Measures of adiposity and body fat distribution in relation to serum folate levels in postmenopausal women in a feeding study

Understanding the Impact of Vitamin B Supplements on a Saudi Population

Introduction B vitamins help generate energy within cells. A significant portion of populations in developed countries suffer a deficiency in one or more B vitamins. This study assesses the use of vitamin B supplements and their effects. Methodology This cross-sectional study was conducted using public participants in Saudi Arabia. Participants from all over Saudi Arabia were recruited through self-conducted surveys to study the effects of using vitamin B supplements on appetite, BMI, energy, and sleep, and to identify any side effects in participants. Inclusion criteria included age (18 years or older) and use of vitamin B supplements. Children, pregnant women, adults who had never used vitamin B, and those not willing to participate in the study were excluded. Results In total, 1,521 adults were recruited. Most of the participants were young Saudi Females. While taking vitamin B supplements, a minority of participants complained of mild gastrointestinal upset, but a significant proportion experienced no side effects. In this study, a significant proportion of participants experienced an increase in appetite, which was associated with a significant increase in BMI after taking vitamin B supplements. This study also explored increases in energy, which were significant and associated with significant increases in sleeping time. Male participants in the present study noticed a significant increase in erectile dysfunction (ED). Conclusions This study found significant effects of vitamin B supplements on BMI, appetite, energy, and sleep, as well as an increase in ED in male participants. More studies are needed to further explore these findings.

Association between Variation in Body Fat Mass Magnitude and Intake of Nutrients, including Carbohydrates, Fat, and B Vitamins, in a Cohort of Highly Trained Female Athletes

The most common sports nutrition strategies were constructed not only for maximizing musculoskeletal adaptations to exercise, but also to minimize health risks in athletes. Given the lack of research highlighting the potential effects of the intake of carbohydrates, fats, and B vitamins on body fat percentage in a population of female athletes, this study aimed to elucidate whether the intake of macronutrients and B vitamins could be associated with the variation in body fat percentage in a cohort of professional female athletes. This cross-sectional study was weighted to represent Lithuanian elite female athletes (n = 89). The dietary assessment of the female athletes was carried out using a 3-day dietary recall method. Their body composition was assessed using the bioelectrical impedance analysis method. For females, the reported average intakes of energy, carbohydrates, protein, and fat were 2475 kcal/day, 5.1 g/kg/day, 1.5 g/kg/day, and 36.7%, respectively. Excess B vitamin intake was revealed, ranging within plus 1-2 standard deviations (SDs) around the mean requirements. As a consequence, excessive body fat percentage was potentially factored as a negative outcome in maintaining optimal body composition in female athletes. Multivariate logistic regression analysis of a sample of female athletes revealed that, despite a slightly positive energy balance (∆ 95 kcal/day), the carbohydrate-deficient diet (adjusted odds ratio (aOR) 0.3, 95% confidence interval (CI) 0.1; 0.7), along with higher intakes of vitamin B1 (aOR 2.9, 95% CI 2.6; 7.8), vitamin B2 (aOR 6.7, 95% CI 1.1; 8.3), and vitamin B3 (aOR 1.8, 95% CI 1.4; 7.8) from food, was associated with a lower percentage of body fat. Therefore, more attention should be given to the intake of B vitamins in professional athletes with a range of body fat mass percentages for the purpose of achieving long-term goals of maintaining body composition and fitness.

Association of the DNA Methylation of Obesity-Related Genes with the Dietary Nutrient Intake in Children

The occurrence of obesity stems from both genetic and external influences. Despite thorough research and attempts to address it through various means such as dietary changes, physical activity, education, and medications, a lasting solution to this widespread problem remains elusive. Nutrients play a crucial role in various cellular processes, including the regulation of gene expression. One of the mechanisms by which nutrients can affect gene expression is through DNA methylation. This modification can alter the accessibility of DNA to transcription factors and other regulatory proteins, thereby influencing gene expression. Nutrients such as folate and vitamin B12 are involved in the one-carbon metabolism pathway, which provides the methyl groups necessary for DNA methylation. Studies have shown that the inadequate intake of these nutrients can lead to alterations in DNA methylation patterns. For this study, we aim to understand the differences in the association of the dietary intake between normal weight and overweight/obese children and between European American and African American children with the DNA methylation of the three genes NRF1, FTO, and LEPR. The research discovered a significant association between the nutritional intake of 6-10-years-old children, particularly the methyl donors present in their diet, and the methylation of the NRF1, FTO, and LEPR genes. Additionally, the study emphasizes the significance of considering health inequalities, particularly family income and maternal education, when investigating the epigenetic impact of methyl donors in diet and gene methylation.

Joint effect of maternal pre-pregnancy body mass index and folic acid supplements on gestational diabetes mellitus risk: a prospective cohort study

Background

The joint effect of folic acid (FA) supplements and maternal pre-pregnancy body mass index (BMI) on gestational diabetes mellitus (GDM) has not been fully addressed. This study aimed to examine the joint effect of FA supplements and pre-pregnancy BMI on GDM.

Methods

Pregnant women at 4 to 14 weeks of gestation (n = 3186) were recruited during their first prenatal visit in Qingdao from May 1, 2019, to June 27, 2021. The main outcome was GDM at 24–28 weeks’ gestation. Screening was based on 75 g 2-hour oral glucose tolerance (OGTT), a fasting glucose ≥ 5.1 mmol/L, or a 1-hour result ≥ 10.0 mmol/L, or a 2-hour result ≥ 8.5 mmol/L. The interactive effect of FA supplements and pre-pregnancy BMI on GDM was examined using logistic regression analysis and ratio of odds ratios (ROR) was used to compare subgroup differences.

Results

Overall, 2,095 pregnant women were included in the analysis, and GDM incidence was 17.76%. Compared with women with pre-pregnancy BMI lower than 25.0 kg/m² and FA-Sufficient supplements ≥ 400 µg/day (FA-S) population, the adjusted odds ratios (aORs) of FA-S and FA-Deficiency supplements < 400 µg/d (FA-D) were 3.57 (95% confidence interval [CI]: 2.02–6.34) and 10.82 (95% CI: 1.69–69.45) for the obese women (BMI ≥ 30.0 kg/m²), and the aORs of FA-S and FA-D were 2.17 (95% CI: 1.60–2.95) and 3.27 (95% CI: 1.55–6.92) for overweight women (25.0 kg/m² ≤ BMI < 30.0 kg/m²). However, the risk of GDM did not differ significantly between the FA-D and the FA-S group in pre-pregnancy obese women (ROR = 2.70, 95%CI: 0.47–2.30), or overweight women (ROR = 0.66, 95%CI: 0.30–1.49). After further stratification of FA supplementation time, F-D and FA-S in obese women showed an interaction when FA supplement intake time < 3 months. However, there was no significant difference between subgroups (ROR = 1.63, 95% CI: 0.37–7.04).

Conclusion

Maternal pre-pregnancy BMI was associated with the incidence of GDM, the dose of FA supplementation from pre-pregnancy to early pregnancy was not found to be related to the incidence of GDM. The dosage of FA supplement was not associated with GDM irrespective of maternal pre-pregnancy BMI.

Association between Vitamin B and Obesity in Middle-Aged and Older Chinese Adults

OBJECTIVE

Previous studies have found that obese people have lower levels of vitamin B, but most have focused on obesity as defined by body mass index (BMI), and its relationship with other types of obesity is unclear. The aim of this study was to explore the relationship between vitamin B levels and obesity assessed by different definitions among Chinese middle-aged and older community-dwelling adults.

METHODS

This cross-sectional study included 887 participants aged 45 years and older (45-82 years). The concentrations of vitamin B (B₁, B₂, B₆, and B₉) were measured by robotic dry blood spot extraction systems in combination with liquid chromatography-tandem mass spectrometry. BMI, body fat percentage (BF%), visceral fat area (VFA), and waist circumference (WC) were used to diagnose obesity. VFA and BF% were assessed by bioelectrical impedance analysis. The logistic regression model was used to assess the associations between vitamin B levels and the odds of obesity.

RESULTS

The average age of all participants was 60.77 (SD 6.33) years. The prevalence of obesity varied from 8.6% to 52.4% depending on different diagnostic criteria. After adjusting for covariates, a negative correlation was observed between vitamin B₁ level and obesity according to the criteria of WC, VFA, and BF%, and the adjusted odds ratio (OR) was 0.47, 0.52, and 0.46, respectively. When using WC and BF% to define obesity, higher quartiles of vitamin B₂ were negatively associated with the odds of obesity (OR: 0.62 and 0.62, respectively). Vitamin B₆ was inversely associated with VFA-defined and BF%-defined obesity (OR: 0.64 and 0.64, respectively). When using VFA and BF% to define obesity, a negative correlation was observed in vitamin B₉ (OR: 0.61 and 0.67, respectively).

