Folic acid (vitamin B9): health significance, deficiency symptoms, and natural versus supplemental sources of acquisition

Folic acid, also known as vitamin B9, is an organic compound belonging to the folian group, which is also their active form. The name folic acid comes from the Latin name folium, meaning leaf, and is synthesized in our bodies by gut bacteria.

Folic acid plays an essential role in the metabolism of proteins and DNA, the carrier of genetic information found in every cell. In fetal life, it prevents spinal fracture, a defect that can occur during the first few months of pregnancy.

Excessive folic acid intake is not a risk in healthy people, where even very high doses of vitamins are well tolerated, but they can mask vitamin B12 deficiencies, so a high intake of this vitamin is not recommended for anemia.

Folic acid deficiency in our body can be caused by too little intake of folic acid with food. Other factors can be absorption disorders or increased demand, e.g. pregnant women, infants, teenage girls or elderly people. Alcoholism, smoking, dieting with a caloric deficit and diseases such as chronic kidney disease, Crohn's disease, psychosis.

Natural folia found in food are folic acid salts. A rich source of these compounds is primarily dark green leafy vegetables such as spinach, Brussels sprouts, broccoli, green peas or cauliflower, but also wheat kernels and grain sprouts. Sources can also be found in animal products such as liver and eggs. It should also be noted that the folia contained in the food are very sensitive to high temperatures, so preserving the richness of those compounds should avoid long-term cooking of flavourings.