Smoking status in relation to serum folate and dietary vitamin intake

Folate Biomarkers, Folate Intake, and Risk of Death From All Causes, Cardiovascular Disease, and Cancer: A Systematic Review and Dose-Response Meta-Analysis of Prospective Cohort Studies

CONTEXT

Existing evidence on the relation between folate intake and biomarkers with mortality risk is controversial.

OBJECTIVE

Previous cohort studies were examined regarding folate intake and biomarkers in relation to risk of all-cause, cardiovascular disease- (CVD), and cancer-related mortality through a systematic review and meta-analysis.

DATA SOURCES

A systematic search was performed of the PubMed, Scopus, and ISI Web of Science databases up to July 2023.

DATA EXTRACTION

Prospective cohort studies examining the association of folate biomarkers (in serum, plasma, red blood cells) and intake with risk of all-cause, CVD-, and cancer-related mortality were considered. A random-effects model was applied to combine study-specific risk estimates. Dose-response relations were assessed by 1-stage weighted mixed-effects meta-analysis.

DATA ANALYSIS

A total of 25 cohorts with 423 304 participants, 36 558 all-cause, 12 662 CVD-, and 2426 cancer-related deaths were included. No significant association was observed between the highest levels of folate biomarkers and all-cause mortality risk (hazard ratio [HR], 0.91; 95% CI, 0.77-1.06; n = 17; I2 = 89.4%; P < .001), CVD-related mortality risk (HR, 0.97; 95% CI, 0.87-1.06; n = 11; I2 = 0.0%; P = .57), and cancer-related mortality risk (HR, 0.85; 95% CI, 0.69-1.05; n = 6; I2 = 57.8%; P = .04) compared with the lowest. Furthermore, each 10 nmol/L increase was marginally related to a 12% reduced all-cause mortality risk but not to CVD- and cancer-related mortality risk. A significant inverse association was found between highest intake of dietary folate and the lowest, and risk of all-cause (HR, 0.87; 95% CI, 0.78-0.96; n = 3; I2 = 63.6%; P = .06) and CVD (HR, 0.77; 95% CI, 0.57-0.93; n = 4; I2 = 80.2%; P = .002) mortality.

CONCLUSIONS

This meta-analysis revealed a significant inverse relation between dietary folate intake and risk of all-cause and CVD mortality. Such an association was not found in the case of folate biomarkers. Further prospective studies are warranted to confirm these findings.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42023401700.

Impact of Serum Vitamin D, B6, and B12 and Cognitive Functions on Quality of Life in Peri- and Postmenopausal Polish Women

BACKGROUND Menopause initiates or accelerates health problems in a woman’s life, and affects cognitive processes and quality of life. We aimed to assess the quality of life, cognitive functions, and serum vitamin D, B6, and B12 concentrations in perimenopausal and postmenopausal Polish women. Also, we correlated the assessment of the quality of life with these vitamin concentrations and cognitive functions. MATERIAL AND METHODS The study was conducted in 287 perimenopausal and postmenopausal women. Serum levels of vitamin D, B6, and B12, cognitive functions using CNS Vital Signs software, and quality of life using WHO Quality of Life Brief were tested. RESULTS Almost all of the perimenopausal and postmenopausal women had normal concentrations of serum vitamin B12 (96%), 80% of them had normal B6 concentration, while only 9% had optimal serum vitamin D concentration. Postmenopausal women had lower Neurocognitive Index, psychomotor speed, motor speed, reaction time, and lower assessment of overall quality of life, physical health, and social relationships compared to perimenopausal women. In comparison to postmenopausal women, perimenopausal women had a lower serum vitamin B6 concentration, and the lower the concentration of this vitamin in serum they had, the lower they assessed their environment. Perimenopausal women assessed their social relationships the better, the better the visual memory, and the lower the processing speed they had. Postmenopausal women assessed the environment the better, the higher their Neurocognition Index was, and the better the reaction time they had. CONCLUSIONS Assessment of quality of life was associated with some cognitive functions in both perimenopausal and postmenopausal women.

The dietary inflammatory index and new-onset hypertension in Chinese adults: a nationwide cohort study

Purpose: The development of hypertension is shown to be triggered by chronic low-grade inflammation. The dietary inflammatory index (DII) is a parameter for assessing the potential of a diet to cause inflammation. The prospective association between the DII and new-onset hypertension in Chinese adults remains unclear. Materials and methods: The nationwide cohort study included 10694 participants from 7 rounds of the China Health and Nutrition Survey. Dietary nutrient intake data were collected by 3-day 24 h dietary recalls and used to calculate the DII. The time-dependent Cox regression model was used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for studying the risk of new-onset hypertension, and stratified analyses were used to examine factors that may modify the association. Restricted cubic spline (RCS) regression was used to examine the non-linear relationship between the DII and new-onset hypertension. The relationship between the DII and physical activity was analyzed with the time-dependent Cox regression model. Results: The highest quartile of the DII had a significantly higher risk of new-onset hypertension compared to the lowest quartile (adjusted HR, 1.13; 95% CI, 1.02, 1.24). RCS regression results showed that the risk of new-onset hypertension increased significantly after the DII above 1.09 (P for non-linearity <0.001). The interaction results showed that the DII may play a better role (P < 0.05) in the female, age < 45 years, baseline SBP < 130 mmHg, DBP < 80 mmHg, BMI < 24 kg m-2 and moderate/heavy physical activity level subgroup. Stratified analysis results showed that the baseline SBP, DBP, obesity, and physical activity level modified the association between the DII and hypertension (P for interaction < 0.05). Conclusion: Reducing the inflammatory potential of the diet is an effective strategy to prevent hypertension in Chinese adults.

Interaction between serum vitamin C levels and smoking on the periodontal condition in older adults

BACKGROUND AND OBJECTIVES

Several epidemiological studies have reported that smokers have a higher prevalence and severity of periodontal disease than do nonsmokers, and that smoking negatively affects nutritional status and is associated with a reduced intake of antioxidants, particularly vitamin C. The present investigation aimed to examine the relationship between serum vitamin C levels and smoking and its influence on the periodontal condition in older adults.

MATERIALS AND METHODS

A total of 353 respondents met the inclusion criteria and were enrolled in the present study. The periodontal status of the study participants was determined through examinations of one or more residual teeth, which included a measurement of the probing pocket depth (PPD) and clinical attachment level (CAL) at six regions of each tooth. Blood samples were collected during the dental examinations and then sent to a laboratory to evaluate serum vitamin C and cotinine levels. A serum cotinine concentration of 100 ng/ml was considered a relevant threshold for active smoking. After dividing the participants into two groups according to serum cotinine levels, Poisson regression analysis was carried out to compare vitamin C levels with the prevalence rate ratio (PRR) for periodontal condition markers for each group based on serum cotinine levels.

