Dietary intake of folate, other B vitamins, and omega-3 polyunsaturated fatty acids in relation to depressive symptoms in Japanese adults

OBJECTIVE: Although a favorable effect of dietary folate and omega-3 polyunsaturated fatty acids (PUFAs) on depression is suggested from epidemiologic studies in Western countries, evidence from non-Western populations is lacking. We examined cross-sectional associations between the intake of folate, other B vitamins, and omega-3 PUFAs and depressive symptoms in Japanese adults. METHODS: Subjects were 309 Japanese men and 208 Japanese women 21-67 y of age. Dietary intake was assessed with a validated, brief, self-administered diet history questionnaire. Depressive symptoms were defined as present when subjects had a Center for Epidemiologic Studies Depression scale score > or =16. Adjustment was made for age, body mass index, work place, marital status, occupational physical activity, leisure-time physical activity, current smoking, current alcohol drinking, and job stress score. RESULTS: The prevalences of depressive symptoms were 36% for men and 37% for women. Folate intake showed a statistically significant, inverse, and linear association with depressive symptoms in men but not in women. The multivariate odds ratios (95% confidence intervals) for depressive symptoms for men in the first, second, third, and fourth quartiles of folate intake were 1.00 (reference), 0.78 (0.38-1.63), 0.57 (0.27-1.18), and 0.50 (0.23-1.06), respectively (P for trend = 0.045). No statistically significant linear association was observed for the intake of riboflavin, pyridoxine, cobalamin, total omega-3 PUFAs, alpha-linolenic acid, eicosapentaenoic acid, or docosahexaenoic acid in either sex. CONCLUSION: Higher dietary intake of folate was associated with a lower prevalence of depressive symptoms in Japanese men but not women.     

B vitamin status and concentrations of homocysteine and methylmalonic acid in elderly German women

BACKGROUND: Prior investigations found that elderly persons are at higher risk than are younger persons for B vitamin deficiency, which leads to elevated plasma total homocysteine (tHcy) concentrations that are associated with an increased risk for certain diseases such as coronary artery disease. To date, published data have shown decreased vitamin status and elevated tHcy among the elderly. OBJECTIVE: We evaluated the dietary intake and the blood status of various B vitamins and tHcy and methylmalonic acid (MMA) concentrations in 178 younger (60-70-y-old) female seniors. DESIGN: Dietary intake was assessed with a 3-d diet record. Thiamine, riboflavin, and vitamin B-6 activity coefficients of erythrocyte transketolase (EC 2.2.1.1), erythrocyte glutathione reductase (EC 1.6.4.2), and erythrocyte alpha-aspartic aminotransferase (EC 2.6.1.1) were used as functional indexes for the status of the 3 vitamins, respectively. Concentrations of serum and red blood cell folate, serum cobalamin and MMA, and plasma tHcy were measured. RESULTS: Indexes of thiamine, pyridoxine, and cobalamin indicated insufficient status in one-third of the women, whereas tHcy and MMA concentrations were elevated in 17.4% and 9.6% of the women, respectively. An association between vitamin intake and vitamin concentration in the blood was found only for folate. The mean tHcy concentration in subjects in the lowest quartile of serum folate concentration was 23% higher than that in subjects in the highest quartile. There was no association between riboflavin and tHcy concentrations. MMA was positively correlated with age and inversely correlated with serum cobalamin concentration. CONCLUSIONS: Even in younger, well-educated, female seniors, the prevalence of low B vitamin status and elevated plasma tHcy concentration is high. Thiamine, pyridoxine, folate, and cobalamin supplementation should be considered.     

Association between folate, vitamin B6 and vitamin B12 intake and depression in the SUN cohort study