CONCLUSIONS

Vitamin B (B₁, B₂, B₆, and B₉) level was negatively related to obesity (defined by WC, VFA, or BF%) in Chinese middle-aged and older adults.

Nutrient Patterns and Its Association and Metabolic Syndrome among Chinese Children and Adolescents Aged 7-17

This study was designed to explore the associations between nutrient patterns (NPs) and metabolic syndrome (MetS) and its five components among Chinese children and adolescents aged 7-17. The required data of participants were collected from the China National Nutrition and Health Surveillance of Children and Lactating Mothers in 2016-2017. Ultimately, 13,071 participants were included. Nutrient patterns were obtained by means of factor analysis. Multivariate logistic regression analysis was conducted to evaluate the association between nutrient patterns with MetS and its components. After adjusting covariates, the results of logistic regression models revealed that high-carbohydrate patterns were associated with the presence of abdominal obesity. The high-animal protein pattern was negatively associated with high triglyceride (TG) and low high-density lipoprotein cholesterol (HDL-C). The high-sodium-and-fat pattern had a negative relationship with elevated blood pressure (BP) and was positively associated with low HDL-C. The high-Vitamin D-and-Vitamin B₁₂ pattern had protective effects on MetS, high TG, and low HDL-C. Further large-scale longitudinal investigations are necessary in the future.

Methylenetetrahydrofolate Reductase C677T Gene Variant in Relation to Body Mass Index and Folate Concentration in a Polish Population

BACKGROUND

Methylenetetrahydrofolate reductase (MTHFR) is an enzyme responsible for producing an active form of folate. The MTHFR T677T genotype may have adverse health effects associated with weight gain and a reduction in folate availability.

AIM

In this study, we examined the influence of the MTHFR C677T variant on BMI and determined its role as a risk factor for obesity. We also assessed the relationships between the MTHFR C677T genotype and folate and vitamin B₁₂ concentrations in subjects before and after radical weight loss.

METHODS

The study group consisted of 1712 Caucasian adults of Polish nationality with a wide range of body mass indexes (BMIs). DNA was extracted from the blood, and the C677T variant was tested with RFLP-PCR and real-time-PCR.

RESULTS

There was no significant influence found for the MTHFR 677 TT genotype on BMI or the obesity risk in codominant, dominant or recessive inheritance models. Individuals with obesity and the TT genotype had significantly lower folate concentrations. After radical weight reduction, the impact of the risk genotype, as well as homeostasis between folate and vitamin B₁₂ in TT homozygotes, seems to be attenuated.

CONCLUSION

Although the MTHFR 677TT genotype is not directly related to a higher BMI in Polish adults, it has a detrimental effect on folate concentrations in individuals with high BMI values.

Central adiposity increases the odds for plasma folate deficiency among Chinese women of reproductive age

Objective

To explore the association between adiposity and plasma folate deficiency odds among women of reproductive age in China.

Methods

A cross-sectional survey on nutritional status among women of reproductive aged 18-30 years in 2005-2006 in China was conducted. General adiposity was defined as body mass index (BMI) ≥24 kg/m2, and central adiposity was defined as waist circumference >80 cm. A plasma folate concentration <10.5 nmol/L (measured through microbiological assay) was defined as plasma folate deficiency. Odds ratios (ORs) and 95% confidence intervals (CIs) for plasma folate deficiency were calculated using a logistic regression model, with adjustment for potential confounders.

Results

A total of 3,076 women of reproductive age were included in the final analysis. Compared to women with normal BMI and WC, women with both general and central adiposity had the highest odds for plasma folate deficiency (OR = 3.107, 95% CI: 1.819-5.307). Women with exclusively central adiposity had excess odds for plasma folate deficiency (WC > 80 cm, BMI <24 kg/m2; OR = 2.448, 95% CI: 1.144-5.241), which was higher than women with exclusively general adiposity (BMI ≥ 24 kg/m2, WC ≤ 80 cm; OR = 1.709, 95% CI: 1.259-2.319). The combined use of BMI and WC can detect more women (11.7%) at higher plasma folate deficiency odds than either used alone.

Conclusions

Women with central adiposity in normal weight have higher odds for plasma folate deficiency than those with general obesity only. Early screening for central adiposity among women of reproductive age would be meaningful to prevent folate deficiency and improve life-cycle health.

Non-Linear Association between Serum Folate Concentration and Dyslipidemia: Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2018

Objectives

We aimed to evaluate the association between serum folate concentration and prevalence of dyslipidemia.

Methods

A total of 4,477 adults (2,019 men and 2,458 women) enrolled in the Korea National Health and Nutrition Examination Survey (KNHANES) 2016-2018 were included. Serum samples were used to access folate concentration and total cholesterol (TC), triglyceride (TG), low-density lipoprotein (LDL)-cholesterol, and high-density lipoprotein (HDL)-cholesterol levels. Multivariate logistic regression with a sampling weight was used to calculate odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Elevated TC, TG, LDL-cholesterol and HDL-cholesterol were observed in 506 (11.3%), 646 (14.4%), 434 (9.7%), and 767 (17.1%) participants, respectively. We found non-linear trends between serum folate concentration and prevalence of hypercholesterolemia and hyper-LDL cholesterolemia from the restricted cubic smoothing spline. A higher prevalence of hypercholesterolemia was observed among participants in the 1st tertile serum folate concentration group (OR [95% CI] = 1.38 [1.05-1.79]) compared to those in the 2nd tertile group. On the other hand, a higher prevalence of hyper-LDL cholesterolemia was identified for both the 1st and 3rd serum folate concentration tertile groups (OR [95% CI]: 1.49 [1.08-2.05] and 1.63 [1.20-2.20], respectively); furthermore, in these tertiles, the prevalence of hyper-LDL cholesterolemia was more pronounced among obese participants.

Conclusion

Non-linear associations may exist between serum folate concentration and the prevalence of hypercholesterolemia and hyper-LDL cholesterolemia in adults. The findings suggest that more accurate recommendations about folate intake and folic acid fortification and supplementation should be provided.

Folate Deficiency Increased Lipid Accumulation and Leptin Production of Adipocytes

Imbalanced dietary habits are closely associated with poor micronutrients status and the development of obesity. Previous studies have shown that serum folate level is decreased in obese individuals. However, whether folate deficiency could result in adiposity is still unclear. The aim of this study was to investigate the effects of dietary folate on lipid accumulation and leptin production using both in vivo and in vitro studies. Male C57BL/6 mice were fed with a diet with (f1) or without (f0) folate in a high-fat (HF) diet containing high-sucrose (HFS-f1, HFS-f0) for 4.5-5 months in Experiment 1, or an HF diet (HF-f1, HF-f0) for 12 months in Experiment 2, or an HF diet containing high-fructose (HFF-f1, HFF-f0) for 12 months in Experiment 3, compared with the normal-fat (NF-f1, NF-f0) diet, respectively. The serum levels of folate and leptin, white adipose tissue (WAT), size of adipocytes, hepatic contents of triglyceride (TG), and cholesterol were measured. In vitro study, TG contents, proinflammatory cytokines, leptin, and expressions of hypoxia-inducible factor (HIF)-1α and lipogenesis-related genes of 3T3-L1 adipocytes cultured with (f1) or without (f0) folate were assayed. The results showed that folate deficiency together with a high-fat diet (HFS-f0, HF-f0, HFF-f0) had higher WAT mass, adipocyte size, serum leptin level, and hepatic TG compared to those of the folate-sufficient groups (HFS-f1, HF-f1, and HFF-f1). Folate deficiency with a high-fat high -sucrose or -fructose diet (HFS-f0, HFF-f0) significantly increased the body weight of the mice. Increased intracellular TG, leptin, monocyte chemotactic protein (MCP)-1 and interleukin (IL)-6 levels, and the expression of Hif1α and lipogenesis-related genes Cebpα, Cebpβ, Acc1, Fasn, and Fabp4 were also detected in folate-deficient 3T3-L1 adipocytes. Our results suggested that folate deficiency increased lipid accumulation and leptin production of adipocytes, and thus, inadequate folate status might be one of the risk factors for adiposity.

