Vitamin D supplementation recently has been in the spotlight, when a study suggested that Vitamin D supplementation might decrease mortality regardless of cause.

Humans obtain vitamin D from a variety of sources including sunlight, dietary supplements and certain foods such as oily fish and milk. When there is an extreme lack of vitamin D, rickets or osteomalacia — bones softening — develops. One sign of rickets is by improper bone development and problems with calcium and phosphorus metabolism. Isolated or generalized bone pain could be a sign of osteomalacia. While only a small percentage of the world’s population develop these extreme forms of vitamin D deficiency, research determined that more than 90 percent of people admitted to emergency rooms with muscle aches, pain, fibromyalgia, chronic fatigue and depression were deficient in vitamin D.

Areas of the world at higher latitudes, such as the Pacific Northwest, have strong variations in day length and the sun’s angle. This causes people to have less exposure to direct sunlight during the winter months. Residents of these areas, people with darker skin pigmentation, people who spend most of their time indoors and those whose culture encourages them to cover much of their exposed skin, are all at increased risk for vitamin D deficiency.

Nursing home residents are at especially high risk, however, and even among a group of healthy students and physicians who drank milk regularly, took a multivitamin and ate salmon once a week, a third were vitamin D deficient. Other people at risk include those with malabsorption diseases (e.g., Crohn’s disease), liver disease, chronic kidney disease and obesity.

Vitamin D receptors exist in most tissues and cells of the body and might play a role in decreasing the risk of many chronic illnesses including common cancers, autoimmune diseases such as multiple sclerosis, type 1 diabetes, infectious diseases and cardiovascular disease.

Vitamin D and calcium supplementation has been shown to significantly increase bone density and reduce fractures. Muscle strength improves with vitamin D supplementation, and several studies have confirmed a decrease in falls when vitamin D intake was increased.

Other benefits include a reduced risk of several types of cancer. Many studies have been performed to link vitamin D deficiency or supplementation with overall mortality. In 2007, a study was done examining the effect of vitamin D supplementation on dying from any health condition. The researcher found a significantly lower risk of death from any cause when a person took an average vitamin D dose of 528 milligrams per day.

While this information does not guarantee that taking vitamin D will extend your life, it does create a strong argument that adding a little extra vitamin D to your diet might benefit you in the long run and is not harmful. Talk to your health care provider to determine if you need testing and to decide which form of vitamin D may be best for you.

Andrew Freeman is a fourth-year Pharm.D. student at Oregon State University. Rachelle Younger is a Pharm.D. pharmacy practice resident at Good Samaritan Regional Medical Center and Jacqueline Joss is a Pharm.D., clinical pharmacist at Good Samaritan Regional Medical Center.