Mandatory folic acid fortification may be unnecessary

Persistently present levels of unmetabolized folic acid found in the population indicate that introducing mandatory food fortification may result in an ‘overdosing’ effect. A study of blood donors, new mothers and babies, published in the open access journal BMC Public Health, has found that most already get enough folic acid from voluntarily fortified foods.

Mary Rose Sweeney, from Dublin City University, Ireland, led a team of researchers who studied 50 blood samples from the Irish Blood Transfusion Service and from 20 mothers and 20 infants’ umbilical–cords, from Coombe Women’s and Infants’ University Hospital, also in Dublin. She said, “A recent study has suggested excessive folic acid consumption may increase the risk of prostate cancer and more severe adenorectal carcinoma recurrence. We set out to explore how much unmetabolized folic acid is present in Irish people exposed to the current range of ‘voluntarily’ fortified foodstuffs, and to predict the increase in levels should a policy of mandatory fortification be introduced”.

Folic acid and other micronutrients have been added on a voluntary basis to breakfast cereal, bread and other products in the Republic of Ireland for over 15 years, to remedy perceived inadequate intake. The Food Safety Authority in Ireland is currently discussing whether to make such fortification mandatory. In this study, Sweeney and her colleagues found that circulatory unmetabolized folic acid was present in the majority of their sample. They write, “This implies constant exposure of both normal cells, and potential tumour cells, to this pro-vitamin amongst Irish consumers. In terms of the increase that might arise if mandatory fortification goes ahead, we predict it to be in the region of 12%”.

The consequences of increased consumption of folic acid are still unknown, but, according to the researchers, “This should continue to be of concern for those with responsibility for drafting legislation in this area”.