She discovered that the body has a limited ability to absorb the most common form of folic acid (vitamin B11), thus compounding the fact that the average Dutch person consumes too little of this vitamin anyway. Folic acid is not just something that pregnant women should take to reduce the chance of a child with spina bifida. There are now indications that folic acid can also reduce the risk of cardiovascular diseases.
The researchers state that the amount of folic acid in the blood could be increased by means of nutritional advice or new products that contain either more folic acid or a more easily absorbable form of folic acid. Up until now, Dutch law has forbidden the enrichment of products with folic acid. However, plant breeding might provide a solution to this problem.
In cooperation with the National Institute of Public Health and the Environment (RIVM), the researchers analysed the food intake of 2435 people aged 20 to 65 years. Although the recommended daily intake of folic acid has recently been increased to 300 micrograms per day, the average intake was found to be about 250 micrograms per day. Two-thirds of this amount was in the polyglutamate form.
Folic acid occurs in two different forms: bound to a polyglutamate or to a monoglutamate. The small intestine first of all has to convert the polyglutamate form of folic acid into the monoglutamate form, before the body can absorb the vitamin. The researchers wanted to establish whether this extra conversion step meant that the polyglutamate form was less well absorbed than the monoglutamate form.