RESULTS

We evaluated differences in the PRR of serum vitamin C tertiles between participants with high (≥100 ng/ml) or low (<100 ng/ml) serum cotinine levels after adjusting for sex, the use of interdental brushes or dental floss, and the number of teeth. A negative tendency between the PRR of vitamin C tertiles for the PPD or CAL was seen for both groups. Especially, a bigger difference was observed in the group with high serum cotinine levels. The PRR of the first tertiles in the high serum cotinine group was 5.03, compared with 2.69 in the low serum cotinine group (relative risk: 1.9).

CONCLUSION

The results of this study suggest a potential association between vitamin C levels and the periodontal condition, which may be influenced by smoking status.

Epigenetic Determinants of Racial Disparity in Breast Cancer: Looking beyond Genetic Alterations

Simple Summary

A substantial disparity in breast cancer incidence and mortality exists between African American (AA) and European American (EA) women. However, the basis for these disparities is poorly understood. In this article, we describe that gene–environment interactions mediated through epigenetic modifications may play a significant role in racial disparities in BC incidence and outcomes. Our in silico analyses and an in-depth literature survey suggest that there exists a significant difference in epigenetic patterns between AA and EA women with breast cancer. Herein, we describe the environmental factors that contribute to these epigenetic changes, which may underlie the disparate racial burden in patients with breast cancer. We suggest that AA women with higher basal epigenetic changes, may have higher pre-disposition to cancer onset, and an aggressive disease course. Pre-existing racial differences in epigenetic profiles of breast tissues raises the possibility of examining these profiles for early diagnosis.

Abstract

Breast cancer (BC) is the most commonly diagnosed cancer in women. Despite advancements in BC screening, prevention, and treatment, BC incidence and mortality remain high among African American (AA) women. Compared with European American (EA) women, AA women tend to be diagnosed with more advanced and aggressive tumors and exhibit worse survival outcomes. Most studies investigating the determinants of racial disparities in BC have focused on genetic factors associated with African ancestry. However, various environmental and social stressors over an individual’s life course can also shape racial stratification in BC. These social and environmental exposures result in long-term changes in gene expression mediated by epigenetic mechanisms. Epigenetics is often portrayed as an intersection of socially patterned stress and genetic expression. The enduring nature of epigenetic changes makes them suitable for studying the effects of different environmental exposures over an individual’s life course on gene expression. The role of differential social and environmental exposures in racial disparities in BC suggests varied epigenetic profiles or signatures associated with specific BC subtypes in AA and EA women. These epigenetic profiles in EA and AA women could be used as biomarkers for early BC diagnosis and disease prognosis and may prove valuable for the development of targeted therapies for BC. This review article discusses the current state of knowledge regarding epigenetic differences between AA and EA women with BC. We also discuss the role of socio-environmental factors, including psychosocial stress, environmental toxicants, and dietary factors, in delineating the different epigenetic profiles in AA and EA patients with BC.

Folate and vitamin B12 status: temporal evaluation after mandatory fortification in Brazil

OBJECTIVES

To perform temporal evaluation of folate and vitamin B12 status and their associated factors in a Brazilian population exposed to mandatory fortification.

METHODS

Data from the cross-sectional population-based studies 2008 and 2015 Health Surveys of São Paulo, including individuals ≥ 20 years, both sexes, N = 549 in 2008 and N = 610 in 2015. Folate and vitamin B12 biomarkers status, B-complex supplements and medications use, and dietary intake were assessed.

RESULTS

Serum folate concentrations increased in the entire population, adults and older adults in 2015 compared to 2008, while serum vitamin B12 concentration increased only in older adults. B-complex supplement use raised in 2015, reflecting in serum vitamins status. Overall serum vitamin B12 deficiencies (<200 pg/mL) were 23.2% and 21.2%, while serum folate deficiencies (<4 ng/mL) were 4.1% and 1.5% in 2008 and 2015, respectively. The lowest quintile of serum folate (≤8.7 ng/mL) was positively associated with smoking and oral contraceptive use, while the highest quintile (≥17.8 ng/mL) was inversely associated with smoking and positively with B-complex supplement use. The odds of having vitamin B12 deficiency was inversely associated with B-complex supplement use, higher serum folate median, higher dietary vitamin B12 intake and positively associated with using oral contraceptive.

CONCLUSION

Overall deficiency of folate has decreased in 2015, being almost non-existent. Low vitamin B12 status presented similar proportions in the overall population comparing both periods, except for older adults. Different predictive variables were identified to better understand vitamins status outcomes in the most recent period of the study.

Plasma Cotinine Is Positively Associated with Homocysteine in Smokers but Not in Users of Smokeless Tobacco

Plasma total homocysteine (tHcy) is a risk marker, and smoking is an established risk factor for cardiovascular disease. It is unclear if the effect of smoked tobacco on homocysteine is mediated by nicotine or other combustion products in smoked tobacco. Snus (moist smokeless tobacco) is high nicotine-containing tobacco, and little is known about the effect of snus on plasma homocysteine. Therefore, we studied, in a cross-section of subjects (n = 1375) from the Northern Sweden Health and Disease Study, with strictly defined current smokers (n = 194) and snus users (n = 47), the impact of tobacco exposure on tHcy, assessed by self-reported tobacco habits and plasma cotinine concentrations. The snus users had higher cotinine concentrations than the smokers. Cotinine, creatinine, methylmalonic acid, and the methylenetetrahydrofolate reductase genotype (MTHFR) T allele were positively associated with tHcy among the smokers, but not among the snus users. No association was observed between tHcy and the number of cigarettes/day. There was a positive association between cotinine and tHcy in the smokers, but not among the snus users. This indicates that substances other than nicotine in tobacco smoke could be responsible for the differential effects on homocysteine status. Self-reported smoking should be complemented by a cotinine assay whenever possible.

Dietary Intake of Folate and Assessment of the Folate Deficiency Prevalence in Slovenia Using Serum Biomarkers

Folate deficiency is associated with various health issues, including anemia, cardiovascular disease, and birth defects. Low folate intake and suboptimal folate status were found in several countries; however, this topic has not yet been investigated in Slovenia. Dietary folate intake and serum folate status were investigated through the nationally representative food consumption study SI.Menu/Nutrihealth. Folate intake was estimated using a sample of N = 1248 subjects aged 10–74 years, stratified in three age groups (adolescents, adults, elderly population), through two 24 h-dietary recalls and food propensity questionnaire. Data on serum folate and homocysteine was available for 280 participants. Very low folate intake (<300 µg/day) was observed in 59% of adolescents, 58% of adults and 68% of elderlies, and only about 12% achieved the WHO recommended level of 400 µg/day. Major dietary contributors were vegetables and fruit, and cereal products. Living environment, education, employment status and BMI were linked with low folate intake in adults; BMI, and sex in adolescents; and sex in elderlies. Considering low serum folate (<7 nmol/L) and high serum homocysteine (>15 nmol/L), folate deficiency was found in 7.6 and 10.5% in adults and elderlies, respectively. Additional public health strategies should be employed to promote the consumption of folate-rich foods. With current folate intakes, supplementation with folic acid is relevant especially in specific vulnerable populations, particularly in women planning and during pregnancy.

