Influences of Select Dietary Components on Bone Volumetric Density, Bone Geometry and Indices of Bone Strength in Young Girls

Abstract

Osteoporosis, a major public health problem, likely has its origins in childhood. During periods of rapid skeletal growth, diet may influence accrual of bone mineral density (BMD) and adult bone health. This study used novel approaches in bone imaging to further characterize optimal skeletal development and enhance our understanding of key dietary components that influence attainment of peak bone mass (PBM) and contribute to determinants of peak bone strength in peri-pubertal females. The use of a validated food-frequency questionnaire (FFQ) enabled the influence of usual dietary intake on bone parameters to be examined.This study examined the relationship of dietary intake of micronutrients and bone macro-architectural structure in peri-pubertal girls. This study suggested that vitamin C and zinc intake are associated with objective measures of bone status in 4th, but not 6th grade girls. This indicates potential differences in micronutrient and bone associations at various age-associated stages of bone maturation.The impact of dietary fat on peri-pubertal skeletal growth is not well characterized. This study examined relationships of select dietary fatty acid (FA) intakes and measures of bone status in peri-pubertal girls. This study suggested that MUFA, total PUFA, n-6 and linoleic acid (LA) are inversely associated with bone status prior to menarche, but composition of dietary fat may be more important during the early-pubertal years. Decreased intakes of n-6 PUFA may benefit bone health in young girls.The impact of a dietary protein on volumetric bone mineral density (vBMD), bone mineral content (BMC) and bone strength throughout maturation remains controversial. Given evidence of both anabolic and catabolic affects of protein on bone health, this study examined relations of dietary protein from different sources with bone parameters in peri-pubertal girls. This study showed that dietary protein intake is related to higher trabecular but not cortical vBMD, BMC and BSI, and accounts for 2-4% of their variability in peri-pubertal girls. The relationship seems to vary by the source of dietary protein and calcium intake. However, a negative impact of animal protein on bone health is not supported. Large scale observational and intervention studies are needed to establish causality.