High vitamin D and calcium intakes increase bone mineral content in diet‐induced obesity (1029.3)

Abstract

Obesity can be detrimental to health of the growing bone, including an increased risk of bone fractures, because it is often associated with low vitamin D and calcium status. In this study, we determined effects of vitamin D and calcium supplementation on bone mineral content and blood biomarkers of Ca2+, vitamin D and bone metabolism in diet‐induced obese mice. Four‐week‐old male C57BL/6J mice were fed for 10 weeks either a high fat (HF) diet (60% energy from fat) or HF diets containing 1.2% Ca, 10000 IU/kg vitamin D3 and their combination. The results obtained demonstrated that high Ca and vitamin D intakes increase bone Ca and P content and have no effect on bone collagen (hydroxyproline) content, as compared with the HF diet group. High vitamin D3 intake significantly increased plasma concentrations of Ca2+, 25(OH)D, 1,25(OH)2D and decreased concentration of parathyroid hormone (PTH) and osteocalcin in HF diet‐fed mice. High Ca intake suppressed PTH but also increased plasma Ca2+. These findings suggest that the vitamin D and Ca supplementation improves bone status in obesity by increasing bone mineralization and, probably, suppressing bone resorption via PTH/1,25(OH)2D axis.Grant Funding Source: Supported by USDA 2009‐35200‐05008 and SD00H325 to I.N.S..