A Retrospective Cross-Sectional Cohort Trial Assessing the Prevalence of MTHFR Polymorphisms and the Influence of Diet on Platinum Resistance in Ovarian Cancer Patients

Ovarian cancer has the lowest survival rate in gynaecologic malignancies with a 5-year survival rate of 43%. Platinum resistance is one of the main drivers of ovarian cancer mortality, of which aberrant methylation has been cited as a significant contributor. Understanding the essential role of the methylenetetrahydrofolate reductase enzyme (MTHFR) on DNA synthesis and repair, and how nutrient status can vastly affect its performance, led to the investigation of MTHFR status and dietary influence on platinum response in epithelial ovarian cancer (EOC) patients. Twenty-five adult female patients who completed first-line platinum-based chemotherapy for primary ovarian cancer were selected from Icon Cancer Centres in Australia. Participants were grouped based on platinum response. A full medical and family history, food frequency questionnaire and single blood test were completed, testing for MTHFR polymorphisms, serum folate, serum and active B12 and homocysteine levels. Nineteen of twenty-five participants had an MTHFR polymorphism. Of those, 20% were compound heterozygous, 12% were heterozygous C677T (CT), 4% homozygous C677T, 12% homozygous A1298C and 28% were heterozygous A1298C (AC). Statistically significant associations were found between dietary zinc (p = 0.0086; 0.0030; 0.0189) and B12 intakes in CT genotypes (p = 0.0157; 0.0030; 0.0068) indicating that zinc or vitamin B12 intakes below RDI were associated with this genotype. There were strong associations of vitamin B6 intakes in AC genotypes (p = 0.0597; 0.0547; 0.0610), and dietary folate in compound heterozygotes with sensitive and partially sensitive disease (p = 0.0627; 0.0510). There were also significant associations between serum folate (p = 0.0478) and dietary B12 (p = 0.0350) intakes above RDI and platinum sensitivity in wild-types as well as strong associations with homocysteine levels (p = 0.0886) and zinc intake (p = 0.0514). Associations with dietary B12 (p = 0.0514) and zinc intakes (p = 0.0731) were also strong in resistant wild types. Results indicate that dietary zinc, B12 and B6 intakes may be associated with platinum sensitivity dependent on MTHFR genotype. These results require further research to clarify the dosages necessary to elicit a response; however, they provide a novel foundation for acknowledging the role of diet on treatment response in EOC.

Novel predictive risk factor for Erectile Dysfunction: Serum folic acid

The purpose of this study was to compare the serum Folic Acid (FA) levels in patients with Erectile Dysfunction (ED) and healthy controls and whether levels vary with its severity. The study was carried out on 77 sexually active individuals, out of which 41 complained of ED and 36 were apparently normal. Patients were excluded if they had any diseases known to cause ED. The severity was further categorised based on IIEF-5 scores. Blood serum levels of testosterone, lipid profile, random blood sugar, liver function test, renal function test and FA levels were obtained in each patient. Independent-samples t test of significance was used when comparing between two means. Pearson's correlation coefficient (r) test was used for correlating data. All clinical and biochemical parameters except FA were comparable in both the groups. FA levels were significantly decreased in ED group (5.29 vs. 10.8; p value = .004). Smoking habits were comparable between the groups, and FA levels did not vary among smokers and nonsmokers (p value = .46). Serum FA levels significantly declined with increasing severity of ED (8.28 vs. 5.56 vs. 4.37 vs. 3.5; p value < .001). Thus, decreased FA might possibly be one of the novel risk factors for ED.

High Serum Folate Concentration Is Associated with Better Lung Function in Male Chronic Obstructive Pulmonary Disease Patients Who Are Current Smokers: Analysis of Nationwide Population-Based Survey

Folate, folic acid, has a role in mitigating inflammatory reactions in the human body. This study aimed to evaluate the association of serum folate levels with lung function in chronic obstructive pulmonary disease (COPD) patients. Of the 8149 participants of the 2016 Korean National Health and Nutrition Examination Survey (KNHANES), 311 subjects (192 males and 119 females) having COPD defined by the lower fifth percentile of the reference population were selected. Pearson's correlation coefficient was used to investigate the relationship between serum folate level and lung function measurements. The association between the serum folate level and lung function in patients with COPD was evaluated using multivariable linear regression analysis after adjustment for age, sex, height, high sensitivity C-reactive protein, total calorie intake, residence, smoking status and smoking pack-years, education, and household income. The serum folate level showed a positive correlation with the predicted percentage of forced expiratory volume in one second (FEV₁%). In males, a trend for a positive correlation with serum folate level was observed in predicted FEV₁%, FEV₁ value, predicted percentage of forced vital capacity (FVC%), FVC value, and peak expiratory flow (PEF). No significant correlation between the serum folate level and lung function in females was observed. In the multivariable linear regression model, the serum folate level was associated with an increase in predicted FEV1%, FEV₁ value, predicted FVC%, FVC value, and PEF; however, the significance was only observed in males, especially among current smokers. High serum folate level was positively associated with lung function measurements in male COPD patients who were current smokers. Further longitudinal studies are needed to elucidate the underlying mechanisms.

Interaction Effects of Plasma Vitamins A, E, D, B9, and B12 and Tobacco Exposure in Urothelial Bladder Cancer: A Multifactor Dimensionality Reduction Analysis

The study aimed to examine circulating vitamins A, E, D, and B12 and folate in patients with urothelial bladder cancer (UBC) and detect potential interaction effects of these micronutrients on UBC risk. A case-control study was conducted on 262 UBC patients and 254 matched controls. Vitamins A and E were assessed by ultra performance liquid chromatography, and vitamins D and B12 and folate were assessed by immunological methods. Binary logistic regression models were used to test associations of plasma vitamins tertiles with UBC risk. A multifactor dimensionality reduction method (MDR) was applied to assess interactive effects of the vitamins and tobacco on UBC risk. Higher levels in vitamins A, E, and D were associated with lower occurrence of UBC. No significant association was observed in plasma folate or vitamin B12 with UBC. There were redundancy interactions of plasma vitamin D with tobacco and with plasma vitamin A on UBC risk. Even though the study could not ascertain causality, the findings suggest that vitamins A, E, and D might be protective against UBC. Vitamins A and D interact antagonistically with each other's and with tobacco to modulate UBC risk. These interactions should be taken in consideration for the prevention of UBC.

