Vitamin B9 (folic acid)

• The recommended intake is 300 µg per day, for pregnant women 400-600 µg per day.
• The folate store in the liver is only sufficient for three to four weeks if the intake is insufficient.
• Folic acid and folate are derived from the Latin word "folium" (leaf).
• Supplementation even before pregnancy is extremely important for the prevention of neuronal tube defects (open back)

In foods, folic acid is present as folate. Chemically, the two forms differ in the number of so-called glutamate residues on the basic structure. Folic acid, as contained in supplements, is a monoglutamate - that is, it contains only one glutamate. Folates, on the other hand, exist as polyglutamates and can contain up to 8 glutamate residues. These are broken down in the small intestine, as the body can only absorb monoglutamates. Therefore, folic acid from supplements is absorbed in almost 100%. The absorption capacity of folates from food is only about half as great.

If the glutamates have been cut off in the intestine, the folic acid is absorbed into the intestinal cells. There it is converted into 5-methyl-tetrahydrofolate (5-methyl-THF) and then transported via the blood to the liver. Since the conversion in the intestinal cells is not a major challenge for the body, there is little advantage to taking folic acid (5-methyl-THF) that has already been activated. In addition, this form is more unstable and poorly studied than conventional folic acid.

Folate is very sensitive to heat, so it makes sense to use gentle methods when preparing foods. Up to 50% of the folate content can be lost during cooking.