Vitamin A is essential for many physiological processes and is particularly crucial during early life, when vitamin A deficiency increases mortality through elevated rates of infection. This deadly aspect of vitamin A deficiency masks other effects that, while not lethal, may nevertheless cause significant issues if vitamin A insufficiency reoccurs during later childhood or in the adult. One such effect is on the brain. Vitamin A is essential for several regions of the brain, and this chapter focuses on two regions: the hippocampus, needed for learning and memory, and the hypothalamus, necessary to maintain the body's internal physiological balance. Vitamin A, through its active metabolite retinoic acid, is required to support neuroplasticity in the hippocampus, and vitamin A deficiency has a dramatic effect on depressing learning and memory. The effects of vitamin A deficiency on the hypothalamus may lead to depression of appetite and growth. Much of this research has relied on animal studies, and it will be essential in the future to determine the full role of vitamin A in the human brain.
- Journal Article