Calcium homeostasis may influence resting energy expenditure with effects most apparent in early pubertal girls

Abstract

Perturbations in dietary and hormonal components of the calciotropic network may be mediated through the influence of calcium homoeostasis on resting energy expenditure (REE). We investigated the association of dietary and hormonal factors involved in the regulation of calcium homoeostasis with REE in girls. Thirty-six girls aged 7-11 years participated. REE was assessed by indirect calorimetry, and body composition, dietary intake (calcium, vitamins D and K, phosphorus) and serum hormones (PTH, osteocalcin, 25OHD) were evaluated by DXA, 24 h recall and serum assay, respectively. A positive association between vitamin K and REE and an inverse association of parathyroid hormone (PTH) with REE (p = 0.05) were observed. PTH and REE were positively related in those having normal adiposity (p = 0.03) and inversely related in those with excess adiposity (p = 0.01). The association of REE with vitamin K intake was evident in lean individuals (p = 0.001), but was null in those with excess adiposity. Decreased calciotropic hormone levels along with increased related nutrient intakes were associated with greater REE, although these relationships differed according to adiposity. The physiologic response to the diet and subsequent energy partitioning needs to be considered in the context of puberty. In particular, regulation and signalling of the calciotropic network during pubertal maturation warrant investigation.