An adequate intake of folate during pregnancy, lactation, and infancy is essential for maternal and child health and normal growth. Higher folate requirements during pregnancy and lactation are difficult to meet by increased intake of folate-rich food products only. Supplementation with folic acid is recommended not only to meet the higher requirements but also to prevent adverse pregnancy outcomes such as neural tube defects (NTDs). In countries that have implemented food fortification with folic acid, the folate intake has raised but does not yet meet the recommended amount for NTD risk reduction. Women’s awareness of the need to supplement with folic acid prior to conception shall be raised in all countries. It is under debate whether a high folic acid intake might have metabolic and functional effects in utero and for the infant. Research is needed to investigate potential alternative folate forms for food fortification programs and to test their efficacy in risk reduction of adverse pregnancy outcomes. Breast-fed infants most likely receive sufficient folate. While the folate level of human milk is simulated in infant formula, data are lacking on the bioavailability and effect of folic acid in infants and on whether a tolerable upper intake level should be defined.

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