Folic acid is a form of the water-soluble vitamin B9. Folic acid is a naturally occurring form of the vitamin, found in food, while folic acid is synthetically produced, and used in fortified foods and supplements. Folic acid is itself not biologically active, but its biological importance is due to tetrahydrofolate and other derivatives such as 5-MTHF, folinic acid etc.
Folate is present in many foods (especially leafy foods, hence the name folic, which stems from the Latin word for LEAF, Folium). It is also present in most green foods such as spinach, broccoli, asparagus, brussel sprouts, and avocados. Some fruits such as bananas, oranges, and peaches also contain folate. Folate may also be found in legumes, peas, lentils, almonds, sunflower seeds, and in various meats such as kidney and liver.
Folate is essential for numerous bodily functions. Humans cannot synthesize folate de novo, therefore, folate has to be supplied through the diet to meet their daily requirements. The human body needs folate to synthesize DNA, repair DNA, and methylate DNA as well as act as a cofactor in certain biological reactions. It is especially important in aiding rapid cell division and growth during pregnancy and infancy. Children and adults both require folate to produce healthy red blood cells and prevent anemia. In the brain, it is also involved in the synthesis of neuro-transmitters and myelin.
A lack of dietary folates can lead to folate deficiency. This deficiency can result in many health problems, the most notable one being neural tube defects in developing embryos. Common symptoms of folate deficiency in adults can include diarrhea, macrocytic anemia, mental depression, and other cognitive deficits. Low levels of folate can also lead to homocysteine accumulation, considered a risk factor in heart disease and disorders of cognition.