Excess of folic acid

See also: folic acid deficiency - folic acid - folic acid quiz - folic acid in pregnancy

Maximum Recommended Intake

The risk of toxicity from excessive folic acid intake is reduced.

According to the "Institute of Medicine's Food and Nutrition Board US, the upper limit uptake for an adult is 1000 mcg per day, compared to a recommended intake of 400 mcg folate / day. The upper limit uptake indicates the maximum daily intake of a nutrient compatible with the absence of side effects from overdose; this value takes into account the total intake, thus adding the food intake with the contribution of any drugs or supplements.

During pregnancy, however, pregnant women who are particularly at risk can take up to 5 mg of folic acid per day, in the form of specific supplements. In these situations, in fact, the achievable benefits in terms of prevention on the closure defects of the neural tube of the unborn child far outweigh the hypothetical risks of a possible overdose.

Folic Acid in Food

Folic acid is contained in dark green leafy vegetables, whole grains, liver, brewer's yeast and fortified foods. Folic acid intakes are therefore generally higher in populations following a vegetarian or raw food diet (good part of the folic acid is lost with cooking) compared to the omnivorous ones.

Health Risks

The most dangerous pitfall of an excessive dietary intake of folic acid is that it tends to hide the early effects of a possible deficiency of B12, a vitamin contained almost exclusively in animal foods.

Therefore, a vegetarian who unfortunately suffers from atrophic gastritis, Crohn's disease, celiac disease or other malabsorption syndromes, may be exposed without his knowledge to the serious consequences of untreated pernicious anemia.

This pathology - determined by the protracted vitamin B12 deficiency - in an advanced stage causes lesions of the nervous system, up to the irreversible degeneration of the posterior cords of the spinal cord, with the appearance of paraesthesia, alterations in sensitivity and motor disturbances up to paralysis.

The consequences that an excess of folic acid can have in certain situations is a further reason to condemn the indiscriminate use of vitamin megadoses, so unconsciously advertised on some internet sites.