NEW DATA ABOUT FOLIC ACID SUPPLEMENTATION

Folic acid supplementation during pregnancy and the prevention of neural tube defects is undoubtedly one of the great success stories of the past two decades. However, as we have learned on numerous occasions, there can be unintended adverse consequences of nutritional and drug interventions. Over the past few years, there has been increasing interest in the role of methylation and its potential impact on gene expression and disease phenotypes. In a report from Norway, a country in which food is not fortified with folic acid but is recommended during pregnancy, Haberg and colleagues describe the impact folic supplement during pregnancy has on early childhood respiratory health. They cite both invitro and animal data as the basis for their hypothesis that supplementation could increase the risk of lower respiratory tract infection because of the impact of folic acid on methylation and subsequent T-cell function. Over 30 000 women were included in the study (ultimately 100 000 pregnant women will be enrolled), with nutritional information collected at the 17^th and 30^th week of pregnancy, and information about their offspring at 6 and 18 months. They quantified folic acid supplementation throughout pregnancy. …