Low serum folic acid can be a potential independent risk factor for erectile dysfunction: a prospective case-control study

PURPOSE

The purpose of the study was to compare serum level of folic acid (FA) in patients with erectile dysfunction (ED) versus healthy controls and to assess its correlation with other well-known confounders for ED.

METHODS

Our prospective study compared FA in 60 patients with ED versus 30 healthy controls. Patients were excluded if they had any hormonal disorders, Peyronie's disease, or decompensated systemic illnesses. ED was evaluated by the validated Arabic version of the abbreviated five-item form of the International Index Of Erectile Function and confirmed by penile duplex. Serum FA level was assayed using ELIZA. Mann-Whitney, Kruskal-Wallis, and Chi-square tests and Spearman correlation were used as appropriate and confirmed by logistic regression model.

RESULTS

Our study revealed that the median FA of the cases and the controls were 7.1 ng/mL and 13.4 ng/mL, respectively, and this difference was of high statistical significance (p < 0.001). Moreover, our study demonstrated significant relations between serum FA with DM, HTN, smoking, age, and cholesterol (p 0.01, 0.03, 0.014, 0.001, and 0.015, respectively). Our study showed that the best cut-off point of serum FA to detect patients with ED was found to be ≤ 9.42 with sensitivity of 80.00%, specificity of 93.33% and area under curve (AUC) of 91.3%.

CONCLUSION

Serum FA level decreased as the severity of ED increased even after adjustment of age, serum testosterone, DM, HTN, and smoking. FA deficiency might be an independent risk factor of ED.

The Relevance of Vitamin and Iron Deficiency in Patients with Inflammatory Bowel Diseases in Patients of the Swiss IBD Cohort

BACKGROUND ANDAIMS

Vitamin and iron deficiencies are common in patients with inflammatory bowel disease (IBD) as a result of chronic intestinal inflammation, increase in demand, or dietary restrictions. Here, we assessed the frequency of complications in relation to deficiency of iron, folate acid, and vitamin B12 in patients enrolled in the nationwide Swiss Inflammatory Bowel Disease Cohort Study (SIBDCS).

METHODS

A total of 2666 patients were included in the study, 1558 with Crohn's disease (CD) and 1108 with ulcerative colitis (UC).

RESULTS

Iron deficiency anemia was detected in 19.6% of CD patients and 21.6% of UC patients. In CD patients low BMI and nonsmoker status were positively associated with anemia. In both CD and UC, malabsorption syndrome, defined as failure of the GI tract to absorb 1 or more substances from the diet, was found to be significantly associated with anemia (6.2% and 3.8%, respectively) and current steroid use (40% CD, 52.7% UC). In CD patients with ileal (31.7% vs 20%) and colonic (29.9% vs 25%) disease location folate deficiency was significantly higher than in patients with ileocolonic CD or upper GI involvement. In CD patients, vitamin B12 deficiency was associated with the onset of stenosis and intestinal surgery (42.9% vs 32.8% and 46% vs 33% for patients with versus without B12 deficiency).

CONCLUSION

Our data indicate that due to frequent occurrence of deficiency states, regular monitoring and substitution of vitamins and iron are mandatory and may prevent long-term intestinal and extraintestinal complications in IBD patients.

Analysis of Short-Term Smoking Effects in PBMC of Healthy Subjects-Preliminary Study

Early structural changes exist in the small airways before the establishment of Chronic Obstructive Pulmonary Disease (COPD). These changes are believed to be induced by oxidation. The aim of this study was to analyze the influence of short-term smoking on the expression of the genes contributing to airway remodeling and their relationship with the oxidative status of human blood cells. Blood mononuclear cells were isolated from 16 healthy volunteers and treated with cigarette smoke ingredients (CSI): nicotine, 1-Nitrosodimethylamine, N-Nitrosopyrrolidyne, vinyl chloride, acetone, and acrolein. The expression of TGF-β1, TIMP-1, SOD1, and arginase I was determined by qPCR. Additionally, thiol groups and TBARs were assessed. CSI induced TGF and TIMP-1 expression in peripheral blood mononuclear cells (PBMC), and apocynin alleviated this effect. The changes were more noticeable in the smoking group (p < 0.05). TBARs concentrations were higher in smokers, and in this group, apocynin acted more effectively. SOD1 correlated with arginase expression in smokers (p < 0.05). MMP-9 showed a significant correlation with SOD1 in both groups, but only on the protein level. Blood cells appear to mirror the general changes caused by cigarette smoke ingredients, which seem to be connected with the oxidative status of the cell. Our findings indicate that a short period of smoking influences the gene expression and oxidative balance of blood cells, which might result in the development of serious disorders such as COPD.

Determinants of folate and vitamin B12 plasma levels in the French E3N-EPIC cohort

PURPOSE

Impaired B vitamin status has been identified as a risk factor for major chronic diseases. This study aims at examining the determinants of plasma folate and vitamin B12 concentrations, considering lifestyle factors and MTHFR polymorphisms.

METHODS

A total of 988 women aged 40-65 years from the French E3N cohort were investigated. Intakes of folate and vitamin B12 were assessed using food frequency questionnaires, and plasma concentrations were measured by microbiological assay. Dietary scores were computed to summarize folate and vitamin B12 dietary sources. MTHFR-C677T and MTHFR-A1298C were determined by Kaspar assay. Pearson's partial correlation coefficients and multivariable linear regression models were used to assess correlations between main determinants and plasma folate and vitamin B12 levels.

RESULTS

The partial correlation coefficient between dietary intakes and plasma folate was 0.19 (p value <0.001) and 0.08 (p value = 0.008) for vitamin B12. Dietary scores were the main determinant of B vitamin plasma concentrations with a percent change per unit increase of 12.64% (p value <0.001) for folate and 7.6% (p value <0.001) for vitamin B12. Homozygous (T/T) or heterozygous (C/T) women for MTHFR-C677T had lower plasma folate concentrations [C/T: -6.48% (p value = 0.038) and T/T: -15.89% (p value <0.001)] compared to women carrying the C/C genotype. Other determinants of B vitamin plasma concentration include: smoking status for folate, and age and hormone replacement therapy for vitamin B12.

CONCLUSIONS

We confirmed previous findings on the role of diet as main determinant of folate and vitamin B12 plasma concentrations. However, the impact of genetic polymorphisms and lifestyle factors on plasma B vitamin concentrations should not be neglected.

