Intermountain Medical Center research shows benefits of vitamin D

SALT LAKE CITY — People who are deficient in vitamin D and raise their intake — through supplements or more sun exposure — can cut their risk for heart disease and a host of other chronic conditions, according to new research from Intermountain Medical Center.

Researchers found that raising the amount of vitamin D in the blood can help some people reduce the risk of heart disease by 30 percent. Recent studies have shown that as many as three-quarters of Americans have a concentration of vitamin D in their blood that is below normal.

"The question we looked at is, if you do something about it, like taking vitamin-D supplements, does that reduce the risk?" said Dr. J. Brent Muhlestein, the lead author of the study and director of cardiovascular research at Intermountain's Heart Institute. He and his colleague Dr. Heidi May found that "there is a reduced risk of cardiovascular death after patients knew their level was low and did something to normalize it."

More than 40,000 patient records were examined during two Intermountain Medical Center studies to come up with the new correlation. The research was presented publicly for the first time Monday during the American College of Cardiology's annual conference in Atlanta.

Muhlestein said the level of vitamin D that long has been recommended probably is not optimal. "If you want to eliminate any association between your level of vitamin-D levels and cardiovascular disease risk, you probably want to attain 43 (nanograms per milliliter of blood or higher)," he said.

In the study, patients who had those levels had lower rates of death, diabetes, cardiovascular disease, myocardial infarction, heart failure, high blood pressure, depression and kidney failure.

To date, a level of 30 nanograms of vitamin D per milliliter of blood has been considered "normal," he said.

For the first study, researchers followed two groups of patients for an average of one year. More than 9,400 patients, mostly female, reported low initial vitamin-D levels and had at least one follow-up exam during that time period. Researchers found that the 47 percent of the patients who increased their levels of vitamin D between the two visits showed a reduced risk for cardiovascular disease.

In the second study, researchers put more than 31,000 patients into three categories, based on their levels of vitamin D, and examined what happened to those who increased their vitamin D levels to 43 nanograms per milliliter of blood or higher.