
Folic Acid
Vitamin B9, is often also called folic acid. It is a collective term for various folic acids. As another B vitamin, vitamin B9 is one of the critical nutrients in an omnivore diet. To ensure sufficient intake, certain food groups and their storage and preparation must be taken into account. In this post you will learn the most important facts about folic acid and what you can do to get enough of it.
Functions
Vitamin B9, also called folic acid, is a cofactor in the production of amino acids. Therefore, it plays an essential role in the production of our DNA, which consists of amino acids. Especially before and during pregnancy, a sufficient intake of folic acid is necessary to avoid malformations. Tetrahydrofolic acid has the ability to absorb and transfer compounds with one carbon atom. As a result, folic acid, together with vitamins B6 & B12, plays an important role in the breakdown of homocysteine.
Occurrence
The name folic acid comes from the Latin folium, which means leaf. It is therefore not surprising that folic acid is found in green leafy vegetables.
- Green leafy vegetables
- green beans
- Tomatoes
- Yeast
- Nuts
- cereal sprouts
- Legumes
- Whole grains
In Switzerland, processed products (especially baked goods) that contain enough folic acid are labelled by the Folic Acid Foundation.
Metabolism
In addition, folic acid is
- light-sensitive
- heat-labile
- susceptible to oxidation
It is therefore advisable to store the products protected from light and, if possible, to eat them raw and fresh. This is of course not possible with pulses. Preparation losses average 35% and bioavailability is about 40-60%. In the case of supplements, the absorption is up to 100 %, which explains why the upper intake limit is set lower.
Recommended intake
The recommendation is 300 µg/day of folate equivalent. The tolerable upper intake level is 1000 µg/day for dietary folate and 500 µg/day for synthetic folate (supplements). Pregnant and nursing women are recommended to take 550 µg/day and breastfeeding women 450 µg/day of folate equivalents. This is necessary to avoid malformations in the foetus.
Deficiency
Causes of folic acid deficiency can be absorption disorders, alcoholism, medication as well as loss during preparation. Symptoms may include the following:
- Increased homocysteine levels → higher risk of vascular disease.
- Impaired purine and DNA synthesis → Impaired cell division in the bone marrow
- Anaemia
- Reduced antibody formation
- Epithelial changes in the gastrointestinal tract
- Sleep disorders, forgetfulness and depression
A vitamin B12 deficiency can be accompanied by typical folic acid deficiency symptoms. A B12 deficiency can be masked by taking 5 mg or more of synthetic folic acid.
A deficiency during conception and pregnancy can lead to abortions, malformations, developmental disorders and neural tube defects of the foetus. In this context, I would like to draw your attention to the Folic Acid Foundation.
Supply
The average is clearly below the recommendation. 79 % of men and 86 % of women are below the recommendations.

