Folate intake in Europe: recommended, actual and desired intake

Abstract

Objectives: To evaluate possible inconsistencies between recommended, actual and desired folate intake in European adult populations. Design: Review of dietary recommendations, of food consumption surveys, and of intervention and observational studies relating folate intake to the risk of neural tube defects and plasma homocysteine levels. Results: In Europe, mean dietary folate intake in adults is 291 μg/d (range 197–326) for men and 247 μg/d (range 168–320) for women. The recommended intakes vary between 200–300 μg/d (men) and 170–300 μg/d (women). However, women with a previous pregnancy affected by a neural tube defect (NTD), are recommended to take 4000 μg/d of supplemental folic acid when planning a subsequent pregnancy. For those without a history of NTD, the use of 400 μg/d of supplemental folic acid is the best option to prevent the occurrence of NTDs. A daily dose of 650 μg supplemental folic acid normalises elevated plasma homocysteine levels, which is a risk factor for cardiovascular diseases. A dietary folate intake of at least 350 μg/d is desired to prevent an increase in plasma homocysteine levels of the adult population in general. Conclusions: Mean dietary folate intake in Europe is in line with recommendations, but the desired dietary intake of <350 µg/d is only reached by a small part of studied European populations. It is considered unethical to investigate whether supplements with a dose lower than 400 μg/d of folic acid are also protective against NTDs. However, research to establish the lowest effective dose of dietary folate/supplemental folic acid to optimise homocysteine levels and research on the bioavailability of folate is required. This will enable the choice of a strategy to achieve desired folate intakes in the general population. In the meantime, consumption of plant foods like vegetables, fruits, and cereals should be stimulated to reach the desired level of 350 μg of dietary folate per day.