Association of B vitamin intake and total homocysteine levels with all-cause and cause-specific mortality in central obesity

OBJECTIVES

Future primary prevention strategies may benefit from understanding the connection between mortality in individuals with central obesity and modifiable lifestyle factors like dietary intake. This study sought to determine whether there was a separate relationship between folate, vitamin B6, and vitamin B12 intake and all-cause and cause-specific mortality in the US population with central obesity.

METHODS

The study analyzed data from the National Health and Nutrition Examination Survey between 1999 and 2016. Using the Cox proportional hazards model, the association between dietary intake of B vitamins and all-cause and cause-specific mortality was examined. A total of 7718 adults with central obesity were enrolled, with a mean age of 49.87 (SD = 0.25) y at baseline.

RESULTS

Folate intake was independently associated with a decreased incidence of all-cause mortality (adjusted hazard ratio = 0.71; 95% CI, 0.58-0.87). Furthermore, higher intake of vitamin B6 and vitamin B12 was inversely correlated with cardiovascular disease mortality (adjusted hazard ratio = 0.63; 95% CI, 0.40-0.98; and adjusted hazard ratio = 0.44; 95% CI, 0.29-0.65, respectively) and the finding reveal an interaction between homocysteine and vitamin B12 and folate on All-cause mortality CONCLUSIONS: The findings of this study suggest that vitamin B12 and folate intake may be protective factors in individuals with central obesity. It is important to consider both their total homocysteine level and body mass index in conjunction with these nutrients. Further research is needed to validate these findings.

Perinatal folate levels do not influence tumor latency or multiplicity in a model of NF1 associated plexiform-like neurofibromas

OBJECTIVE

In epidemiological and experimental research, high folic acid intake has been demonstrated to accelerate tumor development among populations with genetic and/or molecular susceptibility to cancer. Neurofibromatosis type 1 (NF1) is a common autosomal dominant disorder predisposing affected individuals to tumorigenesis, including benign plexiform neurofibromas; however, understanding of factors associated with tumor risk in NF1 patients is limited. Therefore, we investigated whether pregestational folic acid intake modified plexiform-like peripheral nerve sheath tumor risk in a transgenic NF1 murine model.

RESULTS

We observed no significant differences in overall survival according to folate group. Relative to controls (180 days), median survival did not statistically differ in deficient (174 days, P = 0.56) or supplemented (177 days, P = 0.13) folate groups. Dietary folate intake was positively associated with RBC folate levels at weaning, (P = 0.023, 0.0096, and 0.0006 for deficient vs. control, control vs. supplemented, and deficient vs. supplemented groups, respectively). Dorsal root ganglia (DRG), brachial plexi, and sciatic nerves were assessed according to folate group. Mice in the folate deficient group had significantly more enlarged DRG relative to controls (P = 0.044), but no other groups statistically differed. No significant differences for brachial plexi or sciatic nerve enlargement were observed according to folate status.

Association between dietary folate intake and cognitive impairment in older US adults: National Health and Nutrition Examination Survey

OBJECTIVE

To determine the association between dietary folate intake and low cognitive performance in older adults.

METHODS

In this cross-sectional observational study, 2011-2014 data from the 2010 National Health and Nutrition Examination Survey, including 2,524 adults aged 60 years and older, included 24-hour dietary intakes. Total folic acid intake was calculated as the sum of folic acid supplements and dietary folic acid. Cognitive function was assessed using three tests. The association between folate intake and cognitive function was assessed using a multivariate conditional logistic regression model.

RESULTS

2524 participants from two survey cycles (2011-2014) in the NHANES aged 60 years and over. In the multivariate logistic regression, the OR of developing folate was 0.96 (95% CI: 0.94∼0.98) in participants with Z test. Folate intake was negatively associated with cognitive function. Compared with Q1, Q4(≥ 616.3mg/day) in the AFT and DSST tests reduced the risk of cognitive impairment by 31% (OR = 0.69, 95% CI: 0.52-0.93) and 44% (OR = 0.56). 95% confidence interval: 0.44-0.7). In the comprehensive evaluation of IR and AFT scores, the association between dietary folate intake and low cognitive performance in US adults is linear. We also found a significant interaction between gender and cognitive ability (P value for the interaction was 0.021).

CONCLUSIONS

Dietary intake of folic acid may be inversely associated with cognitive impairment. The DSST study found an L-shaped association between dietary folate intake and cognitive decline in US adults, with an inflection point of approximately 510,383 mg/day.

