Folate intakes and folate biomarker profiles of pregnant Japanese women in the first trimester

5,10-Methylenetetrahydrofolate reductase (MTHFR) C677T/A1298C polymorphisms in patients with nonsyndromic cleft lip and palate

Cleft lip with or without cleft palate (CL/P) is considered a multifactorial genetic disorder. Folic acid metabolism has been suggested to underlie the development of CL/P. The gene for the enzyme 5,10-methylentetrahydrofolate reductase (MTHFR) contributes to folic acid metabolism, and polymorphisms of this gene at C677T (rs1801133) and A1298C (rs1801131) are reported to alter its enzyme activity and are suggested to be involved in CL/P development. We investigated C677T and A1298C polymorphisms of the MTHFR gene in Japanese patients with nonsyndromic CL/P and cleft palate only (CPO). We examined 240 patients with CL/P, 103 fathers and 153 mothers of the patients, and 68 healthy controls. Restriction fragment length polymorphisms (RFLPs) of C677T and A1298C of MTHFR were analyzed. We determined the frequencies of the polymorphisms in the patients and controls and performed a transmission equilibrium test and haplotype analysis of both MTHFR C677T and A1298C. There were no significant differences in the frequencies of MTHFR C677T and A1298C polymorphisms between the patients and controls. We did not observe transmission equilibrium or linkage equilibrium among the cases. In this experimental condition, we did not detect an association of MTHFR C677T and/or A1298C polymorphisms with the development of CL/P in this Japanese cohort.

Concentration of folic acid (FA) in serum of Japanese pregnant women

Objectives Exposure to inorganic arsenic (iAs) is a world-wide health concern. We reported that Japanese children and pregnant women are exposed to moderate levels of iAs through food. Reducing iAs contamination from foods of high iAs is an important issue unique in Japan. Integrated iAs is methylated to less toxic organic forms, and S-adenosyl-L-methyonine (SAM), a common methyl-donor of DNA and histones, is utilized in this process. Chronic consumption of SAM by iAs metabolism due to exposure to iAs might alter the epigenetic modification of genome. The SAM biosynthesis pathway is dependent on folate cycle, and it is possible that ingestion of sufficient folic acid (FA) is protective to iAs induced toxicity. Methods In the course of our cross-sectional body burden analyses of Pb and iAs in Japanese children and pregnant women, termed "PbAs study", FA concentration in serum of 104 pregnant women was measured. Results Mean (±SEM) of serum FA concentration was 15.8 ± 1.3 (ng/mL). There are significant number of people showing very high FA (>30 ng/ mL), and large fraction of them were taking supplements daily. Conclusions These results suggested that level of FA ingestion of Japanese pregnant women is high for supporting normal fetal development.

Food intake biomarkers for green leafy vegetables, bulb vegetables, and stem vegetables: a review

BACKGROUND

Numerous studies acknowledged the importance of an adequate vegetable consumption for human health. However, current methods to estimate vegetable intake are often prone to measurement errors due to self-reporting and/or insufficient detail. More objective intake biomarkers for vegetables, using biological specimens, are preferred. The only concentration biomarkers currently available are blood carotenoids and vitamin C, covering total fruit and vegetable intake. Identification of biomarkers for specific vegetables is needed for a better understanding of their relative importance for human health. Within the FoodBAll Project under the Joint Programming Initiative "A Healthy Diet for a Healthy Life", an ambitious action was undertaken to identify candidate intake biomarkers for all major food groups consumed in Europe by systematically reviewing the existent literature. This study describes the review on candidate biomarkers of food intake (BFIs) for leafy, bulb, and stem vegetables, which was conducted within PubMed, Scopus and Web of Science for studies published through March 2019.

RESULTS

In total, 65 full-text articles were assessed for eligibility for leafy vegetables, and 6 full-text articles were screened for bulb and stem vegetables. Putative BFIs were identified for spinach, lettuce, endive, asparagus, artichoke, and celery, but not for rocket salad. However, after critical evaluation through a validation scheme developed by the FoodBAll consortium, none of the putative biomarkers appeared to be a promising BFI. The food chemistry data indicate that some candidate BFIs may be revealed by further studies.

