Vitamin D Levels In This Form Can Predict Future Health Risks Better, Says Study

Vitamin D levels in the blood can forecast future health risks in aging men, says a new study. Researchers say the free, circulating form of vitamin D level found in the bloodstream can predict future health risks rather than its total measure.

Vitamin D is crucial for maintaining healthy bones and teeth, to protect against infections and diseases and keep muscles healthy. It also aids in the absorption of calcium and phosphate in the body. Since there are hardly any food items that contain the natural form of this vitamin, its deficiency is highly prevalent across the world. Estimates suggest that approximately one billion people throughout the world have low levels of vitamin D in their blood.

Researchers from University Hospitals Leuven in Belgium found that the free, the precursor form of the sunshine vitamin found circulating in a person's bloodstream can accurately predict future health and disease risks rather than the total measure of the vitamin in the body. The findings will be presented at the ongoing e-ECE 2020 seminar.

The precursor of vitamin D found in blood, 25-dihydroxyvitamin D, gets converted to 1,25-dihydroxyvitamin D ( the hormonally active form of vitamin D3 ), which is considered the active form of the vitamin present in the human body. Over 99% of all metabolites of vitamin D in the blood are bound to proteins and therefore, only a tiny fraction of it is allowed to be biologically active. This explains why the free, active forms of the vitamin might predict current and future health.

In the study, the researchers analyzed data collected from 1,970 community-dwelling men in the age group 40-79, from 2003 to 2005 to find out whether the free metabolites of vitamin D help predict future health conditions. They compared the levels of the bound and free metabolites of vitamin D with their current health status.

Even though both free and bound vitamin D metabolites were linked to a higher risk of death, the researchers found that only 25-hydroxyvitamin D helped predict future health conditions.

The findings also confirmed that vitamin D deficiency negatively impacted people's general wellbeing and that it can be predictive of a higher risk of death. As the study was observational in nature, it couldn't determine the underlying mechanisms and obtain specific information pertaining to the cause of death in the participants.

"Most studies focus on the association between total 25-hydroxyvitamin D levels and age-related disease and mortality. As 1,25-dihydroxyvitamin D is the active form of vitamin D in our body, it was possible it could have been a stronger predictor for disease and mortality. It has also been debated if the total or free vitamin D levels should be measured," said Dr. Leen Antonio from University Hospitals Leuven in a news release.

"Our data now suggest that both total and free 25-hydroxyvitamin D levels are the better measures of future health risk in men," he added.