The study, published in the June 23, 2008 issue of the Archives of Internal Medicine, found that patients with the lowest blood levels of vitamin D were about two times more likely to die from any cause during the next eight years than those with the highest levels. The link with cardio-related deaths was particularly strong in those with low vitamin D levels.
It has been estimated that 50 to 60 percent of people do not have satisfactory vitamin-D status. The lack of the vitamin can be caused by factors such as urbanization, demographic shifts, decreased outdoor activity, air pollution and global dimming, and decreases in the cutaneous production of vitamin D with age.
The study led by Austrian researchers involved 3,258 men and women in southwest Germany with an average age of 62 years on average. Participants with heart disease got their vitamin D levels checked in weekly blood tests for nearly eight years.
The results found that 737 died, including 463 from heart-related problems. There were 307 deaths in patients with the lowest levels, versus 103 deaths in those with the highest levels, the researchers found using a new test.
However, the researchers have also added that high doses of this vitamin can also be dangerous and prolonged exposure to sun can also lead to skin cancer risks. It is still not clear that exactly how low vitamin D levels might contribute to heart problems and deaths from other illnesses. The sunshine vitamin is also shown to help regulate the body's disease-fighting immune system.
The minimum desirable serum level of 25-hydroxyvitamin D has been suggested to be 20 to 30 ng/mL, and levels lower than this are clearly related to compromised bone-mineral density, falls, and fractures and more recently have also been linked to cancer and immune dysfunction, as well as cardiovascular disease, hypertension, and metabolic syndrome, the authors report.
