Magnesium Status and Bone Mineral Density in Obese and Overweight Adults

Résumé du livre

Overweight and obese individuals have an altered bone metabolism. Increased serum parathyroid hormone (PTH) concentrations and low serum concentrations of 25- hydroxyvitamin D (25OHD), which are important contributors to poor bone quality in this population. Magnesium (Mg) is an important micronutrient whose deficiency can result in elevated serum PTH concentrations and decreased serum 25OHD concentrations. The main purpose of this study was to determine the relationship bet ween Mg status, including serum ionized Mg and dietary Mg intakes, and bone mineral density (BMD) and bone regulating hormones in overweight and obese individuals. Magnesium intakes were examined using a newly developed Mg food frequency questionnaire. Serum was assayed for concentrations of ionized Mg, PTH and 25OHD and other markers of bone turnover. Bone mineral density was evaluated using a dual energy absorptiometry (DXA) at the hip, lumbar spine, forearm and total body. Our results in 27 adults show that magnesium intake is a significant positive contributor to serum 25OHD concentrations (r=0.392 p=0.039). Ionized Mg concentrations and dietary Mg intakes did not predict BMD but Mg intake had a positive association with BMC at the l/3rd radius. Ionized magnesium concentrations was also positively correlated with serum PTH concentrations (r=0.436, p=0.042), however when included in a linear regression model along with BMI and age, PTH was no longer an independent predictor of ionized Mg. In summary, our findings suggest that dietary magnesium intake is a regulator of serum 25OHD concentrations in the overweight and obese population.