PTH and Obesity: Intracellular calcium promotes lipogenesis and potentially reduces catecholamine-induced lipolysis.16 In fact, PTH has been postulated as an independent predictor of obesity; however, this hypothesis has been considered highly controversial, as weight loss in these individuals is associated with a normalization of vitamin D and PTH serum levels; that means, it rather seems as a consequence, not a cause, of excess body weight.10