Effects of fiber enriched high carbohydrate diet (FEHC) on bone and muscle health in elderly obese subjects

Obesity is an increasing, global public health issue. Patients with obesity are at major risk for developing a range of comorbid conditions, including cardiovascular disease (CVD), gastrointestinal disorders, type 2 diabetes (T2D), respiratory problems, and psychological issues, which may significantly affect their daily lives as well as increasing mortality risks. Obesity and aging have additive effects on chronic inflammation and thus may further contribute to the age-related obesity complications, including enhanced osteoclastic activity and sarcopenia. In the last years, accumulating evidences suggest that obesity increased risk of fracture. Fractures in obese women are associated with greater morbidity and postoperative complications. A key role in these processes is played by the WNT signaling, which expression enhances osteoblastogenesis, myogenesis, while prevents adipogenesis. With aging, however, WNT expression is downregulated favoring adipogenic pathway and inflammatory state. New evidence supports also a link between Endocannabinoid system (ECS) dysregulation, and WNT signaling on determining inflammation associated with obesity. It has been shown that a fiber enriched high carbohydrate diet (FEHC) improved metabolic outcomes and inflammation parameters compared to a standard diet. Furthermore, this diet approach modulated gut dysbiosis counteracting the increase of possible pro-inflammatory species. However, previous data show that standard weight loss intervention increased bone resorption and in turn bone and muscle loss. The primary aim of this study was to test FEHC diet in elderly obese subjects on improving obesity-related inflammation on bone, muscle and adipose tissue, through a positive modulation of WNT and ECS pathway. Elderly subjects with obesity were enrolled prior total hip arthroplasty. Prior to procedure they were randomized to a 3-month diet intervention, according to 1) Control group; 2) FEHC diet group. After the procedure, subjects were followed according to randomization for other 6 months with an isocaloric dietary regimen, different in macronutrients composition. Inflammation parameters was assessed at baseline and after three months in serum; WNT and ECS pathways were assessed femoral bone, adipose tissue and skeletal muscle after surgery.