Intake of dietary folate and folic acid in Germany based on different scenarios for food fortification with folic acid

Biological, dietetic and pharmacological properties of vitamin B9

Humans must obtain vitamin B9 (folate) from plant-based diet. The sources as well as the effect of food processing are discussed in detail. Industrial production, fortification and biofortification, kinetics, and physiological role in humans are described. As folate deficiency leads to several pathological states, current opinions toward prevention through fortification are discussed. Claimed risks of increased folate intake are mentioned as well as analytical ways for measurement of folate.

Impact of folic acid supplementation on the epigenetic profile in healthy unfortified individuals - a randomized intervention trial

Folate is an essential mediator in one-carbon metabolism, which provides methyl groups for DNA synthesis and methylation. The availability of active methyl groups can be influenced by the uptake of folic acid. We conducted a randomized intervention trial to test the influence of folic acid supplementation on DNA methylation in an unfortified population in Germany. A total of 16 healthy male volunteers (age range 23-61 y) were randomized to receive either 400 μg (n = 9) or 800 μg (n = 7) folic acid supplements daily for 8 weeks. Infinium Human Methylation 450K BeadChip Microarrays were used to assay site-specific DNA methylation across the genome. Microarray analyses were conducted on PBL DNA. We estimated several epigenetic clocks and mean DNA methylation across all autosomal probes on the array. AgeAccel was estimated as the residual variation in each metric. In virtually all participants, both serum and red blood cell (RBC) folate increased successively throughout the trial period. Participants with a larger increase in RBC folate had a larger increase in DNAmAge AgeAccel (Spearman Rho: 0.56, p-value = 0.03). No notable changes in the methylome resulting from the folic acid supplementation emerged. In this population with adequate folate levels derived from diet, an increase in RBC folate had a modest impact on the epigenetic clock predicting chronologic age.

Scientific opinion on the tolerable upper intake level for folate

Following a request from the European Commission (EC), the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the revision of the tolerable upper intake level (UL) for folic acid/folate. Systematic reviews of the literature were conducted to assess evidence on priority adverse health effects of excess intake of folate (including folic acid and the other authorised forms, (6S)-5-methyltetrahydrofolic acid glucosamine and l-5-methyltetrahydrofolic acid calcium salts), namely risk of cobalamin-dependent neuropathy, cognitive decline among people with low cobalamin status, and colorectal cancer and prostate cancer. The evidence is insufficient to conclude on a positive and causal relationship between the dietary intake of folate and impaired cognitive function, risk of colorectal and prostate cancer. The risk of progression of neurological symptoms in cobalamin-deficient patients is considered as the critical effect to establish an UL for folic acid. No new evidence has been published that could improve the characterisation of the dose-response between folic acid intake and resolution of megaloblastic anaemia in cobalamin-deficient individuals. The ULs for folic acid previously established by the Scientific Committee on Food are retained for all population groups, i.e. 1000 μg/day for adults, including pregnant and lactating women, 200 μg/day for children aged 1-3 years, 300 μg/day for 4-6 years, 400 μg/day for 7-10 years, 600 μg/day for 11-14 years and 800 μg/day for 15-17 years. A UL of 200 μg/day is established for infants aged 4-11 months. The ULs apply to the combined intake of folic acid, (6S)-5-methyltetrahydrofolic acid glucosamine and l-5-methyltetrahydrofolic acid calcium salts, under their authorised conditions of use. It is unlikely that the ULs for supplemental folate are exceeded in European populations, except for regular users of food supplements containing high doses of folic acid/5-methyl-tetrahydrofolic acid salts.

Hyperhomocysteinemia: Metabolic Role and Animal Studies with a Focus on Cognitive Performance and Decline-A Review

Disturbances in the one-carbon metabolism are often indicated by altered levels of the endogenous amino acid homocysteine (HCys), which is additionally discussed to causally contribute to diverse pathologies. In the first part of the present review, we profoundly and critically discuss the metabolic role and pathomechanisms of HCys, as well as its potential impact on different human disorders. The use of adequate animal models can aid in unravelling the complex pathological processes underlying the role of hyperhomocysteinemia (HHCys). Therefore, in the second part, we systematically searched PubMed/Medline for animal studies regarding HHCys and focused on the potential impact on cognitive performance and decline. The majority of reviewed studies reported a significant effect of HHCys on the investigated behavioral outcomes. Despite of persistent controversial discussions about equivocal findings, especially in clinical studies, the present evaluation of preclinical evidence indicates a causal link between HHCys and cognition-related- especially dementia-like disorders, and points out the further urge for large-scale, well-designed clinical studies in order to elucidate the normalization of HCys levels as a potential preventative or therapeutic approach in human pathologies.

