An adequate intake of the "Sunshine Vitamin," or Vitamin D, might be linked to living a longer life. A large observational study conducted in Austria suggests young and middle-aged adults with low vitamin D levels might live shorter lives.

It found these cohorts with low vitamin D levels in their blood were nearly three times more likely to die during the study period than those with adequate levels. The findings are the result of a 20 year-long follow-up of more than 78,000 Austrian adults.

Vitamin D is produced by the body as a result of exposure to the sun but can also be consumed in food (especially fish) or supplements. An adequate intake of vitamin D results in healthy bones and teeth. It might also protect against type 1 diabetes and multiple sclerosis.

It’s estimated that sensible sun exposure on bare skin for 5 to 10 minutes for two to three times every week produces sufficient vitamin D.

Dr. Rodrig Marculescu, the study lead researcher, and his team found a clear relationship between blood vitamin D levels and the risk of early death, especially among people younger than 60 years old.

People with vitamin D levels of 10 nmol/L (nanomoles per liter) or less had almost a three times higher risk of dying during the study period versus those with adequate levels, which is 50 nmol/L. On the other hand, middle-aged and younger people with vitamin D levels at or above 90 nmol/L had a lower death risk compared to those at the 50 mark.

In general, vitamin D concentrations of 50 nmol/L or higher are considered high enough for overall health, according to the U.S. National Institutes of Health (NIH).

When researchers searched for the causes of death, they found that vitamin D levels showed only weak connections to heart disease and cancer. Instead, people with low levels (below 50 nmol/L) had a more than fourfolds higher risk of dying from diabetes complications compared to those with adequate levels.

However, the findings are considered preliminary. It will be presented this week at the annual meeting of the European Association for the Study of Diabetes in Barcelona.

Experts warn the study findings don't prove low vitamin D levels, per se, cut people's lives short. The research is still evolving.

On the other hand, the new findings add to an already large body of evidence linking inadequate vitamin D to various health effects, the most common of which is thinner, weaker bones. Previous studies have also linked inadequate Vitamin D levels to higher risk of type 2 diabetes and high blood pressure, certain cancers and autoimmune diseases such as multiple sclerosis.

The study did affirm that when it came to the cause of death, vitamin D levels were most clearly linked to deaths from diabetes complications.

"The role of vitamin D in the body appears to be more than simply assisting calcium absorption and bone health," Connie Diekman, a registered dietitian and past president of the nonprofit Academy of Nutrition and Dietetics, said. She wasn't involved in the study.

Diekman said this means it remains unclear if boosting vitamin D intake by eating food or popping pills will prevent various diseases or lengthen lives.

Doctors note that many health conditions such as type 2 diabetes begin earlier in a person's life. It has also been observed that vitamin D supplements might have more of an impact on the odds of dying from a disease.

Higher levels of vitamin D in the blood is associated with a reduced risk of cancer in women over the age of 55. Reuters