CONCLUSION

Future randomized controlled feeding studies combined with observational studies, applying a non-targeted metabolomics approach, are needed in order to identify valuable BFIs for the intake of leafy, bulb, and stem vegetables.

Folate, vitamin B12, and homocysteine in smoking-exposed pregnant women: A systematic review

Smoking exposure is associated with pregnancy complications, as are levels of folate, vitamin B12, and homocysteine. In nonpregnant adults, smoking exposure is associated negatively with folate and vitamin B12 levels and positively with homocysteine levels. A complete overview of the literature on this topic in pregnant women is lacking. To evaluate evidence of associations of maternal smoking exposure during pregnancy and levels of folate, homocysteine, and vitamin B12 in pregnancy and in cord blood, we searched MEDLINE, Embase, CINAHL, Cochrane, Scopus, Web of Science, and reference lists of relevant studies until August 2017. We selected studies in pregnant women describing the association of passive or active smoking and levels of folate, homocysteine, and/or vitamin B12. Data were extracted by two independent reviewers. We included 32 studies of 2,015 identified references with a total of 37,822 participants and more than 6,000 smokers. Twenty‐eight studies measured folate, 14 measured vitamin B12, and 13 measured homocysteine. Nineteen out of 28 studies assessing folate reported significantly lower levels in pregnant women exposed to smoking compared with those unexposed. Vitamin B12 levels were lower in smoking mothers in eight out of 14 studies. Homocysteine levels tended to be higher in mothers exposed to smoking. Smoking exposure during pregnancy is generally associated with lower folate and vitamin B12 levels and higher homocysteine levels. This may help raise further awareness about the consequences of smoking and the need to encourage stopping smoking in all, especially in pregnant women.

Medical cost savings in Sakado City and worldwide achieved by preventing disease by folic acid fortification

The introduction of mandatory fortification of grains with folate in 1998 in the United States resulted in 767 fewer spina bifida cases annually and a cost saving of $603 million per year. However, far more significant medical cost savings result from preventing common diseases, including myocardial infarction, stroke, dementia and osteoporosis. A cost-effectiveness analysis showed a gain of 266 649 quality-adjusted life-years and $3.6 billion saved annually, mainly due to the reduction of cardiac infarction. The recommended folate intake in Japan is 240 μg/day whereas it is 400 μg/day internationally. Our Sakado Folate Project targeted individuals with genetic polymorphism of methylenetetrahydrofolate reductase or with hyperhomocysteinemia. Using, for example, folate-fortified rice, resulted in an increase in serum folate and a decrease in serum homocysteine in the participants, and reduced medical costs were achieved by decreasing myocardial infarction, stroke, dementia and fracture. Due to the small population of Sakado City (approximately 101 000) and small number of births (693) in 2015, a decrease in spina bifida could not be confirmed but there was a significant decrease in the number of very low birthweight infants. The genome notification of subjects was effective in motivating intake of folate, but the increase in serum folate (from 17.4 to 22.5 nmol/L, 129%) was less than that observed following compulsory folic acid fortification of cereals in the USA (from 12.1 to 30.2 nmol/L, 149.6%). Mandatory folic acid fortification is cheap in decreasing medical costs and is thus recommended in Japan.

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.

Awareness and uptake of measures for preventing CNS birth defects among mothers of affected children in a sub-Saharan African neurosurgeon's practice

BACKGROUND

The two main measures used in the reduction of the birth prevalence of CNS birth defects are (i) folic acid, FA, supplementation/food fortification for reproductively active women as the primary one, and (ii) timely screening/intrauterine diagnosis, and possibly termination of the affected pregnancies.

MATERIALS AND METHODS

We performed a cross-sectional survey of the levels of awareness and uptake of these measures in a consecutive cohort of mothers of children with CNS birth defects presenting for neurosurgical treatment in an African clinical practice.