Review of biomarkers to assess the effects of switching from cigarettes to modified risk tobacco products

Context: One approach to reducing the harm caused by cigarette smoking, at both individual and population level, is to develop, assess and commercialize modified risk alternatives that adult smokers can switch to. Studies to demonstrate the exposure and risk reduction potential of such products generally involve the measuring of biomarkers, of both exposure and effect, sampled in various biological matrices.Objective: In this review, we detail the pros and cons for using several biomarkers as indicators of effects of changing from conventional cigarettes to modified risk products.Materials and methods: English language publications between 2008 and 2017 were retrieved from PubMed using the same search criteria for each of the 25 assessed biomarkers. Nine exclusion criteria were applied to exclude non-relevant publications.Results: A total of 8876 articles were retrieved (of which 7476 were excluded according to the exclusion criteria). The literature indicates that not all assessed biomarkers return to baseline levels following smoking cessation during the study periods but that nine had potential for use in medium to long-term studies.Discussion and conclusion: In clinical studies, it is important to choose biomarkers that show the biological effect of cessation within the duration of the study.

Folate intake in a Swedish adult population: Food sources and predictive factors

Introduction: Folate plays an important role in cell metabolism, but international studies show that intake is currently below recommendations, especially among women. The study objective was to identify folate food sources by food group, gender, and age group, and to identify factors influencing folate intake, based on food consumption data for Swedish adults in the 2010–11 Riksmaten study.

Methods: The sample included a representative Swedish population aged 18–80 years (n = 1657; 56.3% female). Food and nutrient intakes were estimated from self-reported food records during 4 consecutive days. Food consumption was categorized into 26 food groups. Stepwise regression was used to analyze food groups as folate sources for participants. Factors predicting the highest folate intake (third tertile) were determined by logistic regression analysis.

Results: Vegetables and pulses represented the most important folate source for all age groups and both genders, especially in women aged 45–64 years (49.7% of total folate intake). The next folate source in importance was dairy products for the youngest group (18–30 years), bread for men, and fruit and berries for women. The likelihood of being in the highest tertile of folate intake (odds ratio = 1.69, 95% confidence interval 1.354–2.104) was higher for men. Influencing factors for folate intake in the highest tertile were low body mass index and high educational level in the men, and high educational level, vegetarian diet, organic product consumption, non-smoking, and alcohol consumption within recommendations in the women.

Conclusion: This study describes the folate intake per food group of Swedish adults according to the 2010–11 Riksmaten survey, identifying vegetables and pulses as the most important source. Data obtained on factors related to folate consumption may be useful for the development of specific nutrition education programs to increase the intake of this vitamin in high-risk groups.

Diet, life-style and cardiovascular morbidity in the rural, free living population of Elafonisos island

BACKGROUND

There are about 70 small islands in the Aegean and Ionian Sea, of less than 300 Km2 and 5000 inhabitants each, comprising a total population of more than 75,000 individuals with geographical and socioeconomic characteristics of special interest. The objective of the present study was to assess lifestyle characteristics and the state of cardiovascular risk of the population of a small Eastern Mediterranean island, Elafonisos.

METHODS

PERSEAS (Prospective Evaluation of cardiovascular Risk Surrogates in Elafonisos Area Study) is an ongoing, population-based, longitudinal survey of cardiovascular risk factors, life-style characteristics and related morbidity/mortality performed in a small and relatively isolated island of the Aegean Sea, named Elafonisos. Validated, closed-ended questionnaires for demographic, socio-economic, clinical and lifestyle characteristics were distributed and analyzed. The MedDietScore, a validated Mediterranean diet score was also calculated. In addition, all participants underwent measurement of anthropometric parameters, blood pressure and a full blood panel for glucose and lipids.

RESULTS

The analysis included 596 individuals who represented 74.5% of the target population. The mean age of the population was 49.5 ± 19.6 years and 48.2% were males. Fifty participants (8.4%) had a history of cardiovascular disease (CVD). The rates of reported diabetes, hypertension, and hypercholesterolemia were 7.7%, 30.9% and 30.9% respectively, with screen-detection of each condition accounting for an additional 4.0%, 12.9%, and 23.3% of cases, respectively. Four hundred and seven individuals (68.3%) were overweight or obese, 25% reported being physically inactive and 36.6% were active smokers. The median MedDietScore was 25 [interquartile range: 6, range 12-47] with higher values significantly associated with older age, better education, increased physical activity, absence of history of diabetes and known history of hypercholesterolemia.

CONCLUSIONS

Obesity and traditional risk factors for CVD are highly prevalent among the inhabitants of a small Mediterranean island. Adherence to the traditional Mediterranean diet in this population is moderate, while physical activity is low. There seems to be a need for lifestyle modification programs in order to reverse the increasing cardiovascular risk trends in rural isolated areas of the Mediterranean basin.

Predictors of folate status among pregnant Japanese women: the Hokkaido Study on Environment and Children’s Health, 2002–2012

The International Clearinghouse for Birth Defects, Surveillance and Research reports a rise in the prevalence rate of spina bifida in Japan. We determined first-trimester folate status of Hokkaido women and identified potential predictors. Participants were 15 266 pregnant women of the Hokkaido Study on Environment and Children’s Health Cohort. Data were extracted from self-reported questionnaires and biochemical assay results. Demographic determinants of low folate status were younger maternal age (adjusted OR (AOR) 1·48; 95 % CI 1·32, 1·66), lower educational level (AOR 1·27; 95 % CI 1·17, 1·39) and lower annual income (AOR 1·11; 95 % CI 1·01, 1·22). Plasma cotinine concentrations of 1·19–65·21 nmol/l increased the risk of low folate status (AOR 1·20; 95 % CI 1·10, 1·31) and concentrations >65·21 nmol/l further increased the risk (AOR 1·91; 95 % CI 1·70, 2·14). The most favourable predictor was use of folic acid (FA) supplements (AOR 0·19; 95 % CI 0·17, 0·22). Certain socio-demographic factors influence folate status among pregnant Japanese women. Modifiable negative and positive predictors were active and passive tobacco smoking and use of FA supplements. Avoiding both active and passive tobacco smoking and using FA supplements could improve the folate status of Japanese women.

A single blueberry (Vaccinium corymbosum) portion does not affect markers of antioxidant defence and oxidative stress in healthy volunteers following cigarette smoking

We previously reported that a portion of blueberries reversed endothelial dysfunction induced by acute cigarette smoking. Since smoking-induced endothelial dysfunction is associated with a condition of oxidative stress, we evaluated whether the observed effect was mediated by modulation of markers of oxidative stress and antioxidant defence. Fourteen out of 16 male healthy smokers previously enrolled, participated in a three-armed randomized controlled study with the following experimental conditions: smoking treatment (one cigarette); blueberry treatment (300g of blueberries) + smoking (one cigarette); control treatment (300ml of water with sugar) + smoking (one cigarette). The cigarette was smoked 100min after blueberry/control/water consumption. Each treatment was separated by 1 week of washout period. Plasma vitamin (C, B12 and folate) and aminothiol concentrations, endogenous [formamidopyrimidine-DNA glycosylase (FPG)-sensitive sites] and oxidatively induced DNA damage (resistance to H2O2-induced DNA damage) in peripheral blood mononuclear cells (PBMCs) were measured at baseline and 20, 60, 90, 120min and 24h after smoking. On the whole, analysis of variance did not show a significant effect of treatment on the modulation of markers of oxidative stress and antioxidant defence but revealed an effect of time for plasma concentrations of vitamin C (P = 0.003), B12 (P < 0.001), folate (P < 0.001), total cysteine (P = 0.007) and cysteine-glycine (P = 0.010) that increased following the three treatments after smoking. No significant effect of treatment was observed for the levels of FPG-sensitive sites (P > 0.05) and H2O2-induced DNA damage (P > 0.05) in PBMCs. In conclusion, the consumption of a single blueberry portion failed to modulate markers of oxidative stress and antioxidant defence investigated in our experimental conditions. Further studies are necessary to elucidate this finding and help clarifying the mechanisms of protection of blueberries against smoking-induced endothelial dysfunction.

