The effect of a 12-month weight loss intervention on vitamin D status in severely obese Caucasians and African American adults
Year: 2011
Type: article
Study design: Clinical Trial
Abstract: Vitamin D deficiency is a potential risk factor for several chronic conditions, including cardiovascular disease, diabetes and immune disorders. Several studies have found an association between Vitamin D deficiency and obesity, yet it is unclear whether Vitamin D contributes to obesity, or obesity itself causes Vitamin D deficiency. The purpose of this study is to determine the relationship between obesity and Vitamin D status and to examine the effects of weight loss and physical activity on Vitamin D status in severely obese Caucasians and African Americans. 50 class II and class III obese women participated in a 12-month diet and exercise intervention. Vitamin D status was examined at baseline, 6 and 12 months to determine the relationship between Vitamin D and weight loss, fat loss, race and physical activity. At baseline, both the Class I and Class III obese subjects were considered Vitamin D insufficient (20-30 ng/mL). The Class II subjects were considered deficient (<20 ng/mL). The normal weight subjects were classified as sufficient (>30 ng/mL). Caucasians in the Class I and III obese groups had significantly higher Vitamin D than African Americans. Vitamin D increased significantly following 6 months of weight loss. There was no significant relationship between change in Vitamin D and change in body weight or body fat. Vitamin D decreased at 12 months despite a period of weight maintenance yet remained significantly greater than baseline. Meal replacement shakes containing Vitamin D were taken twice per day from baseline to 6 months and once per day from 6-12 months, contributing to the increase in Vitamin D at 6 months and 12 months. Throughout the intervention, Vitamin D status was significantly greater in Caucasians than African Americans. There was no relationship between Vitamin D status and physical activity at 6 or 12 months. The results of this study confirm that Vitamin D deficiency or insufficiency is related to degree of adiposity and is more prevalent in African Americans than Caucasians. Moreover, a dietary weight loss intervention significantly increased Vitamin D in severely obese women, indicating that lower Vitamin D in obesity is amenable to weight loss intervention.
Author: Krista Rompolski
Language: English
Topic: Vitamin D Research Studies
Subfield: Endocrinology, Diabetes and Metabolism
Field: Medicine
Domain: Health Sciences
Open Access status: green
OpenAlex ID: W1575351975