Inverse Association of Serum Folate Level with Metabolic Syndrome and Its Components in Korean Premenopausal Women: Findings of the 2016–2018 Korean National Health Nutrition Examination Survey

Research on the association of serum folate levels with metabolic syndrome (MetS) in premenopausal women is lacking. This study was aimed to investigate this association in 1730 premenopausal women using the 2016 to 2018 Korean National Health and Nutrition Examination Survey data. Participants’ mean age and BMI were 35.9 years and 22.7 kg/m2, respectively. Participants were divided into three groups according to serum folate tertiles. Odds ratios (OR) and 95% confidence intervals (CIs) for abdominal obesity, elevated blood pressure (BP), high fasting plasma glucose (FPG), high triglycerides (TG), low high-density lipoprotein cholesterol (HDL-C), and MetS were calculated in multiple logistic regression models adjusted for possible confounders, by serum folate level tertiles. Prevalence of MetS (14.9, 11.0, and 8.6%); abdominal obesity (17.8, 16.0, and 11.4%); high TG (17.5, 14.0, and 11.1%); and low HDL-C (50.3, 44.6, and 42.5%) decreased with increasing folate level tertile. Prevalence of elevated BP (14.3, 12.0, and 11.7%) and high FPG (11.9, 15.8, and 13.0%) showed no significant differences according to serum folate level tertiles. The multivariate-adjusted ORs (95% CIs) for MetS, abdominal obesity, elevated BP, high TG, and low HDL-C in the highest folate level tertile were 2.17 (1.46–3.22), 1.80 (1.25–2.60), 1.77 (1.16–2.70), 1.90 (1.35–2.67), and 1.49 (1.14–1.94), respectively. The ORs for high FPG did not show significant differences according to serum folate level tertiles. In conclusion, serum folate levels were inversely associated with an increased risk of MetS in Korean premenopausal women. These results suggest that MetS can be prevented and managed by improving the serum folate levels in premenopausal women.

Association of Obesity with the Risk of Hyperhomocysteinemia among the Chinese Community Residents: A Prospective Cohort Study in Shanghai, China

A prospective community-based cohort study was conducted to investigate the effects of obesity on hyperhomocysteinemia (HHcy) in community residents from Shanghai, China, with a median follow-up period of 2.98 years. The exposures were high body mass index (BMI) (BMI ≥ 28.0 kg/m²) and high waist circumference (WC) (WC ≥ 85.0 cm for female and WC ≥ 90.0 for male) at baseline investigation, and the outcome was the incident of HHcy after the follow-up. A restricted cubic spline (RCS) was performed to assess the possible nonlinear relationship of BMI and WC with HHcy. A Cox proportional hazard regression model was used to evaluate the association between BMI and WC measured obesity and the risk of HHcy (Hcy level > 15 µmol/L). No significant non-linearity was found between BMI and WC with HHcy. Cox regression model showed that underweight measured by BMI was negatively associated with the risk of HHcy after controlling for confounder variables (adjusted HR = 0.64, 95% CI = 0.42 to 0.99). While abdominal obesity was positively associated with the risk of HHcy for those without CVD-related comorbidities (adjusted HR = 1.26, 95% CI = 1.05 to 1.51). Our results suggested that individuals could maintain a relatively low BMI and normal WC to lower the risk of HHcy.

Associations between dietary intake of B vitamins and cardiovascular risk factors in elderly men: A cross-sectional study

OBJECTIVE

Low intake of B vitamins can lead to hyperhomocysteinaemia, which is reported as a risk factor for cardiovascular disease (CVD). However, little is known about this relationship. Therefore, we decided to examine the association between dietary intake of B vitamins and cardiovascular risk factors in elderly men.

METHODS

The present cross-sectional study consisted of 357 elderly men. Dietary intake was assessed using a validated and reliable food frequency questionnaire. All biochemical factors [fasting blood sugar (FBS), triglyceride (TG), high-sensitivity C-reactive protein (hs-CRP), interleukin 6 (IL-6) and tumour necrosis factor-α (TNF-α)], waist circumference (WC) and blood pressure (BP) were assessed using standard methods.

RESULTS

A significant inverse association was observed between high dietary intake of total B vitamins (OR_{Total B vitamins} : 0.30; 95% CI: 0.10, 0.86; P = .01) and vitamin B9 (OR_{vitamin B9} : 0.20; 95% CI: 0.02, 0.52; P = .002) with high WC. Furthermore, an inverse association was observed between high dietary intake of vitamin B6 (OR_{vitamin B6} : 0.28; 95% CI: 0.08, 1.00; P = .05) and vitamin B9 (OR_{vitamin B9} : 0.20; 95% CI: 0.06, 0.70; P = .01) with hs-CRP level.

CONCLUSIONS

In elderly men, a high dietary intake of total B vitamins and vitamin B9 was associated with lower odds of having a high WC. Similarly, high dietary intake of vitamin B6 and B9 was associated with lower odds of having a high hs-CRP level.

GeNuIne (gene-nutrient interactions) Collaboration: towards implementing multi-ethnic population-based nutrigenetic studies of vitamin B12 and D deficiencies and metabolic diseases

Gene-nutrient interactions (GeNuIne) collaboration, a large-scale collaborative project, has been initiated to investigate the impact of gene-nutrient interactions on cardiometabolic diseases using population-based studies from ethnically diverse populations. In this project, the relationship between deficiencies of vitamins B12 and D, and metabolic diseases was explored using a nutrigenetic approach. A genetic risk score (GRS) analysis was used to examine the combined effect of several genetic variations that have been shown to be associated with metabolic diseases and vitamin B12 and D deficiencies, respectively. In Sri Lankan, Indonesian and Brazilian populations, those carrying a high B12-GRS had an increased risk of metabolic diseases under the influence of dietary protein, fibre and carbohydrate intakes, respectively; however, in Asian Indians, genetically instrumented metabolic disease risk showed a significant association with low vitamin B12 status. With regards to nutrigenetic studies on vitamin D status, although high metabolic-GRS showed an interaction with dietary carbohydrate intake on vitamin D status, the study in Indonesian women demonstrated a vitamin D GRS-carbohydrate interaction on body fat percentage. In summary, these nutrigenetic studies from multiple ethnic groups have provided evidence for the influence of the dietary factors on the relationship between vitamin B12/D deficiency and metabolic outcomes. Furthermore, these studies highlight the existence of genetic heterogeneity in gene-diet interactions across ethnically diverse populations, which further implicates the significance of personalised dietary approaches for the prevention of these micronutrient deficiencies and metabolic diseases.

The Concept of Folic Acid in Health and Disease

Folates have a pterine core structure and high metabolic activity due to their ability to accept electrons and react with O-, S-, N-, C-bounds. Folates play a role as cofactors in essential one-carbon pathways donating methyl-groups to choline phospholipids, creatine, epinephrine, DNA. Compounds similar to folates are ubiquitous and have been found in different animals, plants, and microorganisms. Folates enter the body from the diet and are also synthesized by intestinal bacteria with consequent adsorption from the colon. Three types of folate and antifolate cellular transporters have been found, differing in tissue localization, substrate affinity, type of transferring, and optimal pH for function. Laboratory criteria of folate deficiency are accepted by WHO. Severe folate deficiencies, manifesting in early life, are seen in hereditary folate malabsorption and cerebral folate deficiency. Acquired folate deficiency is quite common and is associated with poor diet and malabsorption, alcohol consumption, obesity, and kidney failure. Given the observational data that folates have a protective effect against neural tube defects, ischemic events, and cancer, food folic acid fortification was introduced in many countries. However, high physiological folate concentrations and folate overload may increase the risk of impaired brain development in embryogenesis and possess a growth advantage for precancerous altered cells.

Vitamins and non-alcoholic fatty liver disease: A Molecular Insight⋆

The incidence of non-alcoholic fatty liver disease (NAFLD) is rising rapidly across the globe. NAFLD pathogenesis is largely driven by an imbalance in hepatic energy metabolism and at present, there is no approved drug for its treatment. The liver plays a crucial role in micronutrient metabolism and deregulation of this micronutrient metabolism may contribute to the pathogenesis of NAFLD. Vitamins regulate several enzymatic processes in the liver, and derangement in vitamin metabolism is believed to play a critical role in NAFLD progression. The anti-oxidant activities of vitamin C and E have been attributed to mitigate hepatocyte injury, and alterations in the serum levels of vitamin D, vitamin B12 and folate have shown a strong correlation with NAFLD severity. This review aims to highlight the role of these vitamins, which represent promising therapeutic targets for the management of NAFLD.

