Low vitamin D may make you heavier

Low levels of Vitamin D in the body may be responsible for weight gain in women. Vitamin D insufficiency has been linked to low bone mineral density, increased risk of fracture, and obesity in adults. However, this relationship has not been well characterised in young adults. To examine the relationship between serum 25-hydroxyvitamin D, body fat, and bone structure at the time of peak bone mass, researchers from California identified 90 young women, aged 16 to 22 years old, living in sunny southern California. The researchers monitored the vitamin D levels in the participants' body along with their body mass index. Overall, 37 of the 90 women in the study had sufficient concentrations of the vitamin D metabolite 25-hydroxyvitamin D (30 nanograms per milliliter or above). The remaining 53 women had lesser vitamin D metabolite levels suggestive of vitamin D insufficiency. It was found that those with insufficient levels of vitamin D were significantly heavier and had greater body mass than their counterparts with sufficient levels of vitamin D, suggesting that obesity is related to vitamin D insufficiency. There was no association between vitamin D levels and bone measurements in the skeletally mature young women who were between 16 and 22 years old. However, compared with the vitamin D sufficient women, same-age counterparts with insufficient vitamin D levels were heavier by about 7.4 kilograms (approximately 16.3 pounds) on average. The vitamin D insufficient group also averaged 3.4 points higher in body mass measurements. Additionally, the investigators say they found an "unexplained and intriguing" positive link between height and vitamin D status. They, therefore, call for further investigation into this, as well as correlations between vitamin D levels, bone growth, and obesity.