Myths vs facts: Insulin and longevity

A common myth is that insulin is inherently harmful and that lowering it at all costs extends lifespan. The reality is more nuanced: while chronically high insulin (hyperinsulinemia) is linked to metabolic disease and accelerated aging, insulin is essential for survival. The key factor is insulin sensitivity – how effectively cells respond to the hormone. Lifestyle interventions like caloric restriction and intermittent fasting improve sensitivity and activate longevity pathways (e.g., mTOR inhibition, autophagy). Genetic variants (e.g., TCF7L2) have small effects and are not predictive on their own. Blood markers (fasting insulin, HOMA-IR) are more actionable. Marketing often overstates the role of single genes. Evidence is moderate: epidemiological and mechanistic studies support the link, but human longevity trials are lacking. Do not alter diet or medication without medical supervision.