Background:  An association between low blood levels of folate, vitamins B₆ and B₁₂ and a higher prevalence of depressive symptoms has been reported in several epidemiological studies. The present study aimed to assess the association between folate, vitamins B₆ and B₁₂ intake and depresion prevalence in the SUN cohort study.
Methods:  The study comprised a cross-sectional analysis of 9670 participants. A validated semi-quantitative food frequency questionnaire was used to ascertain vitamin intake. The association between the baseline intake of folate, vitamins B₆ and B₁₂ categorised in quintiles and the prevalence of depression was assessed. The analyses were repeated after stratifying by smoking habits, alcohol intake, physical activity and personality traits.
Results:  Among women, odds ratios (OR) [95% confidence interval (CI)] for the third to fifth quintile for vitamin B₁₂ intake were 0.58 (0.41–0.84), 0.56 (0.38–0.82) and 0.68 (0.45–1.04), respectively. Among those men with a low level of anxiety and current smokers, a significant positive association between low folate intake and the prevalence of depression was found. The OR (95% CI) for the first quintile of intake was 2.85 (1.49–5.45) and 2.18 (1.08–4.38), respectively, compared to the upper quintiles of intake (Q2–Q5) considered as a group.
Conclusion:  Low folate intake was associated with depression among currently smoking men and men with low anxiety levels. Low intake of vitamin B₁₂ was associated with depression among women. No significant associations were found for vitamin B₆ intake.     

B-vitamins in Relation to Depression in Older Adults Over 60 Years of Age: The Trinity Ulster Department of Agriculture (TUDA) Cohort Study

ObjectivesMental health disorders are major contributors to disease burden in older people. Deficient status of folate and the metabolically related B vitamins may be implicated in these conditions. This study aimed to investigate folate, vitamin B₁₂, vitamin B₆, and riboflavin in relation to depression and anxiety in aging and also considered the role of fortified foods as a means of optimizing B-vitamin status and potentially reducing the risk of these mental health disorders.DesignThe Trinity Ulster Department of Agriculture (TUDA) aging study was a cross-sectional cohort study.Setting and ParticipantsCommunity-dwelling adults (n = 5186; ≥60 years) recruited from 2 jurisdictions within the island of Ireland from 2008 to 2012.MeasuresDepression and anxiety were assessed using the Centre for Epidemiological Studies Depression (CES-D) and the Hospital Anxiety and Depression (HAD) scales, respectively. The following B-vitamin biomarkers were measured: red blood cell folate, serum total vitamin B₁₂, plasma pyridoxal-5-phosphate (PLP; vitamin B₆), and erythrocyte glutathione reductase activation coefficient (EGRac; riboflavin).ResultsBiomarker values in the lowest 20% of status for folate (odds ratio [OR] 1.79; 95% CI 1.23-2.61), vitamin B₆ (OR 1.45, 95% CI 1.01-2.06), or riboflavin (OR 1.56, 95% CI 1.10-2.00), but not vitamin B₁₂, were each associated with an increased risk of depression (CES-D score ≥16). Correspondingly, B vitamin–fortified foods if consumed daily were associated with a reduced risk of depression (OR 0.54, 95% CI 0.41-0.70). A deficient status of vitamin B₆ (OR 1.73, 95% CI 1.07-2.81), but not other vitamins, was associated with increased anxiety.Conclusions/ImplicationsBetter B-vitamin status may have a role in impacting positively on mental health in older adults. Regular intake of fortified foods can provide a means of optimizing B-vitamin status and thus could contribute to reducing depression. If confirmed by a randomized trial, these results may have implications for nutrition and mental health policy, and thus quality of life, in older people.     

Poor folate status predicts persistent diarrhea in 6- to 30-month-old north Indian children

Poor micronutrient status is associated with diarrheal illness, but it is not known whether low folate and/or cobalamin status are independent risk factors for diarrhea. We measured the association between plasma folate and cobalamin and subsequent diarrheal morbidity in a prospective cohort study of 2296 children aged 6-30 mo in New Delhi, India. Plasma concentrations of folate, cobalamin, total homocysteine (tHcy), and methylmalonic acid were determined at baseline. Whether a child had diarrhea was recorded during weekly visits in a 4-mo zinc supplementation trial. Diarrhea episodes lasting <7, ≥7, and ≥14 d were classified as acute, prolonged, and persistent, respectively. There was a total of 4596 child periods with acute, 633 with prolonged, and 117 with persistent diarrhea during follow-up. Children with plasma folate concentrations in the lowest quartile had higher odds of persistent diarrhea than children in the other quartiles [adjusted OR = 1.77 (95% CI = 1.14, 2.75); P = 0.01]. This effect differed between boys [adjusted OR = 2.51 (95% CI = 1.47, 4.28)] and girls [adjusted OR = 1.03 (95% CI = 0.53, 2.01); P-interaction = 0.030]. We found a small but significant association between high plasma tHcy concentration and acute diarrhea [adjusted OR = 1.14 (95% CI = 1.04, 1.24); P = 0.006]. Plasma cobalamin concentration was not a predictor of diarrheal morbidity. In conclusion, poor folate status was an independent predictor of persistent diarrhea in this population.     

Polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene, intakes of folate and related B vitamins and colorectal cancer: a case-control study in a population with relatively low folate intake

Folate is key in one-carbon metabolism, disruption of which can interfere with DNA synthesis, repair, and methylation. Efficient one-carbon metabolism requires other B vitamins and the optimal activity of enzymes including 5,10-methylenetetrahydrofolate reductase (MTHFR). We report a population-based case-control study of folate intake, related dietary factors and MTHFR polymorphisms (C677T, A1298C) and colorectal cancer in a population with relatively high colorectal cancer incidence and relatively low folate intake. A total of 264 cases with histologically confirmed incident colorectal cancer and 408 controls participated. There was no clear trend in risk with reported intakes of total, or dietary, folate, riboflavin, vitamin B12 or vitamin B6, nor were there interactions between folate intake and the other B vitamins or alcohol. For C677T, risk decreased with increasing variant alleles (multivariate OR for CT v. CC = 0.77 (95 % CI 0.52, 1.16); OR for TT v. CC = 0.62 (95 % CI 0.31, 1.24)), which, although not statistically significant, was consistent with previous studies. For A1298C, compared with AA subjects, CC subjects had modest, non-significant, reduced risk (multivariate OR = 0.81 (95 % CI 0.45, 1.49)). There were significant interactions between total folate and C677T (P = 0.029) and A1298C (P = 0.025), and total vitamin B6 and both polymorphisms (C677T, P = 0.016; A1298C, P = 0.033), although the patterns observed differed from previous studies. Seen against the setting of low folate intake, the results suggest that the role of folate metabolism in colorectal cancer aetiology may be more complex than previously thought. Investigation of particular folate vitamers (for example, tetrahydrofolate, 5,10-methylenetetrahydrofolate) may help clarify carcinogenesis pathways.     

Alterations of Homocysteine Serum Levels during Alcohol Withdrawal Are Influenced by Folate and Riboflavin: Results from the German Investigation on Neurobiology in Alcoholism (GINA)

Aims: Various studies have shown that plasma homocysteine (HCY) serum levels are elevated in actively drinking alcohol-dependent patients a during alcohol withdrawal, while rapidly declining during abstinence. Hyperhomocysteinemia has been associated not only with blood alcohol concentration (BAC), but also with deficiency of different B-vitamins, particularly folate, pyridoxine and cobalamin. Methods: Our study included 168 inpatients (110 men, 58 women) after admission for detoxification treatment. BAC, folate, cobalamin, pyridoxine, thiamine and riboflavin were obtained on admission (Day 1). HCY was assessed on Days 1, 7 and 11. Results: HCY levels significantly declined during withdrawal. General linear models and linear regression analysis showed an influence of BAC, folate and riboflavin on the HCY levels on admission as well as on HCY changes occurring during alcohol withdrawal. No significant influence was found for thiamine, cobalamin and pyridoxine. Conclusions: These findings show that not only BAC and plasma folate levels, but also plasma levels of riboflavin influence HCY plasma levels in alcohol-dependent patients.     

Is low folate a risk factor for depression? A meta‐analysis and exploration of heterogeneity

Low folate has been causatively linked to depression, but research is contradictory. An association may arise due to chance, bias, confounding or reverse causality. A systematic review of observational studies which examined the association between depression and folate was conducted. 11 relevant studies (15 315 participants; three case-control studies, seven population surveys and one cohort study) examining the risk of depression in the presence of low folate were found. Pooling showed a significant relationship between folate status and depression (odds ratio (OR)(pooled unadjusted) = 1.55; 95% CI 1.26 to 1.91). This relationship remained after adjustment for potential confounding (OR)(pooled adjusted) = 1.42; 95% CI 1.10 to 1.83). Folate levels were also lower in depression. There is accumulating evidence that low folate status is associated with depression. Much of this evidence comes from case-control and cross-sectional studies. Cohort studies and definitive randomised-controlled trials to test the therapeutic benefit of folate are required to confirm or refute a causal relationship.     

