Letter to Editor about “Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study”

Dear Editor,

We have recently read with great interest the article, “Effect of Vitamin D Supplementation on Weight Loss, Glycemic Indices, and Lipid Profile in Obese and Overweight Women: A Clinical Trial Study” that was written by Khosravi et al.[1] The topic of the study is interesting and the authors tried to shed light on the probable beneficial effect of vitamin D supplementation in overweight and obesity. We would like to correct some aspects of this study. First, we did not see any data about C-reactive protein (CRP) in tables of this paper although the main objective of this study was assessment of the effects of vitamin D supplementation on body weight, other anthropometric measurements, blood pressure, lipid profile, glycemic indices, and CRP among Iranian women and it was mentioned in the results and discussion section. Second, the mean ± SD for waist circumference (WC) in the intervention group was higher than the control group in baseline significantly, although supplementation of the vitamin D reduced significantly the mean of WC, but not adjusted for intervention effect. Third, there was no any guidelines for supplementation of vitamin D in the present study, and the short duration of supplementation may not have significant effects on dependent variables. In addition, the measurement of sun exposure was incorrect because many factors, such as race, skin color, occupation, clothing, season, and other factors, can be effective in exposing to sunlight and receiving vitamin D from sunlight.[2] The present study had major faults and the results are obscure.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.