Vitamin amino acids. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, vitamin E consists of four tocopherols and four tocotrienols. The thirteen vitamins required by human metabolism are: vitamin A (retinols and carotenoids), vitamin B (thiamine), vitamin B (riboflavin), vitamin B (niacin), vitamin B (pantothenic acid), vitamin B (pyridoxine), vitamin B (biotin), vitamin B (folic acid or folate), vitamin B (cobalamins), vitamin C (ascorbic acid), vitamin D (calciferols), vitamin E (tocopherols and tocotrienols), and vitamin K (quinones). Vitamins have diverse biochemical functions. Some forms of vitamin A function as regulators of cell and tissue
Vitamin D treatment or prevention of asthma. Vitamin D and multiple sclerosis incidence have been linked, but it is not clear what the nature of any causal relationship might be. Two systemic reviews concluded that the evidence for vitamin D supplementation being helpful for treating people with multiple sclerosis is inconclusive. Low levels of vitamin D are associated with two major forms of human Inflammatory bowel disease (IBD): Crohn's disease and ulcerative colitis. However, further studies are required to determine its significance and the potential role of vitamin D axis in IBD. Diabetes -- A systematic review of 2014 concluded that the