The research concludes that people who have suffered from cardiovascular disease, and have a normal intake of vitamin D, reduce their risk of morality as a consequence of the disease by 30 per cent.
"We discovered that the right amount of vitamin D reduces the risk of death substantially. However, too much or too little increase the risk," said Jutta Dierkes from the University of Bergen in Norway.
Researchers followed as many as 4,000 patients with cardiovascular diseases from year 2000, for a period of 12 years.
The study, published in The Journal of Clinical Endocrinology & Metabolism, showed that it is favourable to have blood values around 42 to 100 nanomoles per litre (nmol/l). If you have higher or lower values, you are at greater risk of dying from cardiovascular disease.
According to Dierkes, it is difficult to give general a recommendation of how much vitamin D supplementation one should take.
"The optimal amount of vitamin D-supplement varies from one person to another. It depends where you live, and what kind of diet you have," Dierkes said.