Lately, folic acid deficiency is gaining a predominant role in the pathogen
esis of congenital malformations and cardiovascular diseases in adults. The
planning of individual and population preventive strategies for these dise
ases must consider this deficiency. This paper reviews the anatomical, bioc
hemical and molecular bases of neural tube defects and cardiovascular disea
ses in adults. In these two frequent diseases, folic acid supplementation h
as shown a clear cut protective effect.