Deficiency of vitamin D has been associated with increased risk of heart disease. But a new study has challenged this belief that vitamin D deficiency from lack of sunshine can cause the same in winters.

Study’s leader Emeritus Professor Hugh Tunstall-Pedoe from Dundee University said vitamin D level is not important when it comes to cardiovascular disease and winter deaths. It could be having roles to play in other disease.

In 1981, vitamin D was first linked with excess winter disease. It was also the year when the Cardiovascular Epidemiology Unit in Ninewells Hospital in Dundee was started with aim to study the reasons of the excess heart disease in Scotland.

A number of men and women at that time agreed to have their risk factors measured and their medical records were also followed. In the latest study, the researchers assessed their saved blood for vitamin D. The researchers found that incidences of cardiovascular events do not change seasonally, but deaths from heart disease and other causes have.

Vitamin D levels did vary and they were at highest levels in August and lowest in March. Lower vitamin D levels were associated with higher rates of cardiovascular disease and also with lifestyle and other risk factors.

The researchers said that people with low vitamin D levels do not have a greater increase in winter disease rates in comparison to others. “If vitamin D deficiency were a major cause of heart disease and death, we would have expected it to show up. But it did not. So our results seriously challenge its alleged role”, said the researchers.