The association between isoflavone and lower urinary tract symptoms in elderly men

The objective of the present study is to explore the association between lower urinary tract symptoms (LUTS) and dietary isoflavone in elderly men. In a large prospective cohort of 2000 Chinese men, the association between dietary isoflavone and LUTS were studied using standardized structured questionnaires. Dietary intake was assessed by a modified version of the Block FFQ. LUTS were assessed by the Chinese version of the International Prostatic Symptoms Score. Demographic, lifestyle and other medical information were also collected and were adjusted for in the analysis. After excluding 299 men with history of bladder surgery, bladder or prostate cancer or who were current users of medication for urinary problems, the association between LUTS and dietary isoflavone was explored. A total of 96.2 % of subjects reported some consumption of genistein, glycitein or daidzein. In ordinal multinominal logistic regression, subjects with dietary total isoflavone of more than 5.1 mg were significantly less likely to suffer from more severe LUTS (dietary intake from 5.1 to 9.5 mg: OR 0.59; 95 % CI 0.44, 0.80; from 9.6 to 14.3 mg: OR 0.81; 95 % CI 0.61, 1.09; from 14.4 to 21.7 mg: OR 0.68; 95 % CI 0.51, 0.92; 21.8 mg and above: OR 0.73; 95 % CI 0.54, 0.98) after adjustment for covariates. In this cross-sectional study, we showed a strong inverse association between dietary intake of isoflavone and the risk of LUTS.     

Case-control analysis of dietary folate and risk of bladder cancer

Dietary folate, a water-soluble B vitamin found in a variety of fruits and vegetables, is of particular interest as a chemopreventive agent due to its role in DNA methylation and DNA synthesis and repair. We hypothesized that individuals with low folate intake would be at an increased risk for bladder cancer. Using an ongoing case-control study we assessed dietary folate in 409 incident bladder cancer patients and 451 healthy control subjects. A food-frequency questionnaire was used to estimate naturally occurring food folate (microg/kcal/day), dietary folate equivalents (DFE) from food sources (microg DFE/kcal/day), and DFE from all sources (microg DFE/kcal/day). Unconditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Bladder cancer patients reported a statistically significant lower intake of folate than control subjects for food folate and DFE from food sources (P < 0.001) but not for DFE from all sources (P = 0.061). In the highest quartile of food folate intake there was a 54% reduced risk for bladder cancer (OR = 0.46; 95% CI = 0.29-0.73) after adjusting for age, gender, ethnicity, smoking, and total energy intake. Similarly, the highest quartile of intake was associated with a 59% reduced risk for DFE from food sources (OR = 0.41; 95% CI = 0.26-0.65) and a 35% reduced risk for DFE from all sources (OR = 0.65; 95% CI = 0.42-1.00). In the joint-effects analyses using never smokers with high folate intake as the reference group (OR = 1.0), heavy smokers with low food folate intake had a 2.31-fold (95% CI = 1.11-4.82) increased risk, whereas heavy smokers with high folate intake had a reduced OR of 1.31 (95% CI = 0.53-3.26). Although the ORs were not statistically significant, light smokers and high folate intake exhibited a protective effect (OR = 0.62; 95% CI = 0.20-1.94), whereas an increased risk was observed for light smoking and low folate intake (OR = 1.41; 95% CI = 0.57-3.45). These patterns were consistent for the joint effects of smoking and DFE from food sources and DFE from all sources. In summary, high intake of dietary folate was associated with an overall decrease in bladder cancer risk. These data may have important implications for cancer prevention; however, large, hypothesis-driven, population-based clinical trials will be required to confirm these findings.     

