Vitamin C contributing to the more severe symptoms of scurvy. More generally, the biochemical role of vitamin C is to act as an antioxidant (a reducing agent) by donating electrons to various enzymatic and non-enzymatic reactions. Doing so converts vitamin C to an oxidized state - either as semidehydroascorbic acid or dehydroascorbic acid. These compounds can be restored to a reduced state by glutathione and NADPH-dependent enzymatic mechanisms. In plants, vitamin C is a substrate for ascorbate peroxidase. This enzyme utilizes ascorbate to neutralize toxic hydrogen peroxide (HO) by converting it to water (HO). Scurvy is a disease resulting from a deficiency
Vitamin B12 age, thereby increasing their probability of B deficiencies. Vitamin B deficiency can also cause symptoms of mania and psychosis. Vitamin B deficiency is most commonly caused by low intakes, but can also result from malabsorption, certain intestinal disorders, low presence of binding proteins, and use of certain medications. Vitamin B is rare from plant sources, so vegetarians are more likely to suffer from vitamin B deficiency. Infants are at a higher risk of vitamin B deficiency if they were born to vegetarian mothers. The elderly who have diets with limited meat or animal products are vulnerable populations as well. Vitamin