Vitamin D Deficiency Raises Death Risk

Austrian researchers found people with a Vitamin D deficiency are more likely to die than their counterparts with high levels of the so-called "sunshine" vitamin.

The study found patients with the lowest blood levels of vitamin D were twice as likely to die from any cause during the next eight years than those with the highest levels. 

"This is the first association study that shows vitamin D affects mortality regardless of the reason for death," said Harald Dobnig, an internist and endocrinologist at the University of Graz in Austria who led the study.

Many people have a vitamin D deficiency.

The body naturally makes the "sunshine" vitamin when the skin is exposed to sunlight, and it’s also added to milk and fatty fish like salmon.

Vitamin D aids the body in the absorption of calcium and is considered important for bone health.  Adults can develop osteoporosis and children can develop rickets if they have low levels of vitamin D.

A number of recent studies have also indicated vitamin D may offer a variety of other health benefits, including protection from peripheral artery disease and tuberculosis. Last week, U.S. researchers said vitamin D might lengthen the lives of patients with colon and rectal cancer.

Experts say the research does not mean people should start popping vitamin D pills or spend hours in the sun, the main source for vitamin D.

Doctors say megadoses of vitamin D pills can be dangerous, and too much sunshine can also increase skin cancer risks.  The study did not determine if the lack of vitamin D caused the deaths, or the increase vitamin intake would make a difference.

The study results appeared in Monday’s Archives of Internal Medicine.

Dobnig said the results don’t prove that low levels of vitamin D are harmful "but the evidence is just becoming overwhelming at this point."

American Heart Association spokeswoman Alice Lichtenstein said, low vitamin D levels could reflect age, lack of physical activity and other lifestyle factors that also affect health.

Lichtenstein said, "This is something that should not be ignored," and added its an important addition to a growing area of research.

Austrian researchers led the study that involved 3,258 men and women in southwest Germany.  A majority of participants were about 62 years old who suffered from heart disease. Every week, researchers checked vitamin D levels with blood tests.  After eight years, 737 died, including 463 from heart-related problems.

Results from one of the vitamin tests showed 307 deaths in patients with the lowest levels, versus 103 deaths in those with the highest levels.  Researchers calculated age, physical activity and other factors, and found deaths from all causes were about twice as common in patients in the lowest-level group.

Dobnig said, exactly how low vitamin D levels might contribute to heart problems and deaths from other illnesses is uncertain, although it is has been shown to help regulate the body’s disease-fighting immune system.

Researchers estimate more than 50 percent of older adults worldwide have low vitamin D levels. The trend is also thought to affect substantial numbers of younger people. The study’s authors found decreased outdoor activities, air pollution and, as people age, a decline in the skin’s ability to produce vitamin D from ultraviolet rays contributed to low levels.

Some doctors say an overuse of sunscreen lotions has contributed to the problem. They contend just 10 to 15 minutes spent in the sun without sunscreen is safe and enough to ensure adequate vitamin D.

The Institute of Medicine recommends 200 units of vitamin D daily for children and adults up to age 50, and 400 to 600 units for older adults.

The American Medical Association at its annual meeting last week agreed to urge a review of the recommendations.