Although vitamin D is not an essential nutrient, all humans produce vitamin D when ultraviolet light reaches the skin and reacts with a form of cholesterol known as 7-dehydrocholesterol. Vitamin D deficiencies are not uncommon. Possible reasons for vitamin D deficiency include absorption problems, lack of exposure to sunlight in colder climates or from modern lifestyle practices, which keep many people indoors for most of the day, regardless of the climate in which they live. Vitamin D is involved in bone formation and also has important effects on the nervous system.
Early Years
During brain development in a growing fetus, vitamin D may act like a hormone by controlling nerve transmission, nerve cell protection and immune functions according to an article in the August 2010 issue of the journal "Neuropsychobiology." Deficiency of vitamin D during these crucial early periods of growth can result in delayed or faulty neurologic development and activity. Vitamin D has also been associated with neuropsychiatric disorders; supplementation can prevent or reverse many neurologic conditions associated with low vitamin D.
Later Years
Dementia and Parkinson's disease are neurologic disorders that primarily affect older adults; certain neuromuscular disorders are also more common in this segment of the population. Deficient levels of vitamin D play a role in the development of these conditions. Additionally, a study in the 2010 "Current Drug Targets" discusses the role that vitamin D plays in prevention and treatment of stroke. The researchers identify low vitamin D levels and arterial hypertension as risk factors for stroke and encourage the use of vitamin D as a safe and inexpensive option in the management of this condition.
Chronic Pain
Vitamin D deficiency plays a role in chronic pain disorders, according to a 2008 study in the journal "Pain Medicine." Musculoskeletal pain and neuromuscular dysfunction that does not respond to medication may be due to or associated with vitamin D deficiency. The study documented opiate use of chronic pain patients who were vitamin D deficient compared with a group of chronic pain patients considered to have normal vitamin D levels. The vitamin D deficient group reported worse physical function and an overall perception of their health as being worse than that of the control group.
Women's Health
Inadequate vitamin D status is prevalent in otherwise healthy groups of people, according to a study in the October 2007 issue of the journal "Maturitias." Low vitamin D levels are also often found in patients with neuromuscular weakness and those with osteoporosis or a history of fractures. Women in peri- and postmenopause who are vitamin D deficient are at particular risk for developing neuromuscular weakness due to low estrogen levels and the lack of bone and muscle preserving effects of estrogen.
Autoimmune Conditions
The effect of vitamin D on the immune system was examined with regard to multiple sclerosis (an autoimmune disease that attacks and degrades the insulation around nerve cells) in a study in the October 2010 issue of the "Journal of Immunology." Vitamin D inhibits the production of T cells, a component of the immune system that provides a protective effect and minimizes risk and severity of over-activation of T cells, which occurs in autoimmune conditions.
References
- "Neuropsychobiology": Vitamin D and ageing: neurological issues; Annweiler C, et al.; 2010 Aug
- "Current Drug Targets": Vitamin D Supplementation: A Promising Approach for the Prevention and Treatment of Strokes; Pilz S, 2010 Aug
- "Pain Medicine": Prevalence and clinical correlates of vitamin D inadequacy among patients with chronic pain; Turner MK, 2008 Nov
- "Maturitas": Vitamin D and its implications for musculoskeletal health in women: an update;Pérez-López FR; 2007 Oct
- "Journal of Immunology": Gender Differences in 1,25 Dihydroxyvitamin D3 Immunomodulatory Effects in Multiple Sclerosis Patients and Healthy Subjects; Correale J, Ysrraelit MC, Gaitán MI; 2010 Sept
