Vitamins are necessary factors in human development and normal brain function. Vitamin C is a hydrosoluble compound that humans cannot produce; therefore, we are completely dependent on food intake for vitamin C. Ascorbic acid is an important antioxidative agent and is present in high concentrations in neurons and is also crucial for collagen synthesis throughout the body. Ascorbic acid has a role in modulating many essential neurotransmitters, enables neurogenesis in adult brain and protects cells against infection. While SVCT1 enables the absorption of vitamin C in the intestine, SVCT2 is primarily located in the brain.
Ascorbate deficiency is classically expressed as scurvy, which is lethal if not treated. However, subclinical deficiencies are probably much more frequent. Potential fields of vitamin C therapy are in neurodegenerative, cerebrovascular and affective diseases, cancer, brain trauma and others. For example, there is some data on its positive effects in Alzheimer’s disease. Various dosing regimes are used, but ascorbate is safe, even in high doses for protracted periods. Better designed studies are needed to elucidate all of the potential therapeutic roles of vitamin C.