- Folic acid is a water-soluble vitamin and cannot be stored in the body. It must therefore be ingested via the daily diet.
- In Germany, the intake of folic acid (and its derivatives) is below the recommended daily levels, for both men and women and in all age groups.
- In Germany, only ca. 5% of women ages 18-49 meet the higher reference value for erythrocyte folate concentration levels recommended by the WHO for the prevention of neural tube defects.
- Folic acid is therefore a critical nutrient and requires special attention when it comes to nutrition and intake.
- In the US and Canada, the folic acid supply was also insufficient among the general population. There, grain products such as flour, pasta, rice, or oatmeal are often enriched with folic acid (since 1998). Since then, the folic acid status of the US and Canadian populations has largely been good. However, about 20% of young women of childbearing age still do not get enough folate.
- In Germany, enrichment is viewed more critically.
- The compounds that occur naturally in food are called folates, in contrast to synthetically produced folic acid.
- Folate and vitamin B12 metabolism are closely related.
Why Do We Need Folic Acid?
- Cell regeneration and cell division
- New formation of red blood cells (hematopoiesis), in close connection with iron, vitamin B12, and copper metabolism
- Homocysteine regulation
- DNA structure
- Proper closure of the neural tube in the third week of pregnancy
Possible Causes of Deficiency
- Diet is low in folic acid
- Loss of the vitamin in food preparation and storage
Increased intake requirements:
- Iron deficiency
- Chronic inflammatory bowel disease
- Celiac disease
Interaction with medication:
e.g., ASS, antacids, antibiotics, antiepileptics, diuretics, metformin, NSAID, oral contraceptives, methotrexate
Symptoms of Deficiency
- General: loss of appetite, pale skin, rapid fatigue, depression, weakness, changes in the oral mucosa, forgetfulness
- Blood: disorder of new blood formation, symptoms caused by anemia such as tiredness, shortness of breath, cardiac arrhythmia
- Immune system: immune system weakness
- Nervous system: increased risk of dementia, polyneuropathy
- Mucous membranes: inflammation of the tongue, oral mucosa or gums, mucosal atrophy
- Pregnancy: embryo malformation (e.g., neural tube defect), miscarriage, or premature birth
Recommended intake for adults:
- according to D-A-CH: 300 µg/day
- USA Food and Nutrition Board (FNB): 400 µg/day
- According to D-A-CH: 550 µg/day
- USA Food and Nutrition Board (FNB): 600 µg/day
- according to D-A-CH: 450 µg/day
- USA Food and Nutrition Board (FNB): 500 µg/day
Adolescents and children, depending on age, see
Important: Due to their rapid growth, children need additional folic acid. Adequate intake is particularly critical.
The Best Plant Sources (per 100 g)
Leafy greens and other vegetables, as well as grains and legumes, are particularly rich in folic acid. But be careful: folic acid is very sensitive to light and heat.
- Dry yeast – 900 µg
- Azuki beans – 622 µg
- Wheat germ – 350 µg
- Chickpeas, dried – 340 µg
- Soy flour, defatted – 300 µg
- Soybeans, dried – 250 µg
- Peanuts – 240 µg
- Sunflower seeds – 230 µg
- Wheat bran – 200 µg
- Peas, dried – 200 µg
- Green beans, dried – 190 µg
- Bean sprouts, raw – 160 µg
- Steamed spinach – 150 µg
- Lentils, dried – 150 µg
- Swiss chard – 148 µg
- Broccoli, raw – 148 µg
- Walnuts – 140 µg
- Endive, raw – 120 µg
- Kidney beans – 110 µg
- Arugula – 97 µg
- Savoy cabbage, raw – 90 µg
- Flax seeds – 87 µg
- Raw millet – 85 µg
- Garden cress, raw – 80 µg
- Asparagus, steamed – 78 µg
- Whole grain rye or wheat flour – 40 µg
Gröber, U. (2011): Mikronährstoffe. Metabolic Tuning – Prävention – Therapie. 3. Aufl. Wissenschaftliche Verlagsgesellschaft mbH Stuttgart
Biesalski, H.K., Bischoff, S.C., Pirlich, M., Weidmann, A., (2018). Ernährungsmedizin – Nach dem Curriculum Ernährungsmedizin der Bundesärztekammer (5.Auflage). Stuttgart: Georg Thieme Verlag
Yang Q, Cogswell ME, Hamner HC, et al. Folic acid source, usual intake, and folate and vitamin B-12 status in US adults: National Health and Nutrition Examination Survey (NHANES) 2003-2006. Am J Clin Nutr 2010;91:64-72.