Vitamin D deficiency linked to increased heart risk

Recent studies have indicated that vitamin D may help to prevent cancer, strengthen bones, slow aging and ward off Tuberculosis. And now, according to a study at Harvard Medical school, people with a vitamin D deficiency could face up to twice the risk of a heart attack or stroke than those with higher levels of the vitamin.

The study, published in the journal Circulation, suggests that people with moderate to severe vitamin D deficiency have a risk "above and beyond" other well known cardiovascular risk factors such as high cholesterol and diabetes.

And for people with both high blood pressure and vitamin D deficiency, the risk appears especially high. When researchers isolated 688 study participants who had blood pressure, they found that this group had twice the risk of cardiovascular problems as other participants.

"Vitamin D deficiency is associated with increased cardiovascular risk, above and beyond established cardiovascular risk factors," said lead author Dr. Thomas J. Wang, assistant professor of medicine at Harvard Medical School. "The higher risk associated with vitamin D deficiency was particularly evident among individuals with high blood pressure."

The study, which involved 1,739 people with an average age of 59, was conducted between 1996 and 2001. After high cholesterol, diabetes and other risk factors were taken into account, people with lower vitamin D levels (below 15 nanograms per millilitre) had a 62 per cent increased risk of developing cardiovascular problems such as a heart attack, heart failure or stroke in the five years following than those with higher blood levels of the vitamin.

"We found that people with low vitamin D levels had a higher rate of cardiovascular events over the five-year follow-up period," Dr. Wang said. "These results are intriguing and suggestive but need to be followed up with further study."