Vitamin D's Impact on Health: New Study Suggests Body Weight Matters - SciTechDaily

Individuals with a higher BMI showed a weakened response to vitamin D supplementation, which could explain disparities in outcomes such as cancer, diabetes, and autoimmune diseases.

The findings, published in JAMA Network Open, come from a reanalysis of data from the VITAL trial, a nationwide clinical study led by Brigham researchers that explored the impact of vitamin D and marine omega-3 supplements on reducing the risk of cancer, heart disease, and stroke.

“The analysis of the original VITAL data found that vitamin D supplementation correlated with positive effects on several health outcomes, but only among people with a BMI under 25,” said first author Deirdre K. Tobias, ScD, an associate epidemiologist in Brigham’s Division of Preventive Medicine.

“There seems to be something different happening with vitamin D metabolism at higher body weights, and this study may help explain diminished outcomes of supplementation for individuals with an elevated BMI.”

“Most studies like this focus on the total vitamin D blood level,” said senior author JoAnn E. Manson, MD, DrPH, chief of the Division of Preventive Medicine at the Brigham and principal investigator of VITAL.

Pharmavite LLC of Northridge, California (vitamin D) and Pronova BioPharma of Norway, and BASF (Omacor fish oil) donated the study agents, matching placebos, and packaging in the form of calendar packs.