Older adults with obesity have higher risks of some micronutrient inadequacies and lower overall dietary quality compared to peers with a healthy weight, National Health and Nutrition Examination Surveys (NHANES), 2011-2014

OBJECTIVE

To evaluate total usual intakes and biomarkers of micronutrients, overall dietary quality and related health characteristics of US older adults who were overweight or obese compared with a healthy weight.

DESIGN

Cross-sectional study.

SETTING

Two 24-h dietary recalls, nutritional biomarkers and objective and subjective health characteristic data were analysed from the National Health and Nutrition Examination Survey 2011-2014. We used the National Cancer Institute method to estimate distributions of total usual intakes from foods and dietary supplements for eleven micronutrients of potential concern and the Healthy Eating Index (HEI)-2015 score.

PARTICIPANTS

Older adults aged ≥60 years (n 2969) were categorised by sex and body weight status, using standard BMI categories. Underweight individuals (n 47) were excluded due to small sample size.

RESULTS

A greater percentage of obese older adults compared with their healthy-weight counterparts was at risk of inadequate Mg (both sexes), Ca, vitamin B6 and vitamin D (women only) intakes. The proportion of those with serum 25-hydroxyvitamin D < 40 nmol/l was higher in obese (12 %) than in healthy-weight older women (6 %). Mean overall HEI-2015 scores were 8·6 (men) and 7·1 (women) points lower in obese than in healthy-weight older adults. In addition, compared with healthy-weight counterparts, obese older adults were more likely to self-report fair/poor health, use ≥ 5 medications and have limitations in activities of daily living and cardio-metabolic risk factors; and obese older women were more likely to be food-insecure and have depression.

CONCLUSIONS

Our findings suggest that obesity may coexist with micronutrient inadequacy in older adults, especially among women.

Dynamics and interactions of cobalamin and folate status during advanced aging - a longitudinal study in a community-dwelling cohort with multiple follow-ups

BACKGROUND

Older people are reported to be prone to imbalances between cobalamin and folate status with possible adverse effects on health. This longitudinal study investigates dynamics and interactions of cobalamin and folate status in a cohort of community-dwelling older adults by considering possible influencing factors.

METHODS

In total, 332 subjects ≥ 60 years were investigated over a mean observation period of 12 years. Data collection included serum cobalamin, folate and creatinine, dietary intakes of cobalamin, folate and alcohol, use of supplements, body composition, smoking behavior, and diseases. Linear mixed-effects models with repeated measurements were used to investigate the influence of variables on serum cobalamin and folate.

RESULTS

At baseline, median cobalamin intake exceeded the dietary reference value (DRV), while median folate intake was considerably below DRV. In most subjects, serum concentrations of both vitamins were within reference ranges. For serum cobalamin, apart from supplement use (Parameter estimate [95% confidence interval]: 130.17 [53.32, 207.01]), the main positive predictor was serum folate (4.63 [2.64, 6.62]). For serum folate, serum creatinine (10.85 [4.85, 16.86]), use of supplements (7.86 [5.05, 10.67]), serum cobalamin (0.01 [< 0.01, 0.01]), and dietary folate intake (0.02 [0.01, 0.03]) were positive predictors. No main effects of age, sex, body composition, alcohol intake or smoking were found after adjusting for simultaneous inference.

CONCLUSIONS

Advancing age, per se, is no risk factor for a decline in serum concentrations of cobalamin or folate in subjects ≥ 60 years. Suboptimal folate intake may limit the function of folate regarding the supply of methyl groups for methylation of cobalamin and subsequent creatine biosynthesis. The positive association of serum creatinine with folate deserves further exploration with regard to its possible relevance for maintaining energy dependent functional integrity in the course of ageing.

Low folate intake and serum levels are associated with higher body mass index and abdominal fat accumulation: a case control study

BACKGROUND

The link between folate metabolism and obesity has recently been underlined, suggesting that folate deficiency may lead to body weight gain and adiposity. We thus wished to determine whether the inefficiency in folate metabolism caused by genetic variation in the MTHFR and DHFR genes in folate metabolism, or inadequate folate intake, is associated with obesity.

METHODS

A case-control study including 421 healthy participants (aged 20-40) was performed in Poznań, Poland. The cases were 213 subjects with BMI > 25 kg/m2, while the controls were 208 subjects with BMI < 25 kg/m2. Genotyping of rs70991108 (DHFR) and rs1801133 (MTHFR) was performed using TaqMan probes. Serum folate concentrations were measured using an enzyme-linked immunosorbent assay and homocysteine was assessed with high performance liquid chromatography.

RESULTS

Subjects with overweight and obesity had 12% lower folate intake (p < 0.05) and 8.5% lower folate serum concentrations (p < 0.01) than the controls. Serum folate concentrations and folate intake were inversely associated with body fat percentage (p < 0.05) and waist circumference (p < 0.05 and p < 0.001, respectively). Serum folate concentration, though not folate intake, was negatively associated with WHR and BMI (p < 0.05, for both associations).

CONCLUSIONS

Lower folate intake and serum levels are weakly, but independently, associated with greater body weight and central adiposity in people aged 20-40. MTHFR and DHFR polymorphism seems not to have significant impact on body weight.

One-Carbon Metabolism and Nonalcoholic Fatty Liver Disease: The Crosstalk between Nutrients, Microbiota, and Genetics

The prevalence of nonalcoholic fatty liver disease (NAFLD) is increasing worldwide. Its etiology includes nutritional, genetic, and lifestyle factors. Several mechanisms may link one-carbon metabolism - the associated metabolic pathways of folate, methionine, and choline - to the onset of NAFLD. In this review, we attempted to assess how choline, folate, methionine, and betaine affect NAFLD development, mainly through their role in the secretion of very low-density lipoproteins (VLDL) from the liver. We also reviewed recent articles that have described the relation between microbiota metabolism and NAFLD progression. Moreover, we describe the effect of single-nucleotide polymorphisms (SNP) in genes related to one-carbon metabolism and disease prevalence. We additionally seek SNP identified by genome-wide associations that may increase the risk of this disease. Even though the evidence available is not entirely consistent, it seems that the concentrations of choline, methionine, folate, and betaine may affect the progression of NAFLD. Since there is no effective therapy for NAFLD, further investigations into the link between nutrition, gut microbiota, genetic factors, and NAFLD are still necessary, with a particular emphasis on methyl donors.

Obesity is associated with folate metabolism

Objective: The aim of the present study is to perform a systemic review of the previous studies executed on the association between obesity and folate. Method: In the present research, the selected keywords were scanned on the PubMed, Web of Science, Cochrane and Lilac databases between May and June, 2017 through Gazi University's network. In total, 4236 clinical, randomized controlled, cross-sectional and prospective studies were determined and 17 of these that specifically fit the aims of the present research were reviewed. This study involved an electronic literature search of databases on folic acid and obesity published in the English language between 2000 and 2016. Results: Of the 17 studies, 5 were based on folic acid supplementation and 12 were related with participants' folate status. As a general consequence of both intake and serum/status measurements of folic acid supplementation: It was found that obesity-associated metabolic changes might affect individual folate use and obese individuals had lower serum folate levels, although there was no change in folate intake. Conclusion: Overweight and obese individuals have lower serum folate concentrations when compared with individuals with normal weight. It is explained by increased use of folic acid, urinary excretion, dilution of blood volume, different levels in different tissues and changes in the endocrine functions of folate. Individuals with higher Body Mass Indexes have less supplement use, unhealthier diets and donot consume sufficient vegetables and fruits, all of which can affect decrease in folate levels. Furthermore, adiposity may affect folate absorption by intestinal epithelium.

Absorption and metabolism of isothiocyanates formed from broccoli glucosinolates: effects of BMI and daily consumption in a randomised clinical trial

Sulphoraphane originates from glucoraphanin in broccoli and is associated with anti-cancer effects. A preclinical study suggested that daily consumption of broccoli may increase the production of sulphoraphane and sulphoraphane metabolites available for absorption. The objective of this study was to determine whether daily broccoli consumption alters the absorption and metabolism of isothiocyanates derived from broccoli glucosinolates. We conducted a randomised cross-over human study (n 18) balanced for BMI and glutathione S-transferase μ 1 (GSTM1) genotype in which subjects consumed a control diet with no broccoli (NB) for 16 d or the same diet with 200 g of cooked broccoli and 20 g of raw daikon radish daily for 15 d (daily broccoli, DB) and 100 g of broccoli and 10 g of daikon radish on day 16. On day 17, all subjects consumed a meal of 200 g of broccoli and 20 g of daikon radish. Plasma and urine were collected for 24 h and analysed for sulphoraphane and metabolites of sulphoraphane and erucin by triple quadrupole tandem MS. For subjects with BMI >26 kg/m2 (median), plasma AUC and urinary excretion rates of total metabolites were higher on the NB diet than on the DB diet, whereas for subjects with BMI <26 kg/m2, plasma AUC and urinary excretion rates were higher on the DB diet than on the NB diet. Daily consumption of broccoli interacted with BMI but not GSTM1 genotype to affect plasma concentrations and urinary excretion of glucosinolate-derived compounds believed to confer protection against cancer. This trial was registered as NCT02346812.

