Dr Mary Flynn from the Food Safety Authority of Ireland, the key authority on nutrition for the Irish government, has repeatedly upheld that the maximum level of supplements required by the Irish people is the Recommended Daily Allowance.

Three papers emerged last week in the Archives of Internal Medicine that disproved this. A rash of papers on vitamin D over the last 5 years have disproven this. And now a study from Ireland’s own Trinity College has disproven this.

Dr Flynn’s ‘RDA-should-be-the-maximum-permitted-level’ stand is out of step with virtually every health authority worldwide, including the World Health Organization, the National Institutes of Health in the USA and the European Commission itself. Even the European Food Supplements Directive (Directive 2002/46/EC) itself makes plain (in Article 5) that risk assessment and risk management will be the mechanism by which maximum levels of vitamins and minerals will be harmonised across Europe.

One of Dr Flynn’s stated reasons against higher dose supplementation is Ireland’s very high 55% unplanned and undiagnosed pregnancy rate. Dr Flynn has argued that higher level supplementation could expose unborn foetuses to risk. Well, now we have more evidence that inadequate vitamin levels expose the unborn foetus to risk!

Irish study

Dr Flynn is going to have a hard time ignoring this latest study published in the journal Paediatrics by a team at Trinity College Dublin. The study is one of at least two to show definitively that folic acid is not the only vitamin that is needed to reduce the risk of neural tube defects, such as spina bifida. Those with low circulating levels of the closely related vitamin B12 are also significantly at risk. The Irish study, led by Dr Anne Molloy, suggests that serum levels of B12 greater than 300 ng/L are required, and we know for many people this requires taking substantially over the 1 mcg EU RDA.

Canadian study

Another very recently published study that also points to the same need for higher levels of B12 in conjunction with folate was undertaken by Miles Thompson and colleagues at the University of Toronto. This again shows that B12 supplementation, along with the normally recommended 400 mcg/day supplementation of folic acid, will significantly reduce the risk of neural tube defects.

To conclude

Just as more and more research emerges about the importance of vitamins and minerals in the prevention of disease, isn’t it peculiar that we are facing so much regulatory pressure to restrict these nutrients, that are paid for out of the private purse and so cheap, with almost no known side effects at recommended levels of use?

Although such studies may encourage governments to push for further fortification programmes, where B12 is added in conjunction with folic acid, high dose supplementation must be kept available for those who choose to avoid fortified products (often because they are more processed), do not consume wheat (e.g., because they are gluten intolerant or have a greater physiological requirement.

Is Dr Flynn from Ireland’s Food Safety Authority listening?


The abstracts of both studies can be found below:

Abstract 1

Molloy AM, Kirke PN, Troendle JF, Burke H, Sutton M, Brody LC, Scott JM, Mills JL. Maternal vitamin B12 status and risk of neural tube defects in a population with high neural tube defect prevalence and no folic Acid fortification. Pediatrics 2009; 123(3): 917-23.

Trinity College Dublin, School of Medicine, Dublin 2, Ireland. 

OBJECTIVE. Folic acid fortification has reduced neural tube defect prevalence by 50% to 70%. It is unlikely that fortification levels will be increased to reduce neural tube defect prevalence further. Therefore, it is important to identify other modifiable risk factors. Vitamin B(12) is metabolically related to folate; moreover, previous studies have found low B(12) status in mothers of children affected by neural tube defect. Our objective was to quantify the effect of low B(12) status on neural tube defect risk in a high-prevalence, unfortified population. METHODS. We assessed pregnancy vitamin B(12) status concentrations in blood samples taken at an average of 15 weeks' gestation from 3 independent nested case-control groups of Irish women within population-based cohorts, at a time when vitamin supplementation or food fortification was rare. Group 1 blood samples were from 95 women during a neural tube defect-affected pregnancy and 265 control subjects. Group 2 included blood samples from 107 women who had a previous neural tube defect birth but whose current pregnancy was not affected and 414 control subjects. Group 3 samples were from 76 women during an affected pregnancy and 222 control subjects. RESULTS. Mothers of children affected by neural tube defect had significantly lower B(12) status. In all 3 groups those in the lowest B(12) quartiles, compared with the highest, had between two and threefold higher adjusted odds ratios for being the mother of a child affected by neural tube defect. Pregnancy blood B(12) concentrations of <250 ng/L were associated with the highest risks. CONCLUSIONS. Deficient or inadequate maternal vitamin B(12) status is associated with a significantly increased risk for neural tube defects. We suggest that women have vitamin B(12) levels of >300 ng/L (221 pmol/L) before becoming pregnant. Improving B(12) status beyond this level may afford a further reduction in risk, but this is uncertain.

Abstract 2

Thompson MD, Cole DE, Ray JG. Vitamin B-12 and neural tube defects: the Canadian experience. Am J Clin Nutr. 2009; 89(2): 697S-701S.

Department of Laboratory Medicine and Pathobiology, Banting Institute, University of Toronto, Toronto, ON, Canada.

Although early epidemiologic studies showed a protective effect of adequate maternal folic acid (FA) status against neural tube defects (NTDs), the role of adequate vitamin B-12 nutrition in the putative reduction of NTD frequency has remained uncertain. Evaluating vitamin B-12 status was complicated by the need to control for altered FA status after fortification in Canada. More recent studies have made use of better biomarkers of vitamin B-12 status, including methylmalonic acid and holotranscobalamin (holoTC). HoloTC provides a useful measure of vitamin B-12 status because it represents the bioavailable fraction of circulating vitamin B-12. By assessing bioavailable vitamin B-12 status in a large Canadian cohort accrued before and after FA fortification, we found a 3-fold increase in the risk of NTDs in mothers who had vitamin B-12 status in the lower quartile, regardless of FA fortification. Our work suggests that vitamin B-12 fortification, analogous to the FA fortification program, may reduce NTDs more than FA fortification alone. A multicenter randomized controlled trial comparing periconceptional vitamin B-12 in combination with FA against FA alone is warranted.