Dietary folate, vitamin B6, vitamin B12 and methionine intake and the risk of breast cancer by oestrogen and progesterone receptor status

Few studies have evaluated the relationship between the consumption of dietary folate and one-carbon metabolism-related nutrients and breast cancer risk defined by oestrogen receptor (ER) and progesterone receptor (PR) status. The objective of the present study was to examine the associations between dietary folate, vitamin B6, vitamin B12, and methionine intake and the risk of breast cancer by ER and PR status among Chinese women in Guangdong. A hospital-based case-control study was conducted from June 2007 to August 2008, with 438 cases and 438 age (5-year interval)- and residence (rural/urban)-matched controls. Dietary intake information was assessed using a validated FFQ administered through a face-to-face interview. Unconditional logistic regression models were used to calculate multivariate-adjusted OR and 95 % CI. A significant inverse association was found between dietary folate and vitamin B6 intake and breast cancer risk. The adjusted OR of the highest v. the lowest quartile were 0·32 (95 % CI 0·21, 0·49; P(trend) < 0·001) for dietary folate and 0·46 (95 % CI 0·30, 0·69; P(trend) < 0·001) for vitamin B6. No associations were observed for vitamin B12 and methionine intake. A significant inverse association between dietary folate intake and breast cancer risk was observed in all subtypes of ER and PR status. These findings suggest that dietary folate and vitamin B6 intakes were inversely associated with breast cancer risk. The inverse association did not differ by ER and/or PR status.     

Association between dietary omega-3 fatty acid intake and depression in postmenopausal women

BACKGROUND/OBJECTIVESThis study aimed to analyze the association between dietary omega-3 fatty acid intake and depression in postmenopausal women using data from the Korea National Health and Nutrition Examination Survey (KNHANES) VI.SUBJECTS/METHODSThe KNHANES is a cross-sectional nationwide health and nutrition survey. Dietary data, including omega-3 fatty acids, were assessed using the 24-h recall method. Depression was evaluated using a survey questionnaire. The association between dietary omega-3 fatty acids and depression was evaluated using multivariate logistic regression analysis. Depression, according to the dietary omega-3 fatty acid intake, was expressed as the odds ratio (OR) with a 95% confidence interval (CI). A total of 4,150 postmenopausal women were included in the analysis.RESULTSIn the fully-adjusted model, the group with the highest dietary omega-3 fatty acid intake significantly showed lower prevalence of depression than the group with the lowest intake (OR, 0.52; 95% CI, 0.33–0.83); a significant linear trend was detected (P for trend = 0.04). According to the dose-response analysis using cubic restricted spline regression, this association was linear and monotonic (P for non-linearity = 0.32).CONCLUSIONSIn this study, the dietary omega-3 fatty acid intake in postmenopausal women was inversely proportional to depression in a dose-response manner. Large cohort studies are needed to verify the causality between omega-3 fatty acids and depression in Korean postmenopausal women.     

Association of homocysteinemia with high concentrations of serum insulin and uric acid in Brazilian subjects with metabolic syndrome genotyped for C677T polymorphism in the methylenetetrahydrofolate reductase gene

Information on plasma homocysteine concentrations and their associated factors in Brazilian subjects with metabolic syndrome (MS) is nonexistent. Therefore, a cross-sectional study was conducted to investigate the association of homocysteinemia with MS components; folate and cobalamin biochemical and dietary indices of nutritional status; and genetic, anthropometric, and lifestyle factors in Brazilian subjects with MS. Waist circumference; body fat; body mass index; insulin resistance; lipid profiles; glycemia; uricemia; insulinemia; erythrocyte folate and plasma homocysteine; folate and cobalamin concentrations; C677T polymorphism in the methylenetetrahydrofolate reductase (MTHFR) gene; coffee and alcohol intake; and smoking were determined in 63 subjects (24 males and 39 females) with MS. No difference in homocysteine plasma was observed between sexes. Hyperhomocysteinemia (Hhcy) frequency was 49.2% (n = 31) in the group studied. The distribution of MTHFR genotypes was as follows: CC, 64% (n = 42); CT, 32% (n = 19); and TT, 4% (n = 2). No association was found between Hhcy and C677T polymorphism in the MTHFR gene. Plasma homocysteine concentrations showed no association with age; blood pressure; dietary intakes of folate, cobalamin, and pyridoxine; body mass index; waist circumference; body fat; glycemia; lipid profile; insulin resistance; and concentrations of folate erythrocyte and plasma folate and cobalamin. Also, there was no correlation between Hhcy, sex, and lifestyle factors. In this study, the variables uricemia (C = 0.67, χ² = 2.23, P = .27) and insulinemia (C = 0.86, χ² = 2.98, P = .07) were positively associated with homocysteinemia. In conclusion, our results suggest that high concentrations of serum insulin and uric acid are associated with an increased risk of developing Hhcy in subjects with MS.     