RESULTS

There were 151 cases, 101 of them neural tube defects, NTDs. The level of awareness of the role of FA in prevention of these defects was low, 18.8%, and dietary multivitamin supplementation was ingested by only10.7% of the study subjects. The mothers' obstetric behavior in the index pregnancies was suboptimal: pregnancy registration and commencement of obstetric supplements were at median gestational age of 4 months, and obstetric ultrasonography was obtained infrequently, and in an unregulated milieu. Only 17.8% of these CNS birth defects were diagnosed prenatally, but >80% of the mothers would have liked to have the intrauterine diagnosis, and about 23% might have asked for termination of these pregnancies.

CONCLUSIONS

The levels of awareness and uptake of measures for preventing CNS birth defects among mothers of affected children in this sub-Saharan African women cohort are low. Interestingly, many of the mothers were very favorably disposed to receiving, and acting on, the information about the screen detected CNS birth defects in their fetuses.

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

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

A systematic review and meta-analysis of micronutrient intakes during pregnancy in developed countries

Micronutrient status during pregnancy influences maternal and fetal health, birth outcomes, and the risk of chronic disease in offspring. Research reporting dietary intake during pregnancy in nationally representative population samples, however, is limited. This review summarizes the micronutrient intakes of pregnant women from developed countries and compares them with relevant national recommendations. A systematic search without date limits was conducted. All studies reporting the micronutrient intakes of pregnant women were considered, irrespective of design. Two authors independently identified studies for inclusion and assessed methodological quality. Nutritional adequacy was summarized, with confounding factors considered. Meta-analysis data are reported for developed countries collectively, by geographical region, and by dietary methodology. Pregnant women in developed countries are at risk of suboptimal micronutrient intakes. Folate, iron, and vitamin D intakes were consistently below nutrient recommendations in each geographical region, and calcium intakes in Japan were below the Japanese recommendations and the average intake levels in other developed countries. Research examining the implications of potential nutrient insufficiency on maternal and offspring health outcomes is needed along with improvements in the quality of dietary intake reporting.

Systematic review and meta-analysis of energy and macronutrient intakes during pregnancy in developed countries

Research reporting diet during pregnancy in nationally representative samples is limited. This review summarizes the dietary intakes of pregnant women in developed countries and compares them with national recommendations. A systematic search without date limits was conducted. All studies reporting the macronutrient intakes of pregnant women were considered, irrespective of design. Two authors independently identified the studies to be included and assessed the methodological quality. Nutritional adequacy was summarized, with confounding factors considered. Meta-analysis data are reported for developed countries collectively, by geographical region, and by dietary methodology. Energy and macronutrient intakes of pregnant women do not match national recommendations. Energy and fiber intakes were consistently below recommendations, while total fat and saturated fat intakes were generally above recommendations and carbohydrate and polyunsaturated fat intakes were below to borderline low compared with recommendations. A mismatch between dietary practices and macronutrient recommendations in pregnant women is widespread and not well quantified. The implications of these practices are unknown until further research compares maternal diet with short-term and long-term maternal and offspring health outcomes.

Type of milk feeding affects hematological parameters and serum lipid profile in Japanese infants

BACKGROUND

Type and volume of infant feeding determines infant growth, hematological parameters, and serum lipids.

METHODS

Study subjects consisted of 103 infants who were born vaginally at term, with birthweight >2200 g. Milk feeding amount, type, and anthropometry were measured at 1 and 6 months. Hematological tests and serum lipid profile were assessed at 1 and 6 months. Thirty-four infants were breast-fed and 36 were formula-fed at 6 months.

RESULTS

Breast-fed infants demonstrated similar growth patterns compared with partially breast-fed or formula-fed infants, despite the lower milk intake. Infants with higher breast milk intake at 6 months, however, tended to have lower hemoglobin levels. In contrast, higher formula intake at 6 months was related to lower serum total cholesterol.

