Emory Report homepage  

October 27, 2008
Lack of vitamin D linked to Parkinson’s disease

By Quinn Eastman

A majority of Parkinson’s disease patients had insufficient levels of vitamin D in a study published in the October issue of Archives of Neurology.

The fraction of Parkinson’s patients with vitamin D insufficiency, 55 percent, was significantly more than patients with Alzheimer’s disease (41 percent) or healthy elderly people (36 percent).

The finding adds to evidence that low vitamin D is associated with Parkinson’s, says neurologist Marian Evatt, assistant director of the Movement Disorders Program at Wesley Woods Hospital.

“We found that vitamin D insufficiency may have a unique association with Parkinson’s, which is intriguing and warrants further investigation,” Evatt says.

The connection could come partly because patients with Parkinson’s have mobility problems and are seldom exposed to the sun, or because low vitamin D levels are in some way related to the genesis or progression of the disease.

Most Americans get the majority of their vitamin D from exposure to sunlight or dietary supplements, with fortified foods as a minor source. Only a few foods in nature contain substantial amounts of vitamin D, such as salmon and tuna.

The body’s ability to produce vitamin D using UV-B radiation from the sun decreases with age, making older individuals at increased risk of vitamin D deficiency.

Doctors have known for decades that vitamin D plays a role in bone formation. More recently, scientists have been uncovering its effects elsewhere, including producing peptides that fight microbes in the skin, regulating blood pressure and insulin levels, and maintaining the nervous system.