Methylation is a vitamin-requiring biochemical process in the body that is critical for maintaining mental and physical health. Methylation helps convert the problematic amino acid metabolite homocysteine into the amino acids methionine and cysteine. Consistent recycling of homocysteine is vital for supporting cardiovascular health. Proper methylation can be inhibited by nutrient deficiencies, especially of folic acid, B6 and B12. Certain medications such as acetaminophen, aspirin, ibuprofen and oral contraceptives can also deplete blood levels of these crucial B vitamins, reducing the body’s vital methylation capacity.