CONCLUSIONS

Japanese breast-fed infants were more likely to be anemic at 6 months, while formula-fed infants were likely to have low serum lipid levels. Iron-fortified infant foods may be useful to prevent anemia in breast-fed infants. Fat quality of infant formulas should be improved to enhance lipid status of formula-fed infants.

Determination of the minimal essential serum folate concentration for reduced risk of colorectal adenoma

BACKGROUND & AIMS

There are no data regarding basal folate levels in patients without colorectal adenoma. This study aimed to determine the minimum serum folate concentration that associates with reduced risk of colorectal adenoma.

METHODS

1510 consecutive patients underwent total colonoscopy for suspected colorectal lesions after barium enema examination. Prior to colonoscopy, history of alcohol consumption was noted and blood serum analyzed for folate and vitamin B12 levels. Polypoid lesions were evaluated histologically. We excluded patients with anemia, history of colonoscopy, overconsumption of alcohol, or malignancies. In all, 458/1510 patients (male/female; 258/200, 40-75 years) were determined eligible. Variables were compared between patients with adenoma and those without adenoma.

RESULTS

Serum folate concentration was the variable with the most significant statistical variation between males with adenoma (8.0 ng/ml) and males without adenoma (9.2) (p = 0.001). Serum folate concentrations in females with adenoma did not differ significantly from those in females without adenoma (10.7 versus 10.9). When subjects were stratified into groups according to serum folate, we found no significant difference in the prevalence of adenoma in patients with folate levels greater than 8.0 ng/ml.

CONCLUSION

Patients with serum folate concentrations above 8.0 ng/ml had the lowest risk of developing colorectal adenoma.

Nutritional adequacy of three dietary patterns defined by cluster analysis in 997 pregnant Japanese women: the Osaka Maternal and Child Health Study

OBJECTIVE

To examine the adequacy and inadequacy of dietary patterns in pregnant women for which information is absolutely lacking.

DESIGN

Diet was assessed by a validated, self-administered diet history questionnaire (DHQ). Dietary patterns were extracted from the intake of thirty-three food groups (g/4184 kJ (1000 kcal)), which were summarized from 147 foods assessed with the DHQ, by cluster analysis. Nutritional inadequacy for selected twenty nutrients in each dietary pattern was examined using the reference values given in the Dietary Reference Intakes (DRI) for Japanese as the temporal gold standard.

SETTING

Japan.

SUBJECTS

Nine hundred and ninety-seven pregnant Japanese women aged 18-43 years.

RESULTS

The three dietary patterns identified were labelled as 'meat and eggs' (n 423), 'wheat products' (n 371) and 'rice, fish and vegetables' (n 203). The 'rice, fish and vegetables' pattern characterized by high intake of rice, vegetables, potatoes, pulses, fruits, seaweed, fish and miso soup showed significantly the lowest prevalence of inadequate intake for fifteen nutrients and significantly the highest prevalence of inadequate sodium intake. In contrast, the 'wheat products' pattern characterized by high intake of bread, noodles, confectioneries and soft drinks showed the highest prevalence of inadequate intake for fourteen nutrients. The median number of nutrients not meeting the DRI as a marker of overall nutritional inadequacy was eight in the 'rice, fish and vegetables' pattern. It was significantly lower at ten in the 'meat and eggs' and eleven in the 'wheat products' patterns (P<0.001).

CONCLUSIONS

In pregnant Japanese women, the dietary pattern high in rice, fish, vegetables, fruit and some others showed a better profile of nutritional adequacy except for sodium.

