Folic acid: a public-health challenge.

Despite worldwide public-health campaigns recommending periconceptional daily supplementation of synthetic folic acid to reduce the risk of neural tube defects, many women are not following these recommendations. At the same time, in most European countries no decline in defects has been recorded in recent years. Vulnerable groups are those with a low standard of education, young people, and women with unplanned pregnancies. Furthermore, in most countries without mandatory fortification, the general population is not consuming the recommended 0.4 mg of food folate per day. Voluntary fortification improves the situation, but does not reach all parts of the population. In the USA, Canada, and Chile, mandatory fortification of flour substantially improved folate and homocysteine status, and neural tube defects rates fell by between 31% and 78%. Nevertheless, many countries do not choose mandatory folic acid fortification, in part because expected additional health benefits are not yet scientifically proven in clinical trials, in part because of feared health risks, and because of the issue of freedom of choice. Thus, additional creative public-health approaches need to be developed to prevent neural tube defects and improve the folate status of the general population.