Plasma folate as marker of folate status in epidemiological studies: the European Investigation into Cancer and Nutrition (EPIC)-Potsdam study

Folate deficiency is often discussed as a potential risk factor for CVD and some cancers. Reliable assessment of folate status in large-scale epidemiological studies is therefore of major importance. The present study assessed the value of plasma folate (PF) compared with erythrocyte folate (EF) as a marker of folate status in 363 participants in the European Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort. EF and PF, total homocysteine (tHcy), pyridoxine, cobalamin, creatinine, total protein and packed cell volume were determined; glutamate carboxypeptidase (GCP) C1561T, reduced folate carrier (RFC) G80A and methylenetetrahydrofolate (MTHFR) C677T polymorphisms were analysed. Anthropometric measurements were taken and dietary intake was assessed with the EPIC-Potsdam food-frequency questionnaire. Comparison of EF and PF with factors that may modulate their concentrations was performed. Cross-classification of blood folates in quintile categories resulted in correct classification into the same or adjacent category of 75.5 % of all subjects. Age, BMI, pyridoxine and cobalamin, fruit and vegetable intake, and vitamin supplementation 24 h before blood draw were positively associated with EF and with PF. For tHcy an inverse association was found. Participants with the MTHFR 677TT genotype showed significantly elevated EF concentrations compared with those with 677CT genotype; EF and PF were more strongly correlated (r 0.78, P<0.0001) for participants with MTHFR 677TT genotype than for those with the 677CC or 677CT genotype. In summary, our present results indicate that plasma folate seems to be a suitable marker for assessment of folate status for use in large-scale epidemiological studies.     

Folate intake, alcohol use, and postmenopausal breast cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

BACKGROUND: Several epidemiologic studies suggest that higher folate intakes are associated with lower breast cancer risk, particularly in women with moderate alcohol consumption. OBJECTIVE: We investigated the association between dietary folate, alcohol consumption, and postmenopausal breast cancer in women from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial cohort. DESIGN: Dietary data were collected at study enrollment between 1993 and 2001. Folate content was assigned on the basis of prefortification (ie, pre-1998) databases. Of the 25 400 women participants with a baseline age of 55-74 y and with complete dietary and multivitamin information, 691 developed breast cancer between September 1993 and May 2003. We used Cox proportional hazard models with age as the underlying time metric to generate hazard ratios (HRs) and 95% CIs. RESULTS: The adjusted HRs were 1.19 (95% CI: 1.01, 1.41; P for trend = 0.04) for women reporting supplemental folic acid intake >/=400 mug/d compared with subjects reporting no supplemental intake. Comparison of the highest with the lowest quintile gave adjusted HRs of 1.04 (95% CI: 0.83, 1.31; P for trend = 0.56) and 1.32 (95% CI: 1.04, 1.68; P for trend = 0.03) for food and total folate intake, respectively. Alcohol consumption was positively associated with breast cancer risk (highest compared with lowest quintile: HR = 1.37; 95% CI: 1.08, 1.76; P for trend = 0.02); the risk was greatest in women with lower total folate intake. CONCLUSIONS: Our results do not support the hypothesis that high folate intake reduces breast cancer risk; instead, they suggest that a high intake, generally attributable to supplemental folic acid, may increase the risk in postmenopausal women. However, our results confirm previous studies showing positive associations between moderate alcohol consumption and breast cancer.     

Nutritional factors and susceptibility to arsenic-caused skin lesions in West Bengal, India

