JCEM: Effects of vitamin D3 supplementation on body composition

Although observational studies have shown a negative correlation between vitamin D status and weight/obesity, few large randomized controlled trials (RPTs) have investigated this relationship.
recently, a study published in Journal of Clinical Endocrinology and Metabolism, an authoritative journal in the field of endocrine and metabolic diseases, aims to clarify whether vitamin D3 supplementation can reduce weight or improve body composition.
vitamin D and OmegA-3 trials (VITAL) were a two-blind, placebo-controlled randomized controlled trial that included 25,871 U.S. adults.
the study was done in a sub-queue that performed a body composition assessment in baseline and 2-year follow-up.
participants were 771 participants (male≥ 50 years old and female ≥ 55 years old).
the study was designed for 2×2 factors: vitamin D3 (2000 IU/day) and/or omega-3 fatty acids (1 g/day).
the study's main outcome indicators were changes in body weight, body mass index (BMI), waist circumference and sum/or regional fat and lean tissue measurements over a 2-year period measured by the bier energy x-bone density meter.
researchers looked at the effects of clinical variables and total free 25-hydroxyvitamin D (25(OH)D) levels.
vitamin D3 had no effect on weight, BMI or obesity and lean tissue indicators compared to placebo.
effect does not vary by gender, race, fat mass index, or baseline total or free 25 (OH) D level.
vitamin D3 supplementation improved slightly in body fat rates in normal baseline BMI participants, but did not improve in overweight or obese participants (interaction P-0.04).
in the elderly, daily vitamin D3 supplementation did not improve weight or body composition compared to placebo.
whether vitamin D3 supplementation is good for normal individuals with BMI is worth further study.