Folic acid, also known as folate, is a B-vitamin that is essential for several bodily functions. One of its primary roles is to support the production and maintenance of new cells in the body. Adequate intake of folic acid is particularly important during pregnancy, as it helps prevent birth defects in the brain and spine of the developing fetus. Additionally, folic acid may help lower the risk of heart disease, stroke, and some types of cancer. It also plays a role in the metabolism of amino acids and the synthesis of neurotransmitters, which are essential for proper brain function. People who take methotrexate also take folic acid to reduce the risk of methotrexate-related side effects and toxicity.