B-vitamins and body composition: integrating observational and experimental evidence from the B-PROOF study

Purpose

Higher folate and vitamin-B12 have been linked to lower risk of overweight. However, whether this is a causal effect of these B-vitamins on obesity risk remains unclear and evidence in older individuals is scarce. This study aimed to assess the role of B-vitamin supplementation and levels on body composition in older individuals.

Methods

A double-blind, randomized controlled trial in 2919 participants aged ≥ 65 years with elevated homocysteine levels. The intervention comprised a 2-year supplementation with a combination of folic acid (400 µg) and vitamin B12 (500 µg), or with placebo. Serum folate, vitamin-B12, active vitamin-B12 (HoloTC), methylmalonic acid (MMA), and anthropometrics were measured at baseline and after 2 years of follow-up. Dietary intake of folate and vitamin-B12 was measured at baseline in a subsample (n = 603) using a validated food-frequency questionnaire. Fat mass index (FMI) and fat-free mass index (FFMI) were assessed with Dual Energy X-ray absorptiometry (DXA).

Results

Cross-sectional analyses showed that a 1 nmol/L higher serum folate was associated with a 0.021 kg/m² lower BMI (95% CI − 0.039; − 0.004). Higher HoloTC (per pmol/L log-transformed) was associated with a 0.955 kg/m² higher FMI (95% CI 0.262; 1.647), and higher MMA (per μgmol/L) was associated with a 1.108 kg/m² lower FMI (95% CI − 1.899; − 0.316). However, random allocation of B-vitamins did not have a significant effect on changes in BMI, FMI or FFMI during 2 years of intervention.

Conclusions

Although observational data suggested that folate and vitamin B12 status are associated with body composition, random allocation of a supplement with both B-vitamins combined versus placebo did not confirm an effect on BMI or body composition.

Electronic supplementary material

The online version of this article (10.1007/s00394-019-01985-8) contains supplementary material, which is available to authorized users.

Sex-Specific Associations of Blood-Based Nutrient Profiling With Body Composition in the Elderly

The intake of adequate amounts and types of nutrients is key for sustaining health and a good quality of life, particularly in the elderly population. There is considerable evidence suggesting that physiological changes related to age and sex modify nutritional needs, and this may be related to age-associated changes in body composition (BC), specifically in lean and fat body mass. However, there is a clear lack of understanding about the association of nutrients in blood and BC parameters in the elderly. This study investigated the relationships among blood nutrients (amino acids, fatty acids, major elements, trace-elements, and vitamins), BC and nutrient intake in a population of 176 healthy male and female Italian adults between the ages of 65 and 79 years. 89 blood markers, 77 BC parameters and dietary intake were evaluated. Multivariate data analysis was applied to infer relationships between datasets. As expected, the major variability between BC and the blood nutrient profile (BNP) observed was related to sex. Aside from clear sex-specific differences in BC, female subjects had higher BNP levels of copper, copper-to-zinc ratio, phosphorous and holotranscobalamin II and lower concentrations of branched-chain amino acids (BCAAs) and proline. Fat mass, percentage of fat mass, percentage of lean mass and the skeletal muscle index (SMI) correlated the most with BNP in both sexes. Our data showed positive correlations in male subjects among ethanolamine, glycine, albumin, and sulfur with SMI, while palmitoleic acid and oleic acid exhibited negative correlations. This differed in female subjects, where SMI was positively associated with albumin, folic acid and sulfur, while CRP, proline and cis-8,11,14-eicosatrienoic acid were negatively correlated. We investigated the influence of diet on the observed BNP and BC correlations. Intriguingly, most of the components of the BNP, except for folate, did not exhibit a correlation with nutrient intake data. An understanding of the physiological and biochemical processes underpinning the observed sex-specific correlations between BNP and BC could help in identifying nutritional strategies to manage BC-changes in aging. This would contribute to a deeper understanding of aging-associated nutritional needs with the aim of helping the elderly population to maintain metabolic health.

Targeted metabolomics to understand the association between arsenic metabolism and diabetes-related outcomes: Preliminary evidence from the Strong Heart Family Study

BACKGROUND

Inorganic arsenic exposure is ubiquitous and both exposure and inter-individual differences in its metabolism have been associated with cardiometabolic risk. A more efficient arsenic metabolism profile (lower MMA%, higher DMA%) has been associated with reduced risk for arsenic-related health outcomes. This profile, however, has also been associated with increased risk for diabetes-related outcomes.

OBJECTIVES

The mechanism behind these conflicting associations is unclear; we hypothesized the one-carbon metabolism (OCM) pathway may play a role.

METHODS

We evaluated the influence of OCM on the relationship between arsenic metabolism and diabetes-related outcomes (HOMA2-IR, waist circumference, fasting plasma glucose) using metabolomic data from an OCM-specific and P180 metabolite panel measured in plasma, arsenic metabolism measured in urine, and HOMA2-IR and FPG measured in fasting plasma. Samples were drawn from baseline visits (2001-2003) in 59 participants from the Strong Heart Family Study, a family-based cohort study of American Indians aged ≥14 years from Arizona, Oklahoma, and North/South Dakota.

RESULTS

In unadjusted analyses, a 5% increase in DMA% was associated with higher HOMA2-IR (geometric mean ratio (GMR)= 1.13 (95% CI: 1.03, 1.25)) and waist circumference (mean difference=3.66 (0.95, 6.38). MMA% was significantly associated with lower HOMA2-IR and waist circumference. After adjustment for OCM-related metabolites (SAM, SAH, cysteine, glutamate, lysophosphatidylcholine 18.2, and three phosphatidlycholines), associations were attenuated and no longer significant.

CONCLUSIONS

These preliminary results indicate that the association of lower MMA% and higher DMA% with diabetes-related outcomes may be influenced by OCM status, either through confounding, reverse causality, or mediation.

Arsenic, one carbon metabolism and diabetes-related outcomes in the Strong Heart Family Study

BACKGROUND

Inorganic arsenic exposure and inter-individual differences in its metabolism have been associated with cardiometabolic risk. A more efficient arsenic metabolism profile (lower MMA%, higher DMA%) has been associated with reduced risk for arsenic-related health outcomes; however, this profile has also been associated with increased risk for diabetes-related outcomes. The mechanism behind these contrasting associations is equivocal; we hypothesized one carbon metabolism (OCM) may play a role.

METHODS

We evaluated the association between OCM-related variables (nutrient intake and genetic variants) and both arsenic metabolism biomarkers (iAs%, MMA% and DMA%) and diabetes-related outcomes (metabolic syndrome, diabetes, HOMA2-IR and waist circumference) in 935 participants free of prevalent diabetes and metabolic syndrome from the Strong Heart Family Study, a family-based prospective cohort comprised of American Indian tribal members aged 14+ years.

RESULTS

Of the 935 participants free of both diabetes and metabolic syndrome at baseline, 279 (29.8%) developed metabolic syndrome over a median of 5.3 years of follow-up and of the 1458 participants free of diabetes at baseline, 167 (11.3%) developed diabetes over follow-up. OCM nutrients were not associated with arsenic metabolism, however, higher vitamin B₆ was associated with diabetes-related outcomes (higher HOMA2-IR and increased risk for diabetes and metabolic syndrome). A polymorphism in an OCM-related gene, methionine synthase (MTR), was associated with both higher MMA% (β = 2.57, 95% CI: 0.22, 4.92) and lower HOMA2-IR (GMR = 0.79, 95% CI = 0.66, 0.93 per 5 years of follow-up). Adjustment for OCM variables did not affect previously reported associations between arsenic metabolism and diabetes-related outcomes; however, the association between the MTR variant and diabetes-related outcomes were attenuated after adjustment for arsenic metabolism.

