Men who have low levels of vitamin D are at higher risk of heart attack, researchers presented their findings in an article published in the June 9 issue of “Archives of Internal Medicine.”

It has been found that deaths related to cardiovascular disease are more frequent in higher latitudes and during the winter months and are less frequently at higher altitudes. The body makes vitamin D when the skin is exposed to sunlight. Sunshine is the greatest source of vitamin D. The “sunshine vitamin” helps the body absorb calcium and is considered important for bone health. On a sunny day, just 10 minutes of exposure to sun will generate enough vitamin D to reach the higher levels found protective in the study.

“Those with low vitamin D, on top of just being at higher risk for heart attack in general, were at particularly high risk to have a fatal heart attack,” study author Dr. Edward Giovannucci of the Harvard School of Public Health and Brigham and Women's Hospital in Boston said in a telephone interview, according to Reuters. “Particularly for people who live in the northern-most states and in the winter months, when we don't get a lot of exposure to sunlight, 1,000 to 1,500 units a day of Vitamin D may be warranted.”

Giovannucci and colleagues reviewed the medical records and blood samples of 454 men between the ages of 40 to 75 who had non-fatal heart attack or fatal heart disease, as well as 900 other men with no history of cardiovascular disease. They collected initial data between January 1993 and December 1995. Patients were followed until January 2004.

Vitamin D might lower blood pressure, regulate inflammation, reduce calcification of coronary arteries, affect the heart muscle or reduce respiratory infections during the winter time, Giovannucci said.