Researchers found those with low blood levels of the "sunshine vitamin" were twice as likely to suffer heart failure, a heart attack or a stroke than those with higher levels.

The risk was still 62 percent after adjusting for well-established risk factors such as high blood pressure and high cholesterol.

Dr. Thomas Wang, who led the research, said: "Our data raises the possibility that treating vitamin D deficiency, via supplementation or lifestyle measures, could reduce cardiovascular risk."

The five-year study, published in the journal Circulation, involved 1,700 sons and daughters of the participants in the Framingham Heart Study, which was a major investigation of heart disease risk factors launched back in 1948.

Most of the body's supply of vitamin D is provided by sunlight on the skin. The rest comes from foods such as fish, eggs, fortified milk and breakfast cereals. The mechanism by which it works is only partly understood, but vitamin D has been shown to slow the rate of growth of cancer cells and may boost the function of blood vessels or the immune system.

Although most of those living in northern North America or northern Europe are not sufficiently lacking in vitamin D to be classified as deficient, some experts believe blood levels should be higher to optimize health.

Only 10 percent of the study sample had levels considered ideal, even for bone health.

A spokesman for the UKs Health Supplements Information Service said: "Dietary surveys show that large numbers of people in northern climates have blood levels of vitamin D which are too low. Diet does not provide enough vitamin D and the need for each of us to expose our skin to sunlight for short periods of time runs contrary to advice to avoid sunbathing to the reduce risk of skin cancer."

Confusing messages, combined with seasonal variation in UV radiation strength, geographic latitude, time of day, cloud cover and use of sunscreen merge to hamper reliable vitamin D synthesis.

Source: Daily Mail; London (UK). Provided by ProQuest Information and Learning. Powered by Yellowbrix.

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