Does Lack Of Vitamin D Cause Depression?

Vitamin D plays a major role in the health of every individual, affecting every organ system. Although the body can manufacture the nutrient from exposure to intense sunshine, many people are vitamin D deficient, and this can affect health in a number of ways. Depression can be one outcome.

Vitamin D

Manufactured in the skin following exposure to sunlight or obtained through the diet from foods like oily fish, vitamin D affects the expression of more than 2,000 genes in the human body. The National Institutes of Health points out that the nutrient, also known as cholecalciferol, converts into a storage formed called calcidiol before undergoing conversion into calcitriol, the active form of vitamin D.

Seasonal Sunlight

"Bostonia," a magazine produced by Boston University, points out that vitamin D takes a unique place in human nutrition as the one essential nutrient that you can obtain from sunlight alone. As a consequence, blood levels of vitamin D in most individuals fall during the winter months. The magazine notes that, in northern cities such as Boston, humans cannot produce vitamin D from sunlight between November and March.

Deficiency

Dr. Joseph Mercola, a U.S. physician and the author of "The No Grain Diet," explains that the body cannot produce vitamin D without high-intensity sunshine, leaving the vitamin content of foods as the only source during the winter months. He believes that the majority of the American population suffer from the symptoms of vitamin D deficiency, including depression. Incidences of deficiency increase in winter; those suffering from depression at this time may benefit from considering their vitamin D status.

Depression

A variety of factors can contribute to depression, and the range of treatment methods for this condition reflect this. Dr. John Holick, a research scientist and the head of the Vitamin D Council, explains that vitamin D can act as one such factor and identifies a wealth of scientific studies that document a link between low levels of vitamin D and depression. One such study, conducted at the University of Bonn and published in the "British Journal of Nutrition" in 2003, found that levels of vitamin D metabolites predicted rates of depression across a range of experiments. However, Dr. Holick points out that the nutrient does not represent a panacea for this serious condition, and that other factors should also be considered.

Vitamin D Effects

Holick believes that the link between vitamin D levels and depression lies in the function of the tyrosine hydroxylase enzyme, which remains fully dependent on the availability of the nutrient. This enzyme produces dopamine, an important neurotransmitter that can improve energy levels and mood. With this in mind, Holick notes that vitamin D may help seasonal affective disorder, but more research is required on its effects in cases of major depression.