Serum 1,25-dihydroxy vitamin D is inversely associated with body mass index

Eur J Nutr. 2008 Mar;47(2):87-91. doi: 10.1007/s00394-008-0700-4. Epub 2008 Mar 4.


Background: Based on in vitro studies, it has been hypothesized that 1,25-dihydroxy vitamin D (1,25-vit D) may promote weight gain in humans, but previous studies have demonstrated conflicting results regarding the association between serum 1,25-vit D and body mass index (BMI).

Aim of the study: To evaluate the relation between serum 1,25-vit D and BMI.

Methods: Two thousand one hundred and eighty-seven subjects, recruited from a metabolic and medical lifestyle management clinic, were included in a cross-sectional study. BMI, 25-hydroxy vitamin D (25-OH-vit D) and 1,25-vit D were measured. The cohort was divided according to BMI in five groups (<25, 25-29.9, 30-34.9, 35-39.9 and >39.9 kg/m(2)). Statistical analyses were performed with multiple linear regression models. Age and gender were used as explanatory covariates.

Results: With increasing BMI group, there was a significant decrease in both serum 25-OH-vit D and 1,25-vit D (P<0.001). Those with BMI >39.9 kg/m(2) had 24% lower serum 25-OH-vit D levels and 18% lower 1,25-vit D levels than those with BMI <25 kg/m(2).

Conclusions: There is an inverse association between BMI and the serum levels of 25-OH-vit D and 1,25-vit D. This makes it highly unlikely that high levels of circulating 1,25-vit D contribute to the development of obesity.

MeSH terms

  • Adult
  • Age Factors
  • Body Mass Index*
  • Cross-Sectional Studies
  • Female
  • Humans
  • Linear Models
  • Male
  • Middle Aged
  • Obesity / blood*
  • Sex Factors
  • Thinness / blood
  • Vitamin D / analogs & derivatives*
  • Vitamin D / blood


  • Vitamin D
  • 1,25-dihydroxyvitamin D
  • 25-hydroxyvitamin D