In healthy adults who lose 5–7 kilograms over two years, insulin sensitivity improves, the IGF-1 to IGFBP-1 ratio decreases, and biological age declines by 2–3 years. If weight is regained by more...
Mechanism
Synthesis from 1 study
Losing weight and keeping it off tells your cells to slow down aging by reducing insulin and a growth hormone called IGF-1, which lets your body focus on repair instead of growth — this is shown in the CALERIE-2 trial (10.2337/dc25-1911). But if you gain the weight back, your body starts producing...
Most probable mechanism
When people lose 5–7 kg and keep it off, their bodies produce less insulin and a hormone called IGF-1 becomes less active because another protein, IGFBP-1, binds to it and blocks its effects. This tells cells to slow down growth and repair processes, which makes them age more slowly. But if they gain back more than 5% of the weight, fat tissue grows again, insulin and IGF-1 levels rise, and the protective effects vanish — all because the body’s energy-sensing system gets turned back on. This is shown in the CALERIE-2 trial (10.2337/dc25-1911).
Caloric restriction reduces adipose tissue mass, lowering leptin secretion and insulin production from pancreatic β-cells — 10.2337/dc25-1911
Reduced insulin signaling downregulates the PI3K/AKT/mTOR nutrient-sensing pathway, suppressing cellular growth and promoting maintenance processes like autophagy — 10.2337/dc25-1911
Lower insulin levels increase hepatic production of IGFBP-1, reducing free IGF-1 bioavailability and further inhibiting mTOR activation — 10.2337/dc25-1911
Sustained suppression of insulin/IGF-1/mTOR signaling reduces metabolic rate of aging processes, leading to a measurable decrease in biological age — 10.2337/dc25-1911
Weight regain restores adipose tissue mass, triggering hyperleptinemia and leptin resistance, which promotes hyperphagia and re-establishes positive energy balance — 10.2337/dc25-1911
Restored nutrient availability reactivates insulin secretion and IGF-1 bioavailability, reactivating mTOR signaling and suppressing autophagy and DNA repair — 10.2337/dc25-1911
Reactivation of insulin/IGF-1/mTOR signaling reverses improvements in insulin sensitivity and biological age, erasing the benefits of prior weight loss — 10.2337/dc25-1911
Evidence from Studies
Supporting (1)
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