mass reduction program.

METHODS

Eighty-one obese subjects (BMI > 30 kg/m2), aged 25-70 years, were enrolled in a 3-week body mass reduction program based on a calorie-restricted diet and physical activity. Participants were randomly categorized into an AO group (administered 20 mL/d of ASO), a RO group (administered 20 mL/d of RSO), and a C group (control; untreated). Anthropometric and metabolic parameters were measured at baseline and endpoint.

RESULTS

Significant decreases in weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), fat mass (FM), lean body mass (LBM), visceral fat mass (VFM), and total body water (TBW%) were observed in all groups (P <  0.05). No significant improvements were observed in the clinical parameters of group C. Fasting insulin (Δ - 5.9, and Δ - 5.7) and homeostatic model assessment of insulin resistance (HOMA-IR) (Δ - 1.1 and Δ - 0.5) were decreased in both RO and AO groups, respectively. Fasting glucose (Δ -8.5; P = 0.034), total cholesterol (Δ -14.6; P = 0.032), non-HDL cholesterol (Δ 15.9; P = 0.010), TG/HDL ratio (Δ -0.6; P = 0.032), LDL cholesterol (Δ -12.3; P = 0.042), and triglycerides (Δ -6.5; P = 0.000) were significantly improved in the AO group, compared to the RO group.

CONCLUSIONS

The 3-week body mass reduction intervention caused a significant reduction in the weight, BMI, WC, HC, FM, and VFM of all groups. Except for HOMA-IR, there were no statistical differences between the clinical parameters of all groups. However, a trend toward improved insulin levels and HDL% was noticeable in AO and RO. Therapies involving edible oils with high nutritional value, such as RSO and ASO, show potential for improving metabolic measurements during body mass reduction programs. Thus, obese patients undertaking weight reduction programs may benefit from RSO and ASO supplementation.

TRIAL REGISTRATION

retrospectively registered, DRKS00017708.

An Insight into Diversity and Functionalities of Gut Microbiota in Insects

The gut microbiota has long been of research interests due to its nutritional importance for many insects. It has been demonstrated that diversity of gut microbiota in insects can be modulated by many factors, including habitats, feeding preference, etc. Besides, the community structure of gut microbiota could also be altered during the different life stages of host insects. With development of conventional culture-dependent technologies and advanced culture-independent technologies, comprehensive and deep understanding of the functions of gut microbiota and their relationship with host insects were achieved, especially for the nutrient metabolic process mediated by them. In this review, we summarized the gut microbiota composition, major methods for gut microbiota characterization, and vital nutrient metabolic process mediated by gut microbiota in different insects. The increasing knowledge on the modulation of gut microbiota will help us for the comprehension of the contribution of gut microbiota to the nutritional metabolism of insects, prompting their growth and health.

Ileal transposition: A non-restrictive bariatric surgical procedure that reduces body fat and increases ingestion-related energy expenditure

BACKGROUND

Ileal Transposition (IT) was developed as a model to study body weight reduction without the restrictive or malabsorptive aspects of other bariatric surgeries, but the exact mechanisms of the alterations in body weight after IT are not completely understood.

OBJECTIVE

To provide a detailed description of the surgical procedure of IT, and describe its effect on energy balance parameters.

METHODS

Adult male Lewis rats underwent either IT (IT+) or sham (IT-) surgery. Following surgery body weight and energy intake were monitored. After attaining weight stability (> 30 days), energy expenditure and its components were assessed using indirect calorimetry at a day of fasting, limited intake, and ad libitum intake. At the end of the study body composition analysis was performed.

RESULTS

IT+ resulted in transiently reduced energy intake, increased ingestion-related energy expenditure (IEE) and decreased body and adipose tissue weight when compared to IT-. At weight stability, neither energy budget (i.e., energy intake - energy expenditure), nor energy efficiency was different in IT+ rats compared to IT-.

CONCLUSION

Our data show that the primary cause of weight reduction following IT+ is a transient reduction in energy intake. If the increased IEE is related to a higher level of satiety, compensatory feeding to bridge body weight difference between IT+ and IT- rats is less likely to occur.

Both Dietary Ratio of n-6 to n-3 Fatty Acids and Total Dietary Lipid Are Positively Associated with Adiposity and Reproductive Health in Zebrafish

BACKGROUND

Controversial findings have been reported in human and animal studies regarding the influence of n-6 (ω-6) to n-3 (ω-3) fatty acid ratios on obesity and health. Two confounding factors may be related to interactions with other dietary lipid components or sex-specific differences in fatty acid metabolism.

OBJECTIVE

This study investigated main and interactive effects of total dietary lipid, ratio of n-6 to n-3 fatty acids, and sex on growth, adiposity, and reproductive health in wild-type zebrafish.

METHODS

Male and female zebrafish (3 wk old) were fed 9 diets consisting of 3 ratios of n-6 to n-3 fatty acids (1.4:1, 5:1, and 9.5:1) varied within 3 total lipid amounts (80, 110, and 140 g/kg) for 16 wk. Data were then collected on growth, body composition (determined by chemical carcass analysis), and female reproductive success (n = 32 breeding events/diet over 4 wk). Main and interactive effects of dietary lipid and sex were evaluated with regression methods. Significant differences within each dietary lipid component were relative to the intercept/reference group (80 g/kg and 1.4:1 ratio).

RESULTS

Dietary lipid and sex interacted in their effects on body weight (P = 0.015), total body length (P = 0.003), and total lipid mass (P = 0.029); thus, these analyses were stratified by sex. Female spawning success decreased as dietary total lipid and fatty acid ratio increased (P = 0.030 and P = 0.026, respectively). While total egg production was not associated with either dietary lipid component, females fed the 5:1 ratio produced higher proportions of viable embryos compared with the 1.4:1 ratio [median (95% CI): 0.915 (0.863, 0.956) vs 0.819 (0.716, 0.876); P < 0.001].

CONCLUSIONS

Further characterization of dietary lipid requirements will help define healthy balances of dietary lipid, while the sex-specific responses to dietary lipid identified in this study may partially explain sex disparities in the development of obesity and its comorbidities.