Lower dairy calcium and dairy vitamin D intakes are associated with increased skeletal muscle fatty infiltration in adolescent girls

Abstract

BACKGROUNDFat infiltration within skeletal muscle is strongly associated with type 2 diabetes mellitus. Insufficient calcium (Ca) and vitamin D (VitD) intake is common in youth and has been associated with the development of obesity and osteoporosis. Dairy Ca and VitD are better absorbed compared to other dietary sources and have been linked to decreased adiposity.OBJECTIVEExamine the relationships between dairy Ca and VitD with skeletal muscle fat infiltration (SMFI) in 212 healthy girls aged 8–13 years.METHODSMuscle density (mg/cm3), an index of fat infiltration, was measured at the 66% tibia and 20% femur sites (relative to distal growth plates) on the non‐dominant limb using peripheral quantitative computed tomography (pQCT). Dairy Ca and VitD were assessed using the Harvard youth adolescent questionnaire (YAQ).RESULTSMultiple linear regressions with dairy Ca and VitD, maturity, total caloric intake, and activity (pedometer steps) were used to predict SMFI and showed that dairy Ca was positively associated with muscle densities of the calf (P ≤ 0.01, partial r (ρ)=0.185, β=0.216) and thigh (P ≤ 0.05, ρ=0.135, β=0.157 ). Dairy VitD was independently associated with higher muscle densities of the calf (P≤ 0.01, ρ=0.183, β=0.194) and thigh (P ≤ 0.05, ρ=0.159, β=0.168).CONCLUSIONLower dairy consumption is associated with increased SMFI in young girls.Grant Funding Source : NIH: HD050775