CONCLUSIONS

Our findings suggest MMA% may be a partial mediator in the association between OCM and diabetes-related outcomes. Additional mediation analyses with longer follow-up period are needed to confirm this finding. Further research is needed to determine whether excess B vitamin intake is associated with increased risk for diabetes-related outcomes.

Review article: drug-induced liver injury in the context of nonalcoholic fatty liver disease - a physiopathological and clinical integrated view

BACKGROUND

Nonalcoholic fatty disease (NAFLD) is the most common liver disease, since it is strongly associated with obesity and metabolic syndrome pandemics. NAFLD may affect drug disposal and has common pathophysiological mechanisms with drug-induced liver injury (DILI); this may predispose to hepatoxicity induced by certain drugs that share these pathophysiological mechanisms. In addition, drugs may trigger fatty liver and inflammation per se by mimicking NAFLD pathophysiological mechanisms.

AIMS

To provide a comprehensive update on (a) potential mechanisms whereby certain drugs can be more hepatotoxic in NAFLD patients, (b) the steatogenic effects of drugs, and (c) the mechanism involved in drug-induced steatohepatitis (DISH).

METHODS

A language- and date-unrestricted Medline literature search was conducted to identify pertinent basic and clinical studies on the topic.

RESULTS

Drugs can induce macrovesicular steatosis by mimicking NAFLD pathogenic factors, including insulin resistance and imbalance between fat gain and loss. Other forms of hepatic fat accumulation exist, such as microvesicular steatosis and phospholipidosis, and are mostly associated with acute mitochondrial dysfunction and defective lipophagy, respectively. Drug-induced mitochondrial dysfunction is also commonly involved in DISH. Patients with pre-existing NAFLD may be at higher risk of DILI induced by certain drugs, and polypharmacy in obese individuals to treat their comorbidities may be a contributing factor.

CONCLUSIONS

The relationship between DILI and NAFLD may be reciprocal: drugs can cause NAFLD by acting as steatogenic factors, and pre-existing NAFLD could be a predisposing condition for certain drugs to cause DILI. Polypharmacy associated with obesity might potentiate the association between this condition and DILI.

High-fat diet consumption reduces hepatic folate transporter expression via nuclear respiratory factor-1

Folate is an essential micronutrient for biological function. The liver, a primary organ for folate metabolism and storage, plays an important role in folate homeostasis. Proton-coupled folate transporter (PCFT) and reduced folate carrier (RFC) are the major folate transporters responsible for folate uptake at basolateral membrane of hepatocytes. Low serum folate levels are frequently associated with obesity. We investigated the mechanism that regulated folate status in a mouse model with diet-induced obesity. Mice (C57BL/6J) were fed a high-fat diet (60% kcal fat) for 8 weeks. Mice displayed increased hepatic lipid accumulation and decreased folate levels in the liver and serum compared to mice fed a normal chow diet (10% kcal fat). High-fat diet-fed mice had low expression of PCFT and RFC and decreased nuclear respiratory factor-1 (NRF-1)/DNA-binding activity. Treatment with NRF-1 siRNA or palmitic acid reduced folate transporter expression in hepatocytes. Inhibition of NRF-1 mediated folate transporter expression significantly reduced intracellular folate levels. These results suggest that chronic consumption of high-fat diets impairs folate transporter expression via NRF-1-dependent mechanism, leading to reduced hepatic folate storage. Understanding the regulation of folate homeostasis in obesity may have an important implication in current guideline of folate intake. KEY MESSAGES: Serum and liver folate levels are decreased in diet-induced obese mice. Chronic high-fat diet consumption impairs expression of hepatic PCFT and RFC. NRF-1 regulates hepatic folate transporters expression and folate levels.

Effect of low energy diet for eight weeks to adults with overweight or obesity on folate, retinol, vitamin B12, D and E status and the degree of inflammation: a post hoc analysis of a randomized intervention trial

Background

Obesity is associated with vitamin insufficiency and low grade inflammation. The purpose of this study was to investigate the effect of weight loss on folate, retinol, vitamin B₁₂, D and E status and the degree of inflammation.

Methods

Out of 110, 85 individuals (75% women) aged 39 ± 11 years with a mean ± SD BMI of 33 ± 4 kg/m², completed an eight-week low energy diet (LED). Serum concentration of folate, retinol, B₁₂, D and E and C-reactive protein and homocysteine (Hcy) were measured at baseline and at end of the LED.

Results

At baseline, 8% of the participants were deficient in folate, 13% in vitamin B₁₂, 2% in retinol, 28% in vitamin D (72% were insufficient in vitamin D), and none were deficient in vitamin E. At baseline, BMI was inversely associated with retinol (P < 0.05) as was total and abdominal fat percentage with folate (P < 0.05); further BMI and measures of adiposity were positively associated with CRP (P < 0.01) and Hcy (P < 0.05). Homocysteine was inversely associated with all vitamins but retinol (P < 0.001). After the LED, the participants lost a mean [95% confidence intervals] of 12.3 [− 13.1,-11.6] kg. The serum concentration of folate, vitamin B₁₂ and D were increased (P < 0.001) after the LED whereas the concentration of retinol and vitamin E were reduced (P < 0.001).

Conclusion

Eight-weeks LED resulted in 13% weight loss and an increase in the serum concentrations of folate, vitamin B₁₂ and D. Baseline adiposity was inversely associated with folate and retinol, and positively associated with markers of inflammation.

Trial registration

Ethical Committee of Copenhagen as no. H-4-2013-135, NCT01561131.

Association between vitamin deficiency and metabolic disorders related to obesity

Inappropriate food behavior contributes to obesity and leads to vitamin deficiency. This review discusses the nutritional status of water- and fat-soluble vitamins in obese subjects. We verified that most vitamins are deficient in obese individuals, especially the fat-soluble vitamins, folic acid, vitamin B₁₂ and vitamin C. However, some vitamins have been less evaluated in cases of obesity. The adipose tissue is considered a metabolic and endocrine organ, which in excess leads to changes in body homeostasis, as well as vitamin deficiency which can aggravate the pathological state. Therefore, the evaluation of vitamin status is of fundamental importance in obese individuals.

Association of low dietary folate intake with lower CAMKK2 gene methylation, adiposity, and insulin resistance in obese subjects

Folate deficiency has been putatively implicated in the onset of diverse metabolic abnormalities, including insulin resistance, by altering epigenetic processes on key regulatory genes. The calcium/calmodulin-dependent protein kinase kinase 2 (CAMKK2) is involved in the regulation of critical metabolic processes such as adiposity and glucose homeostasis. This study hypothesized associations between low folate intakes and lower methylation levels of the CAMKK2 gene, with the presence of metabolic alterations in subjects with obesity. A cross-sectional ancillary study was conducted in obese subjects (n=47) from the RESMENA study (Spain). Fat mass was measured by dual-energy x-ray absorptiometry. Dietary intake and metabolic profile were assessed by validated methods. DNA methylation and gene expression in peripheral white blood cells were analyzed by microarray approaches. A total of 51 cytosine-phosphate-guanine sites were associated with folate intake (false discovery rate values < 0.0001), including one located in the 5' untranslated region of the CAMKK2 gene (Illumina ID, cg16942632), which was selected and separately analyzed. Subjects with total folate intake lower than 300μg/d showed more fat mass (especially trunk fat), as well as statistically higher levels of glucose, insulin, homeostatic model assessment-insulin resistance (HOMA-IR) index, cortisol, and plasminogen activator inhibitor-1 than those consuming at least or more than 300μg/d. Of note, folate deficiency was related to lower CAMKK2 methylation. Interestingly, CAMKK2 methylation negatively correlated with the HOMA-IR index. Furthermore, CAMKK2 expression directly correlated with HOMA-IR values. In summary, this study suggests associations between low folate intakes, lower CAMKK2 gene methylation, and insulin resistance in obese individuals.

The effect of obesity and repeated exposure on pharmacokinetic response to grape polyphenols in humans

SCOPE

Evidence suggests that dietary pattern may affect polyphenol absorption and/or metabolism. Further, obesity is associated with lower circulating nutrients, though the reason is unclear. We investigated the pharmacokinetic (PK) response of polyphenols in obese/overweight versus lean individuals before and after repeated dosing of grape polyphenols.

