New research shows that chronic vitamin D deficiency may be a factor in heart disease, high blood pressure and metabolic syndrome, and that vitamin D benefits definitely include protecting heart health.
Known as the “sunshine vitamin” because exposure to sunlight triggers the body to synthesize it, vitamin D has long been recognized as crucial to the development and maintenance of strong bones. But new studies and reviews are indicating vitamin D deficiencies are an important indicator of heart disease risk as well.
Low vitamin D levels related to incidence of heart attacks and heart disease
A 2008 Loyola University review cited a number of studies that link low levels of vitamin D to heart-related problems, noting that the rates of severe disease and mortality may be as much as 30 to 50 percent higher among heart disease patients who are sun-deprived.
In addition, a recent Harvard study concluded that low levels of vitamin D appear to be associated with higher risk of heart attack in men. The study used research statistics that show the rates of cardiovascular disease-related deaths are increased when exposure to vitamin D producing sunlight is reduced (at higher latitudes and during the winter months), but those same rates go down in conditions when exposure to sunlight is increased.
The study also compared medical records and blood tests from a group of several hundred men who had suffered a heart attack to those of men who had not suffered heart problems. The comparison indicated that men with a vitamin D deficiency (quantified as 15 nanograms per milliliter of blood or less) had an increased risk for heart attack compared with those with a sufficient amount (having 30 nanograms per milliliter of blood or more) of vitamin D.
Even a slight deficiency of vitamin D appears to raise the risk of cardiac problems. According to the study, men with intermediate levels of vitamin D had a higher risk of heart attack than those with sufficient vitamin D levels.
Screening and treatment for vitamin D deficiency recommended
A 2008 research paper published in the Journal of the American College of Cardiology called vitamin D deficiency “an unrecognized, emerging cardiovascular risk factor, which should be screened for and treated.” The paper endorsed practical recommendations to screen for and treat low vitamin D levels, especially in patients with risk factors for heart disease or diabetes.
“Vitamin D deficiency is an unrecognized, emerging cardiovascular risk factor, which should be screened for and treated,” said James H. O’Keefe, M.D., cardiologist and director of Preventive Cardiology at the Mid America Heart Institute, Kansas City, MO. “Vitamin D is easy to assess, and supplementation is simple, safe and inexpensive.”
It is estimated that up to half of U.S. adults and 30 percent of children and teenagers have vitamin D deficiency, which predisposes them to hypertension and a stiffening and thickening of the heart and blood vessels. Vitamin D deficiency also alters hormone levels and immune function, which can increase the risk of diabetes and cardiovascular disease.