[Women with epilepsy before and during pregnancy: a case series of outpatient counseling in a tertiary epilepsy center]

BACKGROUND

Data of large pregnancy registries have improved the recommendations for women with epilepsy before pregnancy. Monotherapy containing antiepileptic drugs with a low malformation rate (lamotrigine or levetiracetam) is recommended as well as preconceptional folic acid supplementation, while valproic acid should be avoided. The practicability of these recommendations remains controversial.

METHODS

Retrospective case series of 160 women with epilepsy over a period of 5 years who were advised in our outpatient department before and during pregnancy.

RESULTS

Only 18.9% of women presented with valproic acid. Even without valproic acid, complications or emergency admissions rarely occurred under specialist supervision. In our case series, lamotrigine proved to be less effective and less controllable than other drugs during pregnancy. Levetiracetam also has a low malformation rate, but showed a better effect on seizure outcome during pregnancy than lamotrigine. Only 12% of women who wanted to have children took folic acid.

CONCLUSION

This case series comes from a tertiary center; the referred women were mainly accompanied by neurologists with special expertise in epileptology. In this group valproate could be avoided in most cases. Lamotrigine is probably less effective due to the drop in blood levels during pregnancy. Levetiracetam seems to be a good alternative, working well against focal and generalized seizures. Folic acid may be taken later than recommended.

Micronutrient dietary intakes and their food sources in adults: the Hellenic National Nutrition and Health Survey (HNNHS)

BACKGROUND

The present study aimed to assess micronutrient intake among Greek adults and to identify the main food sources that contribute to it.

METHODS

Food consumption data from 2389 participants in the Hellenic National Nutrition and Health Survey (HNNHS), collected with 24-h recalls, was used to calculate micronutrient intakes. Usual nutrient intake was estimated according to the National Cancer Institute method. Nutrient adequacy was estimated using the estimated average requirement (EAR) cut-point method, when available, or adequate intake otherwise. The probability approach was used to determine iron intake adequacy in females of reproductive age. Food group contribution for each nutrient assessed was derived to identify their main food sources.

RESULTS

Almost all individuals had vitamin D intake below EAR, whereas vitamins A, E, K and C, as well as potassium intake, were also insufficient in a considerable percentage of the population (>70% in most age groups). Calcium intake was substantially below the EAR for females aged >50 years and males >70 years; the same for magnesium in males >70 years. Furthermore, 50% of females, including those of reproductive age, had intake of folate below EAR. More than 50% of the population (to 79%) exceeded the upper tolerable limit for sodium (2300 mg day^-1 ). Food contribution analysis revealed that most vitamins were derived from low-quality foods (i.e. fast-food).

CONCLUSIONS

A significant proportion of adults residing in Greece have low nutrient intake and poor food selections. These results provide guidance to public health policy makers for developing strategies to improve the dietary quality in Greece.

Micronutrient intakes and their food sources among Greek children and adolescents

OBJECTIVE

To assess the usual dietary intake of twenty micronutrients and to identify their food sources in a representative sample of Greek children and adolescents.

DESIGN

Cross-sectional data from the Hellenic National Nutrition and Health Survey (HNNHS). Vitamin and mineral intakes were estimated from two 24 h dietary recalls by sex and age groups. Estimates were calculated using the National Research Council method and the statistical software package Stata13 to account for within- and between-person variations. The prevalence of nutrients' inadequacy among sample was estimated using the estimated average requirement (EAR) cut-point method. The contribution of food groups to nutrient intake was estimated to identify micronutrients food sources.

SETTING

Greece.

PARTICIPANTS

Children and adolescents aged 1-19 years (n 577) who provided sufficient and plausible 24-h recalls.

RESULTS

A substantial percentage of children and adolescents had insufficient intakes of numerous micronutrients. Usual intake of vitamins D, K and potassium was inadequate in practically all individuals. Vitamin A, folate, Ca and Mg were also insufficient to a considerable percentage, especially in girls aged 14-18 years. Pantothenic acid was highlighted as nutrient of interest since only one out of ten boys 9-13 years and girls 14-19 years had intake above the EAR. Data demonstrated that food groups highly ranked in energy contribution were not necessarily important sources of micronutrients.

CONCLUSIONS

Results suggest that micronutrient density of Greek children and adolescents' diet should be improved. These findings might be used by public health policy-makers to help young people optimise their food choices in Greece.