Association of folate intake with cardiovascular-disease mortality and all-cause mortality among people at high risk of cardiovascular-disease

BACKGROUND & AIMS

Due to the beneficial effect of folate on cardiovascular disease (CVD), folic acid supplementation is a more common practice among people at high-risk of CVD. However, long-term prospective investigations regarding the association of folate-intake with CVD-mortality and all-cause mortality among this specific population are still lacking. Therefore, this study aims to assess the association of folate-intake with CVD-mortality and all-cause mortality.

METHODS

A total of 14,234 participants at high-risk of CVD were enrolled. Total folate equivalent (TFE), dietary folate equivalent (DFE), food folate, folic acid in fortified food, folic acid supplements, serum folate and red blood cell (RBC) folate were measured. The main outcome measures were CVD-mortality and all-cause mortality from baseline until 31 December 2015.

RESULTS

During the 98,890 person-year follow-up, 2036 deaths including 682 deaths due to CVD were documented. After multivariate adjustment, a J shaped association was found: modest intake of TFE and DFE was associated with lower risk of CVD-mortality and all-cause mortality, whereas higher intake did not persistently reduce these risks. Compared to the participants without folic acid supplementation matched 28-covariates using propensity score, folic acid supplementation was associated with higher risk of CVD-mortality (HR:1.44, 95%CI:1.06-1.97, P = 0.022) and all-cause mortality (HR:1.28,95%CI:1.09-1.51, P = 0.003). The levels of serum-folate and RBC-folate in participants with folic acid supplementation were significantly greater than participants without folic acid supplementation (41.8 nmol/l vs. 64.2 nmol/l, P < 0.001 for serum-folate; 1201 nmol/l vs. 1608 nmol/l, P < 0.001 for RBC-folate). Compared with the lowest-quintile of serum-folate, the second-quintile was consistently associated with CVD-mortality (HR:0.72, 95%CI:0.53-0.99, P = 0.048) and all-cause mortality (HR:0.78, 95%CI:0.64-0.94, P = 0.013). Compared to the lowest-quintile of RBC-folate, the second-quintile was associated with lower all-cause mortality (HR:0.71,95%CI:0.56-0.90, P = 0.005), whereas the highest-quintile was associated with higher CVD-mortality (HR:1.40,95%CI:1.02-1.93, P = 0.030). The J shaped association of serum-folate and RBC-folate with CVD-mortality and all-cause mortality was also demonstrated, further supporting the results of TFE and propensity score analysis.

CONCLUSIONS

This study suggested the beneficial effects of modest folate-intake on the improvement of long-term survival, and emphasized the potentially deleterious effects of excess folic acid supplementation among US adults at high-risk of CVD.

Association of dietary intakes of vitamin B12, vitamin B6, folate, and methionine with the risk of esophageal cancer: the Japan Public Health Center-based (JPHC) prospective study

Background

B vitamins and methionine are essential substrates in the one-carbon metabolism pathway involved in DNA synthesis and methylation. They may have essential roles in cancer development. We aimed to evaluate the associations of dietary intakes of vitamin B12, vitamin B6, folate, and methionine with the risk of esophageal cancer (EC) using data from the Japan Public Health Center-based Prospective Study.

Methods

We included 87,053 Japanese individuals who completed a food frequency questionnaire and were followed up from 1995–1998 to 2013 and 2015. Hazard ratios (HRs) and 95% confidence intervals (CIs) were calculated by Cox proportional-hazard regression across quintiles of dietary intakes of B vitamins and methionine.

Results

After 1,456,678 person-years of follow-up, 427 EC cases were documented. The multivariable HR (95% CI) of incident EC in the highest versus lowest quintile of dietary intake of vitamin B12 was 1.75 (1.13–2.71; p-trend=0.01). Stratification analysis based on alcohol consumption showed that higher dietary intakes of vitamin B12 and methionine were associated with an increased risk of EC among never-drinkers; HRs (95% CIs) were 2.82 (1.18–6.74; p-trend=0.009; p-interaction=0.18) and 3.45 (1.32–9.06; p-trend=0.003; p-interaction 0.02) for vitamin B12 and methionine, respectively. Meanwhile, there was no association between vitamin B12 and methionine intake with the risk of EC among drinkers. There were no associations between dietary intake of folate or vitamin B6 and the risk of EC.

Conclusion

Dietary intake of vitamin B12 was positively associated with the risk of EC in the Japanese population.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08721-8.

