Effects of weight loss on bone turnover, inflammatory cytokines, and adipokines in Chinese overweight and obese adults

Purpose Plenty of studies have examined the long term effect of weight loss on bone mineral density. This study aimed to explore the effects of 10% weight loss on early changes in bone metabolism as well as the possible influencing factors. Methods Overweight and obese outpatients (BMI > 24.0 kg/m(2)) were recruited from the nutrition clinic and followed a calorie-restricted, high-protein, low-carbohydrate diet program. Dietary intake, body composition, serum procollagen type I N-propeptide (PINP), beta-Crosslaps, PTH, 25(OH) VitD, a series of inflammatory cytokines and adipokines were measured for the participants before starting to lose weight and after 10% weight loss (NCT 04207879). Results A total of 75 participants were enrolled and 37 participants achieved a weight loss of at least 10%. It was found that PINP decreased (p = 0.000) and the beta-Crosslaps increased (p = 0.035) in female participants. Decreases in PTH (p = 0.001), serum IL-2 (p = 0.013), leptin (p = 0.001) and increases in 25(OH) VitD (p = 0.001), serum ghrelin (p = 0.033) were found in 37 participants after 10% of their weight had been lost. Change in PINP was detected to be significantly associated with change in lean body mass (r = 0.418, p = 0.012) and change in serum ghrelin(r = - 0.374, p = 0.023). Conclusions Bone formation was suppressed and bone absorption was increased in female subjects after a 10% weight loss. Bone turnover was found to be associated with lean body mass and affected by the circulating ghrelin level.