Revised D-A-CH intake recommendations for folate: how much is needed?

The D-A-CH reference value (D-A-CH arises from the initial letters of the common country identification for the countries Germany (D), Austria (A) and Switzerland (CH)) for folate equivalents had been set at 400 μg/d for adults in the year 2000. By that time, the prevention of cardiovascular diseases through reduction of homocysteine was considered an important target of the reference value. Since that time a number of research papers revealed that in spite of an inverse association between folate-rich diet and chronic diseases, a preventive effect of folic acid intake on cardiovascular events was not supported by randomized controlled trials, and the reduction of plasma homocysteine levels to around 10–12 μmol/l did not reduce the risk for thromboembolic and cardiovascular diseases in persons already affected by these diseases. These results together with the observation that folate intakes below 400 μg/d result in a sufficient folate status justified a review of the current literature and—consequently—a reduction of the reference value to 300 μg/d for adults. This reference value is expressed as dietary folate equivalents that take into account the difference in bioavailability between folic acid and all types of folates in food. The recommendation to take a daily supplement of 400 μg of synthetic folic acid for women who intend to get pregnant and until the end of the first trimester of pregnancy is maintained.