METHODS AND RESULTS

A pilot study was conducted in which PK challenges were administered before and after 10 days of repeated dosing with polyphenols. Volunteers (6 lean, 6 overweight/obese) consumed resveratrol, grape seed extract, and grape juice (2125 mg total polyphenols) daily. On days 1 and 11, blood samples were collected for 6 h after the polyphenol dose and analyzed for deconjugated catechin, epicatechin, resveratrol, and quercetin. Area under the plasma polyphenol mass by time curves (AUCs) were greater for catechin, epicatechin, and quercetin on day 11 versus day 1 for low BMI individuals (p = 0.039) but not high BMI individuals. Further, AUCs were greater for epicatechin and resveratrol for low versus high BMI individuals (p = 0.041), with a similar trend for catechin (p = 0.065), on day 11 but not day 1.

CONCLUSION

These results suggest that that obesity and repeated exposure may modify polyphenol absorption and/or metabolism in humans.

Role of folate in nonalcoholic fatty liver disease

Nonalcoholic fatty liver disease (NAFLD) is a spectrum of chronic liver conditions that are characterized by steatosis, inflammation, fibrosis, and liver injury. The global prevalence of NAFLD is rapidly increasing in proportion to the rising incidence of obesity and type 2 diabetes. Because NAFLD is a multifaceted disorder with many underlying metabolic abnormalities, currently, there is no pharmacological agent that is therapeutically approved for the treatment of this disease. Folate is a water-soluble B vitamin that plays an essential role in one-carbon transfer reactions involved in nucleic acid biosynthesis, methylation reactions, and sulfur-containing amino acid metabolism. The liver is the primary organ responsible for storage and metabolism of folates. Low serum folate levels have been observed in patients with obesity and diabetes. It has been reported that a low level of endogenous folates in rodents perturbs folate-dependent one-carbon metabolism, and may be associated with development of metabolic diseases such as NAFLD. This review highlights the biological role of folate in the progression of NAFLD and its associated metabolic complications including obesity and type 2 diabetes. Understanding the role of folate in metabolic disease may position this vitamin as a potential therapeutic for NAFLD.

Serum and red-blood-cell folate demonstrate differential associations with BMI in pregnant women

Objective

To examine the association between BMI and folate concentrations in serum and red blood cells (RBC) in pregnant women.

Design

A cross-sectional comparison of folate concentrations in serum and RBC sampled simultaneously from the same individual.

Setting

The Ottawa Hospital and Kingston General Hospital, Ontario, Canada.

Subjects

Pregnant women recruited between 12 and 20 weeks of gestation.

Results

A total of 869 pregnant women recruited from April 2008 to April 2009 were included in the final analysis. Serum folate was inversely associated and RBC folate positively associated with BMI, after adjusting for folic acid supplementation, age, gestational age at blood sample collection, race, maternal education, annual income, smoking and MTHFR 677C→T genotype. In stratified analyses, this differential association was significant in women with the MTHFR CC variant. In women with the CT and TT variants, the differential associations were in the same direction but not significant. Folic acid supplementation during pregnancy did not alter the differential association of BMI with serum and RBC folate concentration. This indicates that the current RBC folate cut-off approach for assessing risk of neural tube defects in obese women may be limited.

Conclusions

BMI is inversely associated with serum folate and positively associated with RBC folate in pregnant women, especially for those with the MTHFR CC variant.

Folic acid supplementation during high-fat diet feeding restores AMPK activation via an AMP-LKB1-dependent mechanism

AMPK is an endogenous energy sensor that regulates lipid and carbohydrate metabolism. Nonalcoholic fatty liver disease (NAFLD) is regarded as a hepatic manifestation of metabolic syndrome with impaired lipid and glucose metabolism and increased oxidative stress. Our recent study showed that folic acid supplementation attenuated hepatic oxidative stress and lipid accumulation in high-fat diet-fed mice. The aim of the present study was to investigate the effect of folic acid on hepatic AMPK during high-fat diet feeding and the mechanisms involved. Male C57BL/6J mice were fed a control diet (10% kcal fat), a high-fat diet (60% kcal fat), or a high-fat diet supplemented with folic acid (26 mg/kg diet) for 5 wk. Mice fed a high-fat diet exhibited hyperglycemia, hepatic cholesterol accumulation, and reduced hepatic AMPK phosphorylation. Folic acid supplementation restored AMPK phosphorylation (activation) and reduced blood glucose and hepatic cholesterol levels. Activation of AMPK by folic acid was mediated through an elevation of its allosteric activator AMP and activation of its upstream kinase, namely, liver kinase B1 (LKB1) in the liver. Consistent with in vivo findings, 5-methyltetrahydrofolate (bioactive form of folate) restored phosphorylation (activation) of both AMPK and LKB1 in palmitic acid-treated HepG2 cells. Activation of AMPK by folic acid might be responsible for AMPK-dependent phosphorylation of HMG-CoA reductase, leading to reduced hepatic cholesterol synthesis during high-fat diet feeding. These results suggest that folic acid supplementation may improve cholesterol and glucose metabolism by restoration of AMPK activation in the liver.

DNA Methylation Variants at HIF3A Locus, B-Vitamin Intake, and Long-term Weight Change: Gene-Diet Interactions in Two U.S. Cohorts

The first epigenome-wide association study of BMI identified DNA methylation at an HIF3A locus associated with BMI. We tested the hypothesis that DNA methylation variants are associated with BMI according to intake of B vitamins. In two large cohorts, we found significant interactions between the DNA methylation-associated HIF3A single nucleotide polymorphism (SNP) rs3826795 and intake of B vitamins on 10-year changes in BMI. The association between rs3826795 and BMI changes consistently increased across the tertiles of total vitamin B2 and B12 intake (all P for interaction <0.01). The differences in the BMI changes per increment of minor allele were -0.10 (SE 0.06), -0.01 (SE 0.06), and 0.12 (SE 0.07) within subgroups defined by increasing tertiles of total vitamin B2 intake and -0.10 (SE 0.06), -0.01 (SE 0.06), and 0.10 (SE 0.07) within subgroups defined by increasing tertiles of total vitamin B12 intake. In two independent cohorts, a DNA methylation variant in HIF3A was associated with BMI changes through interactions with total or supplemental vitamin B2, vitamin B12, and folate. These findings suggest a potential causal relation between DNA methylation and adiposity.

Obesity is associated with increased red blood cell folate despite lower dietary intakes and serum concentrations

BACKGROUND

Folates are essential cofactors in metabolic pathways that facilitate biological methylation and nucleotide synthesis, and therefore have widespread effects on health and diseases. Although obesity is prevalent worldwide, few studies have investigated how obesity interacts with folate status.

OBJECTIVE

Based on data from the NHANES, this study aims to examine the association between body mass index (BMI) and obesity-related metabolic factors with blood folate status.

METHODS

A nationally representative sample of 3767 adults from the NHANES (2003-2006) was used as the study population. Regression analyses, with and without adjustment for demographic factors and dietary intakes, were performed to examine associations between BMI and metabolic factors with serum and RBC folate.

RESULTS

The results indicate serum folate concentrations were lower in obese groups compared to the desirable BMI and overweight categories, paralleling lower intakes in this group. In contrast, RBC folate increased incrementally with BMI. Regression analyses demonstrated an inverse relation between BMI and serum folate but a positive relation for RBC folate (P < 0.01). Waist circumference, serum triglycerides, and fasting plasma glucose each displayed significant positive relations with RBC folate (P < 0.01), although relations with serum folate were not significant and consistent.

CONCLUSIONS

In summary, obesity is associated with decreased serum folate, which parallels decreased folate intakes. In contrast, obesity is positively associated with RBC folate. Therefore, RBC folate, in addition to serum folate, should also be considered as a critical biomarker for folate status, especially in the obese population. Future research is needed to understand how obesity differentially alters serum and RBC folate status because they are associated with a variety of medical complications.

Low paternal dietary folate alters the mouse sperm epigenome and is associated with negative pregnancy outcomes

Epidemiological studies suggest that a father's diet can influence offspring health. A proposed mechanism for paternal transmission of environmental information is via the sperm epigenome. The epigenome includes heritable information such as DNA methylation. We hypothesize that the dietary supply of methyl donors will alter epigenetic reprogramming in sperm. Here we feed male mice either a folate-deficient or folate-sufficient diet throughout life. Paternal folate deficiency is associated with increased birth defects in the offspring, which include craniofacial and musculoskeletal malformations. Genome-wide DNA methylation analysis and the subsequent functional analysis identify differential methylation in sperm of genes implicated in development, chronic diseases such as cancer, diabetes, autism and schizophrenia. While >300 genes are differentially expressed in offspring placenta, only two correspond to genes with differential methylation in sperm. This model suggests epigenetic transmission may involve sperm histone H3 methylation or DNA methylation and that adequate paternal dietary folate is essential for offspring health.

