Context Insulin resistance is an adverse health outcome that accompanies obesity. Fat mass is negatively associated with the bone mass after adjustment for confounders. Insulin resistance might be an intermediary in this relationship. Objective To determine whether insulin resistance is an intermediary in the relationship between adiposity and bone mass in adolescents. Design Cross-sectional secondary analysis of baseline data from a previous randomized trial. Setting University research facility. Participants A total of 240 adolescents (68% female), aged 7 to 15 years. Main Outcome Measures Using dual energy x-ray absorptiometry, bone mineral content (BMC), areal bone mineral density, lean mass, and fat mass were measured. Skeletal sites of interest included the total body and lumbar spine (LS). Waist circumference was measured using an anthropometric tape measure. Insulin and glucose were measured in fasting sera, and the homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. Path analysis was performed to determine whether the relationship between adiposity and bone was mediated through insulin resistance. Results Fat mass (r = 0.467; P < 0.001) and waist circumference (r = 0.487; P < 0.001) correlated positively with HOMA-IR. Controlling for race, sex, maturation, lean mass, and height, fat mass, waist circumference, and HOMA-IR were negatively associated with LS BMC and total body areal bone mineral density (P < 0.05 for all). Additionally, path models for fat mass (95% CI, −5.893 to −0.956) and waist circumference (95% CI, −15.473 to −2.124) showed a negative relationship with LS BMC via HOMA-IR. Conclusions These results support an intermediary role of insulin resistance in the relationship between adiposity and LS bone mass.

Weight loss is a major focus of research and public health efforts. Time-restricted eating (TRE) is shown to be effective for weight loss, but the impact on bone is unclear. Short-term TRE studies show no effect on bone mineral density (BMD), but no study has measured bone turnover markers. This secondary analysis examined the effect of 12 weeks of TRE vs. unrestricted eating on bone turnover and BMD. Overweight and obese adults aged 18–65 y (n = 20) were randomized to TRE (ad libitum 8-h eating window) or non-TRE. Serum N-terminal propeptide of type I collagen (P1NP), cross-linked N-telopeptide of type I collagen (NTX), and parathyroid hormone (PTH) levels were measured and dual-energy X-ray absorptiometry (DXA) scans were taken pre- and post-intervention. In both groups, P1NP decreased significantly (p = 0.04) but trended to a greater decrease in the non-TRE group (p = 0.07). The treatment time interaction for bone mineral content (BMC) was significant (p = 0.02), such that BMC increased in the TRE group and decreased in the non-TRE group. Change in P1NP was inversely correlated with change in weight (p = 0.04) overall, but not within each group. These findings suggest that TRE does not adversely affect bone over a moderate timeframe. Further research should examine the long-term effects of TRE on bone.

The rising incidence of cardiometabolic diseases and chronic kidney disease (CKD) is a leading public health problem in East Asia. Diet is an important modifiable risk factor; thus, adopting a healthy diet such as the Dietary Approaches to Stop Hypertension (DASH) diet may help combat these chronic diseases. The DASH diet was originally developed in a U.S. population, and East Asia is demographically and culturally different from the U.S. Therefore, it is important to examine the evidence regarding the DASH diet and chronic disease in this unique population. This narrative review summarizes the evidence on the DASH diet and cardiometabolic health and CKD in East Asia. Culturally-modified DASH diets have been developed in some East Asian countries. Studies suggest the DASH diet is effective at lowering blood pressure in this population, though the long-term benefits remain unclear. Evidence also suggests the DASH diet may reduce the risk of type 2 diabetes and metabolic syndrome. Further research indicates the DASH diet and its components may reduce CKD risk. However, recommending the DASH diet in those who already have CKD is controversial, as it conflicts with current CKD dietary guidelines, especially in advanced CKD. Notably, current intakes in the general population differ from the DASH dietary pattern, suggesting public health efforts would be needed to encourage adoption of the DASH diet.