Mechanisms of action for arsenic in cardiovascular toxicity and implications for risk assessment

The possibility of an association between inorganic arsenic (iAs) exposure and cardiovascular outcomes has received increasing attention in the literature over the past decade. The United States Environmental Protection Agency (US EPA) is currently revising its Integrated Risk Assessment System (IRIS) review of iAs, and one of the non-cancer endpoints of interest is cardiovascular disease (CVD). Despite the increased interest in this area, substantial gaps remain in the available information, particularly regarding the mechanism of action (MOA) by which iAs could cause or exacerbate CVD. Few studies specifically address the plausibility of an association between iAs and CVD at the low exposure levels which are typical in the United States (i.e., below 100 μg As/L in drinking water). We have conducted a review and evaluation of the animal, mechanistic, and human data relevant to the potential MOAs of iAs and CVD. Specifically, we evaluated the most common proposed MOAs, which include disturbance of endothelial function and hepatic dysfunction. Our analysis of the available evidence indicates that there is not a well-established MOA for iAs in the development or progression of CVD. Few human studies of the potential MOAs have addressed plausibility at low doses and the applicability of extrapolation from animal studies to humans is questionable. However, the available evidence indicates that regardless of the specific MOA, the effects of iAs on physiological processes at the cellular level appear to operate via a threshold mechanism. This finding is consistent with the lack of association of CVD with iAs exposure in humans at levels below 100 μg/L, particularly when considering important exposure and risk modifiers such as nutrition and genetics. Based on this analysis, we conclude that there are no data supporting a linear dose-response relationship between iAs and CVD, indicating this relationship has a threshold.

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.

Prediction of methotrexate clinical response in Portuguese rheumatoid arthritis patients: implication of MTHFR rs1801133 and ATIC rs4673993 polymorphisms

Objective. Methotrexate (MTX), the most used drug in rheumatoid arthritis (RA) treatment, showing variability in clinical response, is often associated with genetic polymorphisms. This study aimed to elucidate the role of methylenetetrahydrofolate reductase (MTHFR) C677T and aminoimidazole carboxamide adenosine ribonucleotide transformylase (ATIC) T675C polymorphisms and clinicopathological variables in clinical response to MTX in Portuguese RA patients. Methods. Study included 233 RA patients treated with MTX for at least six months. MTHFR C677T and ATIC T675C polymorphisms were genotyped and clinicopathological variables were collected. Statistical analyses were performed and binary logistic regression method adjusted to possible confounding variables. Results. Multivariate analyses demonstrated that MTHFR 677TT (OR = 4.63; P = 0.013) and ATIC 675T carriers (OR = 5.16; P = 0.013) were associated with over 4-fold increased risk for nonresponse. For clinicopathological variables, noncurrent smokers (OR = 7.98; P = 0.001), patients positive to anti-cyclic citrullinated peptide (OR = 3.53; P = 0.004) and antinuclear antibodies (OR = 2.28; P = 0.045), with higher health assessment questionnaire score (OR = 2.42; P = 0.007), and nonsteroidal anti-inflammatory drug users (OR = 2.77; P = 0.018) were also associated with nonresponse. Contrarily, subcutaneous administration route (OR = 0.11; P < 0.001) was associated with response. Conclusion. Our study suggests that MTHFR C677T and ATIC T675C genotyping combined with clinicopathological data may help to identify patients whom will not benefit from MTX treatment and, therefore, assist clinicians in personalizing RA treatment.

Estimation of serum and erythrocyte folate concentrations in the New Zealand adult population within a background of voluntary folic acid fortification

National data on the blood folate status of New Zealand adults is lacking. The objective of this study was to describe the blood folate status and examine the predictors of blood folate status in a national sample of adults from New Zealand, a country with voluntary folic acid fortification. The 2008/09 New Zealand Adult Nutrition Survey was a nationwide multistage systematic random cross-sectional survey. Serum and erythrocyte folate concentrations were measured by microbiologic assay. The survey included 4721 participants aged ≥15 y, 3359 of whom provided a nonfasting blood sample. Biochemical folate status was measured in 3277 participants. The median serum and erythrocyte folate concentrations were 23 and 809 nmol/L, respectively. The prevalence of biochemical folate deficiency, defined as plasma folate <6.8 nmol/L or erythrocyte folate <305 nmol/L, was 2%. Having breakfast daily compared with never eating breakfast was associated with 53% higher serum and 25% higher erythrocyte folate concentrations; consumers of fortified yeast extract spread had 17% higher serum and 14% higher erythrocyte folate concentrations than nonconsumers; daily users of folate-containing supplements compared with nonusers had 48% higher serum and 28% higher erythrocyte folate concentrations. The prevalence of biochemical folate deficiency in New Zealand adults is low. Participants who ate breakfast more frequently, consumed folate-fortified yeast, or used a daily folate supplement had higher blood folate concentrations.

Folate intake and folate serum levels in men and women from two European populations: The IMMIDIET project

OBJECTIVE

Folate status has been associated with neural tube defects and cerebrovascular disease. The aim of this study was to evaluate possible differences in folate status in two European Union countries and to assess their possible association with dietary patterns and/or other lifestyles.

METHODS

In the framework of the European Union-funded IMMIDIET Project, 1068 individuals (534 male-female pairs), ages 26 to 64 y, were enrolled in Italy and the United Kingdom. One-year-recall food frequency questionnaire was used to evaluate dietary intake. Reduced rank regression analysis was used to derive a dietary pattern better describing high dietary folate intake.

RESULTS

Of the total participants, 11.3% of the Italians and 45.1% of the British exceeded the optimal dietary folate intake of 400 μg/d (Recommended Dietary Allowance). Of the women, 66.7% and 22.1% of Italian and British women, respectively, all at childbearing age, had folate serum levels <6.62 ng/mL (P = 0.01). The percentage of total variance of dietary folate intake explained by food group consumption was 14.2% and 16.3% in Italy and the United Kingdom, respectively. Reduced rank regression analysis indicated a healthy pattern that was positively associated with folate serum levels in both countries (for all β-coefficients >0; P < 0.001): 100 μg/d increase in dietary folate intake was associated with 13.8% and 10.5% increase in folate serum levels in the Italian and British population, respectively (for 100 μg/d increase e(β-coef) = 1.138 and 1.105; P < 0.001). Smoking habit was negatively but physical activity positively associated with folate serum levels (P < 0.05).

