Folic acid is one of 13 essential vitamins that can be obtained from dietary sources or supplements. Despite a relative abundance of folic acid in food, its deficiency is frequent and can arise as a consequence of poor diet, chronic illness, drugs, and malabsorption. Folic acid is essential for the functioning of the nervous system. In this new book, the authors present topical research in the study of the properties, medical uses and health benefits of folic acid including the role of folic acid in psychiatric disorders; the importance of folic acid in fertility, miscarriage and preterm birth; the actions of folic acid in the prevention of neural tube defects; folic acid and prostate cancer; photobiological properties of folic acid and how folic acid and B12 supplementation improves the survival of elderly hemodialysis patients.