Dietary and lifestyle predictors of folate insufficiency in non-supplemented German women

Low folate status is a risk factor for birth defects. We studied concentrations of red blood cell (RBC)- and serum folate in 198 German women in relation to information on dietary folate intake, demographic and lifestyle factors. Median serum- and RBC-folate levels were; (14.7 and 589 nmol/L, respectively. Serum < 7.0 nmol/L or RBC-folate < 405 nmol/L were observed in 3.5% and 18.7% of the women, respectively. Three per cent of the women had both lowered serum and RBC-folate. Whereas RBC-folate > 952 nmol/L (optimal levels around conception) were observed in 9.6%. Serum- and RBC-folate were positively associated; they showed the expected correlations with homocysteine, but only weak correlations with folate intake. Younger age, lower fibre and higher carbohydrate intakes were associated with lower blood folate. Thus, folate intake of approximately 278 µg/d was not sufficient to achieve optimal folate status in young women. In conclusion, in the absence of fortification with folic acid, the majority of the women did not achieve folate status that is optimal for prevention of birth defects.

Correlation between global methylation level of peripheral blood leukocytes and serum C reactive protein level modified by MTHFR polymorphism: a cross-sectional study

BACKGROUND

Chronic inflammatory conditions are associated with higher tumor incidence through epigenetic and genetic alterations. Here, we focused on an association between an inflammation marker, C-reactive-protein (CRP), and global DNA methylation levels of peripheral blood leukocytes.

METHODS

The subjects were 384 healthy Japanese women enrolled as the control group of a case-control study for breast cancer conducted from 2001 to 2005. Global DNA methylation was quantified by Luminometric Methylation Assay (LUMA).

RESULTS

With adjustment for lifestyle-related factors, including folate intake, the global DNA methylation level of peripheral blood leukocytes was significantly but weakly increased by 0.43% per quartile category for CRP (P for trend = 0.010). Estimated methylation levels stratified by CRP quartile were 70.0%, 70.8%, 71.4%, and 71.3%, respectively. In addition, interaction between polymorphism of MTHFR (rs1801133, known as C677T) and CRP was significant (P for interaction = 0.046); the global methylation level was significantly increased by 0.61% per quartile category for CRP in the CT/TT group (those with the minor allele T, P for trend = 0.001), whereas no association was observed in the CC group (wild type).

CONCLUSIONS

Our study suggests that CRP concentration is weakly associated with global DNA methylation level. However, this association was observed more clearly in individuals with the minor allele of the MTHFR missense SNP rs1801133. By elucidating the complex mechanism of the regulation of DNA methylation by both acquired and genetic factors, our results may be important for cancer prevention.

High doses of folic acid in the periconceptional period and risk of low weight for gestational age at birth in a population based cohort study

PURPOSE

We investigated the association between maternal use of folic acid (FA) during pregnancy and child anthropometric measures at birth.

METHODS

We included 2302 mother-child pairs from a population-based birth cohort in Spain (INMA Project). FA dosages at first and third trimester of pregnancy were assessed using a specific battery questionnaire and were categorized in non-user, < 1000, 1000-4999, and ≥ 5000 µg/day. Anthropometric measures at birth (weight in grams, length and head circumference in centimetres) were obtained from medical records. Small for gestational age according to weight (SGA-w), length (SGA-l) and head circumference (SGA-hc) were defined using the 10th percentile based on Spanish standardized growth reference charts. Multiple linear and logistic regression analyses were used to explore the association between FA dosages in different stages of pregnancy and child anthropometric measures at birth.

RESULTS

In the multiple linear regression analysis, we found a tendency for a negative association between the use of high dosages of FA (≥ 5000 µg/day) in the periconceptional period of pregnancy and weight at birth compared to mothers who were non-users of FA (β = - 73.83; 95% CI - 151.71, 4.06). In the multiple logistic regression, a greater risk of SGA-w was also evident among children whose mothers took FA dosages of 1000-4999 (OR = 2.21; 95% CI 1.17, 4.19) and of ≥ 5000 µg/day (OR = 2.32; 95% CI 1.06, 5.08) compared to mothers non-users of FA in the periconceptional period of pregnancy.

CONCLUSION

Our findings suggest that a high dosage of FA (≥ 1000 µg/day) may be associated with an increased risk of SGA-w at birth.

Dietary intake and biomarker status of folate in Swedish adults

PURPOSE

National data on folate status are missing in Sweden, and regional data indicate folate insufficiency in up to more than 25% of the study populations. The objectives were to determine folate intake and status in the adult Swedish population as well as identifying dietary patterns associated with beneficial folate status.