Overfed but undernourished: recognizing nutritional inadequacies/deficiencies in patients with overweight or obesity

Overweight and obesity are highly prevalent throughout the world and can adversely affect the nutritional status of individuals. Studies have shown that many people with obesity have inadequate intake of iron, calcium, magnesium, zinc, copper, folate and vitamins A and B₁₂, likely as a result of poor diet quality. Nutritional inadequacies or deficiencies may also occur due to altered pharmacokinetics in the individual with obesity and due to interactions in those with overweight or obesity with various pharmaceuticals. However, it has been demonstrated that the adult population in the United States as a whole is deficient in certain micronutrients as a result of the availability and overconsumption of high-calorie, low-nutrient processed foods. Poor nutrition may contribute to the development of certain chronic conditions, such as type 2 diabetes, which is already more prevalent in those with obesity. Clinicians need to be aware of these gaps, particularly in those individuals with obesity who are undergoing bariatric surgery or taking pharmaceutical products long term to facilitate weight loss. Patients with overweight or obesity likely struggle to achieve a balanced diet and may benefit from consultation with a dietitian. Along with providing recommendations for healthy eating and exercise, supplementation with specific micronutrients or multivitamins should be considered for individuals at the highest risk for or with established deficiencies. Further research is needed to understand the factors underlying nutritional inadequacies in individuals with overweight or obesity, as well as the outcomes of treatment strategies employed to address them.

Dietary Micronutrient and Mineral Intake in the Mediterranean Healthy Eating, Ageing, and Lifestyle (MEAL) Study

BACKGROUND

Dietary vitamins and minerals are essential compounds for the proper functioning of metabolic enzymes, regulation of gene transcription, and powering the body’s defense against oxidative stress. The aim of the present study was to investigate micronutrient consumption separately by age and sex, major dietary sources, and percentage of individuals meeting the recommended requirements according to Italian (Livelli di Assunzione di Riferimento di Nutrienti (LARN)) and European (European Food Safety Agency (EFSA)) agencies.

METHODS

Data were obtained from the Mediterranean Healthy Eating, Ageing, and Lifestyle (MEAL) study, which included a sample of 1838 individuals randomly collected in the city of Catania, southern Italy. A validated food frequency questionnaire was used to collect information on diet.

RESULTS

Intake of vitamin A, vitamin C, and vitamin B group (except vitamin B9) was in line with other reports and was adequate according to the guidelines, while the percentage of individuals meeting the guidelines for vitamin D, vitamin E, and vitamin B9 was about 3%, 10%, and 40%, respectively. Among minerals, intake of iron, magnesium, and selenium was adequate for most of the sample, while the percentage of individuals meeting the recommendations for calcium, sodium, and potassium intake was about 20%, 8%, and 35%, respectively.

CONCLUSIONS

An important percentage of the population would benefit from campaigns raising awareness of micronutrient deficiency or excessive consumption potentially affecting their health.

High-dose maternal folic acid supplementation before conception impairs reversal learning in offspring mice

Maternal folic acid (FA) supplementation prior to and during gestation is recommended for the prevention of neural tube closure defects in the developing embryo. Prior studies, however, suggested that excessive FA supplementation during gestation can be associated with toxic effects on the developing organism. Here, we address whether maternal dietary folic acid supplementation at 40 mg/kg chow (FD), restricted to a period prior to conception, affects neurobehavioural development in the offspring generation. Detailed behavioural analyses showed reversal learning impairments in the Morris water maze in offspring derived from dams exposed to FD prior to conceiving. Furthermore, offspring of FD dams showed minor and transient gene expression differences relative to controls. Our data suggest that temporary exposure of female germ cells to FD is sufficient to cause impaired cognitive flexibility in the subsequent generation.

Vitamin D intake of Dutch infants from the combination of (fortified) foods, infant formula, and dietary supplements

Purpose

Due to changes in the Dutch fortification policy for vitamin D and the vitamin D supplementation advice for infants (10-μg/d for 0–4 year olds), a partially virtual scenario study was conducted to evaluate the risk of excessive vitamin D intake assigning all infants to a 100 % adherence to the supplementation advice and considering the current fortification practice.

Methods

Food consumption data from the Nutrition Intake Study (2002; N = 941, 7–19 months) were combined with Dutch food composition data from 2011 to estimate vitamin D intake from (fortified) foods. For infants 0–6 months of age, the consumption volume infant formula was estimated from energy requirement and body weight. All subjects were assigned to take a daily 10 µg vitamin D supplement, according the Dutch supplementation advice for infants. Habitual vitamin D intake was estimated using the Statistical Program to Assess Dietary Exposure and compared with the tolerable upper intake levels (ULs) set by the European Food Safety Authority.

Results

The median habitual total vitamin D intake was 16–22 µg/day for infants aged 0–6 months (increasing with age) and 13–21 µg/day for infants aged 7–19 months (decreasing with age). About 4–12 % of infants aged 7–11 months exceeded the UL. At the 99th percentile, the intake was 2–4 µg above the UL, depending on age. Infants aged 0–6 and 12–19 months did not exceed the UL.

Conclusions

In case of combined intake from infant formula, (fortified) foods, and supplements, vitamin D intakes above the UL are possible among some infants during a limited time period.