Novel insights on interactions between folate and lipid metabolism

Folate is an essential B vitamin required for the maintenance of AdoMet-dependent methylation. The liver is responsible for many methylation reactions that are used for post-translational modification of proteins, methylation of DNA, and the synthesis of hormones, creatine, carnitine, and phosphatidylcholine. Conditions where methylation capacity is compromised, including folate deficiency, are associated with impaired phosphatidylcholine synthesis resulting in non-alcoholic fatty liver disease and steatohepatitis. In addition, folate intake and folate status have been associated with changes in the expression of genes involved in lipid metabolism, obesity, and metabolic syndrome. In this review, we provide insight on the relationship between folate and lipid metabolism, and an outlook for the future of lipid-related folate research.

Maternal body mass index and the association between folic acid supplements and neural tube defects

AIM

To study the influence of maternal body mass index (BMI) on the association between folic acid supplementation and neural tube defects (NTDs) risk in offspring.

METHODS

A hospital-based, case-control study was conducted between 2006 and 2008 on 459 mothers with NTDs-affected births and 459 mothers without NTDs-affected births. Logistic regression models examined the associations between folic acid supplementation and the NTDs risk in offspring for all mothers, underweight/normal weight mothers (BMI<24.0) and overweight/obese mothers (BMI ≥24.0). The effects were evaluated by adjusted odds ratio (AOR) and 95% confidence intervals (CIs) with SAS 9.1.3 software.

RESULTS

The overall AOR for periconceptional folic acid supplementation was 0.315 (95% CI = 0.172-0.577) when compared with no supplements. Stratified by maternal BMI, the AOR for periconceptional folic acid supplementation in overweight/obese mothers was greater than in underweight/normal weight mothers (0.646 vs. 0.208). The AOR for folic acid supplementation within 3 months before conception was 0.711 (95% CI = 0.323-1.563) in all mothers. Stratified by maternal BMI, the AOR for folic acid supplementation within 3 months before conception in overweight/obese mothers was greater than in underweight/normal weight mothers (0.658 vs. 0.527).

CONCLUSION

The association between folic acid supplementation and the reduced NTDs risk was weaker in overweight/obese mothers (BMI ≥24.0) than in underweight/normal weight mothers (BMI <24.0).

A novel mouse model for genetic variation in 10-formyltetrahydrofolate synthetase exhibits disturbed purine synthesis with impacts on pregnancy and embryonic development

Genetic variants in one-carbon folate metabolism have been identified as risk factors for disease because they may impair the production or use of one-carbon folates required for nucleotide synthesis and methylation. p.R653Q (1958G>A) is a single-nucleotide polymorphism (SNP) in the 10-formyltetrahydrofolate (formylTHF) synthetase domain of the trifunctional enzyme MTHFD1; this domain produces the formylTHF which is required for the de novo synthesis of purines. Approximately 20% of Caucasians are homozygous for the Q allele. MTHFD1 p.R653Q has been proposed as a risk factor for neural tube defects (NTDs), congenital heart defects (CHDs) and pregnancy losses. We have generated a novel mouse model in which the MTHFD1 synthetase activity is inactivated without affecting protein expression or the other activities of this enzyme. Complete loss of synthetase activity (Mthfd1S(-/-)) is incompatible with life; embryos die shortly after 10.5 days gestation, and are developmentally delayed or abnormal. The proportion of 10-formylTHF in the plasma and liver of Mthfd1S(+/-) mice is reduced (P < 0.05), and de novo purine synthesis is impaired in Mthfd1S(+/-) mouse embryonic fibroblasts (MEFs, P < 0.005). Female Mthfd1S(+/-) mice had decreased neutrophil counts (P < 0.05) during pregnancy and increased incidence of developmental defects in embryos (P = 0.052). These findings suggest that synthetase deficiency may lead to pregnancy complications through decreased purine synthesis and reduced cellular proliferation. Additional investigation of the impact of synthetase polymorphisms on human pregnancy is warranted.

Single nucleotide polymorphisms in CETP, SLC46A1, SLC19A1, CD36, BCMO1, APOA5, and ABCA1 are significant predictors of plasma HDL in healthy adults

Background

In a marker-trait association study we estimated the statistical significance of 65 single nucleotide polymorphisms (SNP) in 23 candidate genes on HDL levels of two independent Caucasian populations. Each population consisted of men and women and their HDL levels were adjusted for gender and body weight. We used a linear regression model. Selected genes corresponded to folate metabolism, vitamins B-12, A, and E, and cholesterol pathways or lipid metabolism.

Methods

Extracted DNA from both the Sacramento and Beltsville populations was analyzed using an allele discrimination assay with a MALDI-TOF mass spectrometry platform. The adjusted phenotype, y, was HDL levels adjusted for gender and body weight only statistical analyses were performed using the genotype association and regression modules from the SNP Variation Suite v7.

Results

Statistically significant SNP (where P values were adjusted for false discovery rate) included: CETP (rs7499892 and rs5882); SLC46A1 (rs37514694; rs739439); SLC19A1 (rs3788199); CD36 (rs3211956); BCMO1 (rs6564851), APOA5 (rs662799), and ABCA1 (rs4149267). Many prior association trends of the SNP with HDL were replicated in our cross-validation study. Significantly, the association of SNP in folate transporters (SLC46A1 rs37514694 and rs739439; SLC19A1 rs3788199) with HDL was identified in our study.

Conclusions

Given recent literature on the role of niacin in the biogenesis of HDL, focus on status and metabolism of B-vitamins and metabolites of eccentric cleavage of β-carotene with lipid metabolism is exciting for future study.

Obesity affects short-term folate pharmacokinetics in women of childbearing age

Maternal folate status and body mass index (BMI) are independent risk factors for neural tube defects (NTD). Population-based studies have identified an inverse association between serum folate and BMI, after adjusting for intake. The objective of this intervention study was to compare the relationship between BMI and the short-term pharmacokinetic response to an oral dose of folic acid. Healthy obese (BMI 30.0 kg m(-2); n=16) and normal-weight (BMI 18.5-24.9 kg m(-2); n=16) women of childbearing age (18-35 years) were administered a single oral dose of folic acid (400 μg). Blood samples were collected over a 10-h period to evaluate the serum folate response. Fasting baseline serum folate was lower in the obese group (P=0.005); in contrast, red blood cell folate was higher (P=0.05). Area-under-the-curve for the absorption phase (0-3 h) and peak serum folate concentrations were lower in obese versus normal-weight women (P<0.005). Overall serum folate response (0-10 h) was lower in obese versus normal-weight women (repeated-measures ANOVA, P=0.001). Data suggest body distribution of folate is significantly affected by obesity, and, should pregnancy occur, may reduce the amount of folate available to the developing embryo. These findings provide additional support for a BMI-adjusted folic acid intake recommendation for NTD risk reduction.

Pre-pregnancy obesity and maternal nutritional biomarker status during pregnancy: a factor analysis

OBJECTIVE

Pre-pregnancy obesity has been associated with adverse birth outcomes. Poor essential fatty acid (EFA) and micronutrient status during pregnancy may contribute to these associations. We assessed the associations between pre-pregnancy BMI and nutritional patterns of maternal micronutrient and EFA status during mid-pregnancy.

DESIGN

A cross-sectional analysis from a prospective cohort study. Women provided non-fasting blood samples at ≥ 20 weeks’ gestation that were assayed for red cell EFA; plasma folate, homocysteine and ascorbic acid; and serum retinol, 25-hydroxyvitamin D, a-tocopherol, soluble transferrin receptors and carotenoids. These nutritional biomarkers were employed in a factor analysis and three patterns were derived: EFA, Micronutrients and Carotenoids.

SETTING

The Antidepressant Use During Pregnancy Study, Pittsburgh, PA, USA.

SUBJECTS

Pregnant women (n 129).

RESULTS

After adjustment for parity, race/ethnicity and age, obese pregnant women were 3.0 (95% CI 1.1, 7.7) times more likely to be in the lowest tertile of the EFA pattern and 4.5 (95% CI 1.7, 12.3) times more likely to be in the lowest tertile of the Carotenoid pattern compared with their lean counterparts. We found no association between pre-pregnancy obesity and the Micronutrient pattern after confounder adjustment.

CONCLUSIONS

Our results suggest that obese pregnant women have diminished EFA and carotenoid concentrations.