CONCLUSIONS

An inadequate dietary folate intake and subsequent serum levels were observed in the Italian participants. High consumption of food sources of folate was positively associated with folate serum levels, explaining a good proportion of its variability.

Smoking and dietary inadequacy among Inuvialuit women of child bearing age in the Northwest Territories, Canada

Objective

The prevalence of smoking in Aboriginal Canadians is higher than non-Aboriginal Canadians, a behavior that also tends to alter dietary patterns. Compared with the general Canadian population, maternal smoking rates are almost twice as high. The aim of this study was to compare dietary adequacy of Inuvialuit women of childbearing age comparing smokers versus non-smokers.

Research methods & procedures

A cross-sectional study, where participants completed a culturally specific quantitative food frequency questionnaire. Non-parametric analysis was used to compare mean nutrient intake, dietary inadequacy and differences in nutrient density among smokers and non-smokers. Multiple logistic regression analyses were performed for key nutrients inadequacy and smoking status. Data was collected from three communities in the Beaufort Delta region of the Northwest Territories, Canada from randomly selected Inuvialuit women of childbearing age (19-44 years).

Results

Of 92 participants, 75% reported being smokers. There were no significant differences in age, BMI, marital status, education, number of people in household working and/or number of self employed, and physical activity between smokers and non-smokers. Non-parametric analysis showed no differences in nutrient intake between smokers and non-smokers. Logistic regression however revealed there was a positive association between smoking and inadequacies of vitamin C (OR = 2.91, 95% CI, 1.17-5.25), iron (OR = 3.16, 95% CI, 1.27-5.90), and zinc (OR = 2.78, 95% CI, 1.12-4.94). A high percentage of women (>60%), regardless of smoking status, did not meet the dietary recommendations for fiber, vitamin D, E and potassium.

Conclusions

This study provides evidence of inadequate dietary intake among Inuvialuit of childbearing age regardless of smoking behavior.

Association between biomarker-quantified antioxidant status during pregnancy and infancy and allergic disease during early childhood: a systematic review

Recent findings suggest a significant association between the antioxidant status of pregnant women and of their children during the first years of life and the development of allergic disease during childhood. The aim of this review was to identify all studies that estimated the effect of intake of antioxidants in pregnant women and their children on the development of allergic disease during early childhood. A systematic review was conducted of epidemiological studies featuring original peer-reviewed data on the association between dietary antioxidant status and allergic disease during childhood. A systematic search was performed following the Meta-analysis of Observational Studies in Epidemiology Guidelines. A comprehensive search of the literature yielded 225 studies, 18 of which were selected for the extraction of results and were related to antioxidant status and allergic disease. The systematic review included five prospective cohort studies, four cross-sectional studies, and nine case-control studies. Eight studies reported an important association between antioxidant status and asthma onset during childhood. Similarly, wheezing and eczema were studied as an outcome in six and in five studies, respectively. Recent observational studies suggest that a higher intake of antioxidant vitamins, zinc, and selenium during pregnancy and childhood reduces the likelihood of childhood asthma, wheezing, and eczema.

Healthcare-related characteristics of low vs normal folate levels among women of child-bearing age

OBJECTIVE

Despite the institution of mandatory folic acid fortification in the US, folate deficiencies still occur and are associated with an increased risk of several conditions. Since little is known regarding the relationship between folate status and other clinical, demographic, and healthcare-related characteristics, the objective of the study was to compare healthcare-related characteristics among US child-bearing age women with low vs normal red blood cell (RBC) folate levels.

RESEARCH DESIGN AND METHODS

Data from the 2003-2006 National Health and Nutrition Examination Survey (NHANES) were used to conduct a retrospective cohort study. Women (aged 18-45 when surveyed) were categorized in two cohorts for comparison: normal RBC folate level (≥ 140 ng/ml, NFL) and low RBC folate level (<140 ng/ml, LFL).

RESULTS

Of the 2816 subjects, 5.9% were assigned to the LFL cohort and were significantly younger (28 vs 30 years, p=0.01); a greater proportion were 18-25 years old (55.7% vs 39.9%, p<0.001) or African-American (55.1% vs 22.3%, p<0.01). A lower proportion of LFL women were insured (67.3% vs 75.5%, p=0.01) with low rates of private insurance (39.5% vs 53.1%, p<0.01), while Medicaid/SCHIP coverage was similar (16.8% vs 15.1%, p=0.56). Predictors of low folate levels included aged 36-45 years (OR: 2.14 [95% CI: 1.04, 4.39]) and never being married (2.65 [1.34, 5.24]), while a household income ≥ $75,000 reduced the likelihood of having low folate levels (0.20 [0.06, 0.73]).

LIMITATIONS

The proportion of women with low folate levels was small, with the sample size limiting the ability to adjust for other factors during analysis. Medical histories were based on patient interviews and are subject to recall bias.

CONCLUSION

LFL women are younger and have low rates of private insurance coverage compared to women with normal folate levels. Differences in age, marital status, and household income are associated with folate status.

Does adherence to the Mediterranean diet have a protective effect against active and passive smoking?

OBJECTIVE

To investigate the existing evidence about whether adherence to the Mediterranean diet may have a role as an effect modifier of active and passive smoking on human health.

STUDY DESIGN

Review.

METHODS

An overview of emerging evidence and published studies that cover the interaction between the Mediterranean diet and smoking.

RESULTS

Both epidemiological and laboratory studies have shown that the Mediterranean diet has a protective effect against biochemical and molecular processes that lead to cancer, cardiovascular disease and respiratory illness. Based on the high daily intake of vitamins and antioxidants, the Mediterranean diet is comprised of a number of compounds that could alter certain outcomes related to smoking. Studies have indicated that certain diseases attributable to smoking, such as lung cancer, asthma and cardiovascular disease, are inversely associated with certain antioxidants and lipids.

CONCLUSIONS

The literature indicates that the existence of a partial interaction between adherence to the Mediterranean diet and the health effects of smoking is possible. Further research is needed to lead to a conclusive statement on this hypothesis.

Effect of cigarette smoking on plasma homocysteine concentrations

BACKGROUND

Cigarette smoking has been recognized as a major risk factor for cardiovascular disease, while the role of homocysteine is still not clear. This study investigated the effects of smoking on plasma homocysteine concentration and determined the correlation between this parameter and biological markers of tobacco use, such as plasma thiocyanate and urine cotinine.

