Endocrine Changes of Aging

Aging changes endocrine signalling gradually. Growth-hormone and insulin-like growth factor-1 activity decline, as does sex-steroid production. The result is a shift in body composition: less lean muscle, more fat mass, reduced bone density, and less physical reserve during illness or immobility. Muscle is a major site of glucose disposal. As muscle mass falls and fat mass rises, insulin-mediated glucose uptake becomes less efficient. Post-meal glucose elevations may therefore become more apparent with age, especially when inactivity, acute illness, or medications add further metabolic stress. These changes help explain why an older adult may lose strength, develop frailty, or become more vulnerable to osteoporosis. They do not make marked fatigue, rapid weight change, recurrent falls, confusion, or a new fracture “normal.” Aging lowers reserve; disease still requires assessment. The clinical task is to separate a gradual age-related change from a reversible endocrine problem. An older adult who is slowly losing muscle after prolonged inactivity needs a different response than one whose weakness began over weeks with weight loss, tachycardia, polyuria, or medication changes.