Researchers from Germany studied the effect of vitamin D on weight loss and on risk factors associated cardiovascular disease in overweight people.

First, the details.

• 200 healthy overweight people were treated with vitamin D (83 µg/day) or placebo for 12 months.
• Neither the participants nor the researchers knew the treatment given — double-blind.
• The average blood level of vitamin D (25[OH]D) at the start of the study was 30 nmol/L (12 ng/mL).
  • Normal range is 16 to 74 ng/mL.
• Everyone participated in a weight-reduction program.

And, the results.

• Weight loss was not affected by vitamin D supplementation.
• However, vitamin D and calcitriol blood levels increased significantly in the vitamin D group vs placebo.
  • Calcitriol helps regulate and calcium absorption.
• Blood levels of parathyroid hormone, triglycerides, and  tumor necrosis factor-{alpha} decreased significantly more with vitamin D vs placebo.
  • Tumor necrosis factor-{alpha} is used to measure inflammation, which is associated with the risk of heart disease.
• These changes were not related to weight reduction, fat mass, and gender.
• On the negative side, vitamin D supplementation significantly increased LDL (bad) cholesterol levels 5.4% compared to a 2.5% decrease with placebo.

The bottom line?
Vitamin D did not affect weight loss.

Regarding the risk factors for heart disease, the authors concluded, “Vitamin D supplement of 83 µg/day… is able to significantly improve several cardiovascular disease risk markers in overweight subjects with inadequate vitamin D status participating in a weight-reduction program.”

4/20/09 20:56 JR