METHODS

Folate, vitamin B12 and homocysteine were measured in 300 subjects: 138 non-smokers and 162 smokers using immunoassay methods. Cotinine was measured using an enzymatic colorimetric method and thiocyanate by a selective electrode.

RESULTS

In smokers, we found a significant increase in homocysteine and a decrease in folate and vitamin B12 levels compared to non-smokers. Homocysteine was strongly correlated with the duration of use and the number of cigarettes consumed. Folate and vitamin B12 were significantly reduced in subjects smoking for more than 20 years compared to those who smoked less than 5 years. Among smokers, we noted a positive correlation between homocysteine and both plasma thiocyanates and cotininuria, and a negative-correlation between cotininuria and plasma folate.

CONCLUSIONS

Cigarette smoking increases homocysteine, which is strongly correlated with cotininuria and plasma thiocyanates. Moreover, smokers had tendency to develop hypofolatemia and hypovitamin B12, particularly when the duration of consumption exceeded 20 years.

Cardiovascular disease risk factors and dietary habits of farmers from Crete 45 years after the first description of the Mediterranean diet

BACKGROUND

Farmers from Crete as first studied within the framework of the Seven Countries Study, were historically known for holding the title of the 'gold standard' of health status globally and had a very low prevalence of both cardiovascular disease (CVD) and cancer. Taking the above into account we evaluated the changes in CVD risk factors among farmers in Crete, Greece and compared our findings with data from the 1960s.

DESIGN

Cross-sectional.

METHODS

Five hundred and two farmers (18-79 years old) from the Valley of Messara in Crete were randomly selected and examined in 2005. Complete clinical, biochemical, dietetic, anthropometrical and lifestyle CVD risk factors were assessed, matched and compared with published data from the 1960s.

RESULTS

In comparison with 45 years ago, present day male farmers from Crete were found to have a 30% higher BMI (29.8 vs. 22.9 kg/m, P<0.001) and a 16% higher total cholesterol level (239.6 vs. 206.9 mg/dl, P<0.001) and also a not so favourable daily dietary intake (increase in meat and saturated fat and decrease in fruit, P<0.001, respectively), while a significant reduction in systolic blood pressure and energy intake was noticed. In regards to changes in subcutaneous adipose tissue fatty acid composition, a decrease in monounsaturated (P<0.001) and an increase in saturated fatty acids (P<0.001) was also found elucidating the temporal change in dietary habits.

CONCLUSION

The population's lack of adherence to the Mediterranean diet, have led to the fact that currently farmers from Crete are likely to be at a higher risk for developing CVD in comparison with earlier generations.

Paraoxonase 1 R/Q alleles are associated with differential accumulation of saturated versus 20:5n3 fatty acid in human adipose tissue

Serum paraoxonase 1 (PON1) function has been associated with human cardiovascular disease. The projected mechanism postulates interaction of PON1 with lipoproteins and insulin signaling resulting in alterations in lipid homeostasis. Recently, PON2 was shown to directly regulate triglyceride accumulation in macrophages and PON1 was detected in the interstitial space of adipocytes. The aims of the present study were a) to examine the relationship of the PON1 function with serum parameters related to lipid homeostasis, and b) to examine a possible role of PON1 in the regulation of lipid composition in the human adipose tissue. Two important genetic variations with functional impact on PON1 activity in humans are the Q192R and the L55M. The present study evaluated the impact of the Q192R and the L55M polymorphisms in a cross-section of the population on the island of Crete, as regards to PON1 activity, plasma lipids/lipoproteins, parameters of the metabolic syndrome, and the fatty acid composition of the adipose tissue. We detected a significant association of the polymorphisms with blood pressure, fasting blood glucose, triglycerides, apolipoprotein B, serum iron, and homocysteine. Furthermore, a novel function is suggested for PON1 on the fatty acid composition in the adipose tissue through the positive association of the R allele with saturated fatty acid and of the Q allele with 20:5n3 fatty acid deposition.

Lifestyle and genetic determinants of folate and vitamin B12 levels in a general adult population

Danish legislation regarding food fortification has been very restrictive resulting in few fortified food items on the Danish market. Folate and vitamin B12 deficiency is thought to be common due to inadequate intakes but little is known about the actual prevalence of low serum folate and vitamin B12 in the general population. The aim of the present study was to evaluate the folate and vitamin B12 status of Danish adults and to investigate associations between vitamin status and distinct lifestyle and genetic factors. The study included a random sample of 6784 individuals aged 30–60 years. Information on lifestyle factors was obtained by questionnaires and blood samples were analysed for serum folate and vitamin B12 concentrations and several genetic polymorphisms. The overall prevalence of low serum folate ( < 6·8 nmol/l) was 31·4 %. Low serum folate was more common among men than women and the prevalence was lower with increasing age. Low serum folate was associated with smoking, low alcohol intake, high coffee intake, unhealthy diet, and the TT genotype of the methylenetetrahydrofolate reductase (MTHFR)-C677T polymorphism. The overall prevalence of low serum vitamin B12 ( < 148 pmol/l) was 4·7 %. Low serum vitamin B12 was significantly associated with female sex, high coffee intake, low folate status, and the TT genotype of the MTHFR-C677T polymorphism. In conclusion, low serum folate was present in almost a third of the adult population in the present study and was associated with several lifestyle factors whereas low serum concentrations of vitamin B12 were less common and only found to be associated with a few lifestyle factors.

Prevalence of obesity and physical inactivity among farmers from Crete (Greece), four decades after the Seven Countries Study

BACKGROUND AND AIM

As first shown 40 years ago farmers from Crete had one of the healthiest lifestyles compared to other participants of the Seven Countries Study. Taking the above into account we investigated the prevalence of obesity and its indexes among farmers in Crete in 2005.

METHODS AND RESULTS

502 farmers (18-79 years old) from the Valley of Messara in Crete were randomly selected and examined. Body Mass Index (BMI), waist circumference (WC), waist-to-hip ratio (W/Hip Ratio), waist-to-height ratio (W/Height Ratio), conicity index, percentage of body fat and hours of daily light physical activity (LPhA) and moderate-to-vigorous physical activity (MVPhA) were calculated for each subject. 86,1% of the study population was overweight and/or obese. Specifically 42.9% had a BMI of 25.1-30 kg/m(2) and were overweight and 43.2% were obese with a BMI>30 kg/m(2). The percentage of body fat was estimated at 27.3% of total body weight among males and 39.3% among females, while all obesity indexes were found to differ between genders.

CONCLUSIONS

In comparison to middle aged male farmers from Crete in the 1960s, mean weight has increased by 20 kg (83 kg vs. 63 kg), which has lead to a 7 kg/m(2) in mean BMI (22.9 kg/m(2) vs. 29.8 kg/m(2)), findings that support the fact that the prevalence of obesity in Greece has risen dramatically over the years, even among farmers from Crete, a population historically known for being the gold standard of health status globally.