Vitamins are organic substances that the body need; it obtains and absorbs them from plants and animals. Cobalamin, another name for vitamin B12, is a substance that belongs to the cobalamin family. Deficiency of cobalamin affects the heart uses energy, causing arrhythmia and enlargement of the left ventricle, demyelination, causing neurological symptoms such as numbness, tingling, and difficulty walking Apathy, anorexia, irritability, growth retardation, and developmental regression. Cardiovascular disease (CVD) is the leading cause of mortality in developed countries. It was determined that B12 is an essential micronutrient for a healthy brain in young people and the elderly. Various conditions are responsible for B12 deficiency. If there is a nutritional shortfall, prompt and appropriate supplementation is required. This supplementation can prevent the damage to nervous system. Deficiency may leads to cognitive decline and vascular risk factors in neuropsychiatric disorders, cardiovascular disease, and heart fail. Some cardiovascular or psychological disorders are related to anxiety, dementia and depression, heart attack which can be improved with B12 supplementation.