METHODS

Folate intake was estimated using a web-based 4-d food record in adults aged 18-80 years (n = 1797). Folate status was measured as erythrocyte (n = 282) and plasma folate concentrations (n = 294). Factor analysis was used to derive a dietary pattern associated with a higher folate status.

RESULTS

Median folate intake was 246 µg/day (Q ₁ = 196, Q ₃ = 304, n = 1797) and for women of reproductive age 227 µg/day (Q ₁ = 181, Q ₃ = 282, n = 450). As dietary folate equivalents (DFE), median intake was 257 µg/day (Q ₁ = 201, Q ₃ = 323) and for women of reproductive age 239 µg/day (Q ₁ = 185, Q ₃ = 300). Low blood folate concentrations were found in 2% (erythrocyte concentrations <317 nmol/L) and 4% (plasma concentrations <6.8 nmol/L) of the participants, respectively. None of the women of reproductive age had erythrocyte folate concentrations associated with the lowest risk of neural tube defects. Dietary patterns associated with higher folate status were rich in vegetables, pulses and roots as well as cheese and alcoholic beverages, and low in meat.

CONCLUSIONS

Prevalence of low erythrocyte folate concentrations was low in this population, and estimated dietary intakes are well above average requirement. However, to obtain a folate status optimal for prevention of neural tube defects major dietary changes are required and folic acid supplements recommended prior to conception.

Intake and blood concentrations of folate and their association with health-related behaviors in Korean college students

The purpose of this study is to assess folate intake, and serum and red blood cell (RBC) folate concentrations, and investigate the association between folate status and health-related behaviors among Korean college students. A total of 169 students, aged between 18 and 27 years, participated in this study. Dietary intake data were collected by trained interviewers using a 24-hour recall method for three non-consecutive days in 2009. Information on health-related behaviors was obtained by a self-administered questionnaire. Serum and RBC folate concentrations were measured by microbiological assay. The average intakes of folate were 456 µgDFE and 347 µgDFE in male and female students, respectively. While the average serum folate concentration was significantly lower in male students (8.9 ng/mL) compared to female students (12.5 ng/mL), RBC concentrations were not significantly different between male (398.6 ng/mL) and female students (405.3 ng/mL). In male students, low serum folate concentrations were associated with total folate intake less than the Estimated Average Requirement, non-use of folic acid supplements, smoking, alcohol drinking at least once a week and low physical activity. In female students, low serum folate concentrations were associated with smoking and alcohol drinking at least two drinks at a time and BMI ≥ 25. Alcohol drinking and low physical activity were also associated with low RBC folate concentrations in both male and female students. In order to improve folate nutritional status of college students, the practice of desirable health-related behaviors, such as non-smoking, moderate alcohol drinking, regular physical activity, and maintenance of healthy BMI should be encouraged along with consumption of folate-rich foods and supplements.

Methylenetetrahydrofolate reductase genetic polymorphisms and esophageal squamous cell carcinoma susceptibility: A meta-analysis of case-control studies

OBJECTIVES

Genetic factors and environmental factors play a role in pathogenesis of esophageal squamous cell carcinoma (ESCC). Previous studies regarding the association of folate intake and Methylenetetrahydrofolate reductase C677T polymorphism with ESCC was conflicting. We conducted a meta-analysis to investigate the association of MTHFR C677T and folate intake with esophageal cancer risk.

METHODOLOGY

MEDLINE, EMBASE and the Chinese Biomedical Database were searched in our study. The quality of studies were evaluated by predefined scale, and The association of polymorphisms of MTHFR C677T and folate intake and ESCC risk was estimated by Odds ratio (ORs) with 95% confidence intervals (CIs).

RESULTS

Nineteen studies (4239 cases and 5575 controls) were included for meta-analysis. A significant association was seen between individuals with MTHFR 677 CT [OR(95%)=1.47(1.32-1.63)] and TT [OR(95%)=1.69(1.49-1.91)] genotypes and ESCC risk (p<0.05). Low intake of folate had significantly higher risk of esophageal cancer among individuals with CT/TT genotype [OR(95%)=1.65(1.1-2.49)], while high intake of folate did not find significant high risk of esophageal cancer among individuals with CT/TT genotype [OR(95%)=1.64 (0.82-3.26)].

CONCLUSIONS

Our meta-analysis indicated the folate intake and MTHFR 677CT/TT are associated with the risk of ESCC, and folate showed a significant interaction with polymorphism of MTHFR C677T.