Folic acid in the prevention of neural tube defects: awareness among laywomen and healthcare providers in Japan

It is known that neural tube defects are folic acid preventable congenital anomalies. We investigated to what extent this information was disseminated among laywomen and healthcare providers. Questionnaire studies were conducted twice, in 2002 and 2007, for four groups of laywomen and seven groups of healthcare providers in Japan regarding awareness, folic acid supplements and healthy diets. Awareness among laywomen was less than 20%, except for families who had experience with spina bifida in 2002, and 5 years later only pregnant women showed a significant increase in awareness. Awareness among healthcare providers varied from 12 to 76%, depending on their profession, and this proportion increased in five of the seven groups in 2007. The majority of laywomen obtained their information from mass media, while the majority of healthcare providers received information through media for professionals. Laywomen who used folate supplements and healthcare providers who recommended them were initially fewer than 25 and 37%, respectively. Five years later, however, pregnant women who used folic acid supplements increased from 9.1 to 43.1%. As awareness among non-pregnant laywomen and some healthcare providers is considerably low, information should be presented repeatedly to these groups. The difficulty in getting women to consume folic acid supplements is an argument for the government to require folic acid fortification of grains so that the prevention of neural tube defects can be maximized.

Dietary folate intake, use of folate supplements, lifestyle factors, and serum folate levels among pregnant women in Tokyo, Japan

AIM

The aim of this study was to determine the folate status of pregnant women and how it is affected by dietary folate, use of folate supplements, and lifestyle factors (smoking and drinking habits).

METHODS

This cross-sectional study involved 537 healthy, pregnant women attending an obstetric clinic in a Tokyo suburb. Morning blood samples were taken to determine serum folate levels. A brief, self-administered diet history questionnaire and another questionnaire were used to obtain information about food intake and demographic data. Logistic regression was used to identify factors associated with a normal serum folate level (> 6 ng/mL), taking women with a low serum folate level (< or = 6 ng/mL) as the reference group.

RESULTS

The median dietary folate intake was 207.2 microg/day; the median serum folate level was 3.9 ng/ml. A normal serum folate level was significantly associated with increased dietary folate intake (odds ratio = 1.003, P < 0.05), use of folate supplements (odds ratio = 8.152, P < 0.001), and more than four cups of green tea (odds ratio = 0.467, P < 0.05), but not with lifestyle factors in the adjusted analysis.

CONCLUSIONS

Most pregnant women (79.3%) in the present study had a low serum folate level, reflecting a low dietary intake of folate and a low proportion of women taking folate supplements. Supplement use had a much stronger association with a normal serum folate level than dietary folate intake. Since this study was not population-based, further studies are needed to confirm the results.

Relationship between dietary folate intakes, maternal plasma total homocysteine and B-vitamins during pregnancy and fetal growth in Japan

BACKGROUND

Adequate folate status in pregnancy is important for satisfactory pregnancy outcome.

AIM OF THE STUDY

The objective of the present study was to evaluate folate status in healthy pregnant women by assessing dietary folate intakes and measuring changes in folate-related biomarkers including plasma tHcy, serum vitamin B(12) (B(12)), and serum and RBC folate concentrations in each trimester and to examine their relation to fetal growth.

METHODS

From 94 pregnant women, 3-day-dietary records were obtained and blood was collected for plasma total homocysteine (tHcy), serum B(12), and serum and red-blood cell (RBC) folate measurements. Infant anthropometric measurements were made immediately after birth.

RESULTS

Average folate intake was less than 300 microg/day with a mean energy intake of about 1800 kcal. Mean serum and RBC folate concentrations declined significantly during gestation (p < 0.05). Mean serum B(12) also significantly decreased (p < 0.01), whereas plasma tHcy increased from 5.1 in the first trimester to 5.9 micromol/l in the third trimester (p < 0.01). Multiple regression analyses, after controlling for maternal age, parity and pre-pregnancy body-mass index indicated that a 1.0 micromol/l increase in plasma tHcy in the third trimester corresponded to a 151 g decrease in birth weight (p < 0.01). Neither B(12) nor folate concentrations in all three trimesters showed any significant associations with birthweight. Plasma pyridoxal-5'-phosphate concentrations were markedly low, and were consistent with low intake of vitamin B(6) in our population.

CONCLUSION

Our data suggest that higher plasma tHcy in the third trimester is a predictor of lower birth weight. In general, the dietary intake of B-vitamins and energy may be inadequate in our population, suggesting intervention is necessary.