Although vitamin D supplements are widely prescribed and used to benefit bone health, definitive data on whether these supplements reduce fractures in the general population have been inconsistent.
To advance understanding on this subject, researchers from Brigham and Women’s Hospital conducted an ancillary study to the VITamin D and OmegA-3 TriaL (VITAL), a clinical trial of more than 25,000 middle-aged and older adults, also led by investigators from Brigham and Women’s Hospital. The primary endpoint for the ancillary study was incident total, non-vertebral, and hip fractures.
The study was published in the New England Journal of Medicine.
The researchers reported that 1551 of the 25,871 participants had experienced 1991 confirmed incident fractures over a median follow-up of 5.3 years. Compared with placebo, supplemental vitamin D3 (2000 IU/day) did not reduce total fractures – 769 of 12,927 participants in the vitamin D group and in 782 of 12,944 participants in the placebo group (P=0.70) – nor did it affect incident non-vertebral or hip fractures between groups (P=0.50 for non-vertebral fractures and P=0.96 for hip fractures).
In addition, the analyses showed that supplemental vitamin D3 did not affect the number of major osteoporotic fractures, wrist fractures, or pelvic fractures. Effects were not modified by baseline age, sex, race, body mass index, baseline vitamin D blood levels, or personal use of supplemental calcium and/or vitamin D.
“Overall, the results from this large clinical trial do not support the use of vitamin D supplements to reduce fractures in generally healthy US men and women,” said lead author Meryl LeBoff, MD, Chief of the Calcium and Bone Section in the Endocrine Division at the Brigham and Women’s Hospital.
“These findings do not apply to adults with vitamin D deficiency or low bone mass or osteoporosis. Most participants in the trial were not deficient and may have already reached the vitamin D level needed for bone health.
“Our ongoing studies are focusing on whether free vitamin D levels or genetic variation in vitamin D absorption, metabolism, or receptor function will provide information about individuals who may benefit from supplemental vitamin D on musculoskeletal health.”
LeBoff MS, Chou SH, Ratliff KA, et al. Supplemental vitamin D and incident fractures in midlife and older adults. N Engl J Med. 2022 Jul 28;387(4):299-309. doi: 10.1056/NEJMoa2202106.