Bone-derived osteokines regulate systemic glucose and energy metabolism beyond structural roles

Bone remodeling releases osteocalcin, FGF23 and sclerostin that act as circulating hormones. Human studies measuring undercarboxylated osteocalcin show inverse associations with fasting glucose (beta -0.8 mg/dL per SD) and HOMA-IR after adjustment for BMI and physical activity. These signals integrate mechanical loading, parathyroid hormone and estrogen status to coordinate mineral flux with whole-body fuel use.

Longitudinal data link accelerated bone turnover after menopause to 18-22% higher incidence of type 2 diabetes over 10 years, independent of BMD loss. Astronaut studies and bed-rest trials demonstrate parallel declines in bone formation markers and insulin sensitivity within weeks, reversible by mechanical reloading. Such patterns reveal bone as an active endocrine tissue rather than passive reservoir.

Current evidence remains largely observational; few RCTs have tested osteokine-targeted interventions on metabolic endpoints. Next required studies are placebo-controlled trials of osteocalcin analogs or sclerostin inhibitors with primary outcomes of HbA1c change and cardiovascular events at 2-year follow-up.

Funding sources in cited cohorts include NIH and European Commission grants without reported industry conflicts for primary analyses.