There has been widespread speculation about whether nutritional deficiencies increase the susceptibility to arsenic health effects. This is the first study to investigate whether dietary micronutrient and macronutrient intake modulates the well-established human risk of arsenic-induced skin lesions, including alterations in skin pigmentation and keratoses. The study was conducted in West Bengal, India, which along with Bangladesh constitutes the largest population in the world exposed to arsenic from drinking water. In this case-control study design, cases were patients with arsenic-induced skin lesions and had < 500 microg/L arsenic in their drinking water. For each case, an age- and sex-matched control was selected from participants of a 1995-1996 cross-sectional survey, whose drinking water at that time also contained < 500 microg/L arsenic. Nutritional assessment was based on a 24-hr recall for major dietary constituents and a 1-week recall for less common constituents. Modest increases in risk were related to being in the lowest quintiles of intake of animal protein [odds ratio (OR) = 1.94; 95% confidence interval (CI), 1.05-3.59], calcium (OR = 1.89; 95% CI, 1.04-3.43), fiber (OR = 2.20; 95% CI, 1.15-4.21), and folate (OR = 1.67; 95% CI, 0.87-3.2). Conditional logistic regression suggested that the strongest associations were with low calcium, low animal protein, low folate, and low fiber intake. Nutrient intake was not related to arsenic exposure. We conclude that low intake of calcium, animal protein, folate, and fiber may increase susceptibility to arsenic-caused skin lesions. However, in light of the small magnitude of increased risks related to these dietary deficiencies, prevention should focus on reducing exposure to arsenic.     

High folate intake is associated with lower breast cancer incidence in postmenopausal women in the Malmö Diet and Cancer cohort

BACKGROUND: Epidemiologic studies of associations between folate intake and breast cancer are inconclusive, but folate and other plant food nutrients appear protective in women at elevated risk. OBJECTIVE: The objective was to examine the association between folate intake and the incidence of postmenopausal breast cancer. DESIGN: This prospective study included all women aged >or=50 y (n = 11699) from the Malm? Diet and Cancer cohort. The mean follow-up time was 9.5 y. We used a modified diet-history method to collect nutrient intake data. At the end of follow-up, 392 incident invasive breast cancer cases were verified. We used proportional hazard regression to calculate hazard ratios (HRs). RESULTS: Compared with the lowest quintile, the incidence of invasive breast cancer was reduced in the highest quintile of dietary folate intake (HR: 0.56; 95% CI: 0.35, 0.90; P for trend = 0.02); total folate intake, including supplements (HR: 0.56; 95% CI: 0.34, 0.91; P for trend = 0.006); and dietary folate equivalents (HR: 0.59; 95% CI: 0.36, 0.97; P for trend = 0.01). CONCLUSION: A high folate intake was associated with a lower incidence of postmenopausal breast cancer in this cohort.     

Folate intake and pancreatic cancer risk: an overall and dose–response meta-analysis

Objective

Inconsistent findings of association between supplemental folate consumption and pancreatic cancer risk have been observed in the literature. This study aims to summarize the relationship between folate intake and risk of pancreatic cancer.

Study design

Pertinent studies published before November 2011 were identified by searching PubMed and Embase and by reviewing the reference lists of retrieved articles. The summary relative risks were estimated by the random effects model. A linear regression analysis of the natural logarithm of the relative risk (RR) was carried out to assess a possible dose–response relationship between folate intake and pancreatic cancer risk.

Results

Ten studies on dietary and supplemental folate intake and pancreatic cancer (4 case–control and 6 cohort studies) were included in the meta-analysis. The pooled RRs of pancreatic cancer for the highest vs lowest categories of dietary folate intake and supplemental folate intake were 0.66 (95% CI: 0.49–0.88) and 1.08 (95% CI, 0.82–1.41), respectively. The dose–response meta-analysis indicated that a 100 μg/day increment in dietary folate intake conferred a RR of 0.93 (95% CI: 0.90–0.97). These findings support the hypothesis that dietary folate may play a protective role in carcinogenesis of pancreatic cancer.     

Dietary factors in the aetiology of postnatal depression

Summary   Prevalence of postnatal depression (PND) occurs in approximately 13–20% of women after birth and has detrimental consequences for both the mother and the offspring. The causes of PND remain unclear, with research suggesting a multifactorial aetiology. It is believed that some dietary constituents may, in part, be related to the onset of PND. The possible protective roles of folate, riboflavin, calcium, magnesium and zinc intake have been investigated, as well as the role of a high glycaemic index diet, with conflicting results. Most of the literature appears to have focused on the symptoms of PND in relation to patterns of fish consumption and intake of n -3(omega-3) fatty acids. A review of studies published through MEDLINE indicated that riboflavin, calcium and zinc may play a role in alleviating symptoms of PND. Although a greater number of published papers have studied associations between n -3 intake and PND incidence, findings are somewhat contradictory. Further research is now required to develop these preliminary research findings with an aim to reducing the health costs of PND through the application of nutritional interventions.