The Genetic Paradox of Longevity: What's Behind the 50% Rule? Research has long suggested that longevity is largely determined by lifestyle choices, such as diet and exercise.
However, recent findings from Uri Alon's team at the Weizmann Institute of Science in Israel have challenged this assumption.
By adjusting their methodology to account for deaths caused by external factors rather than diseases of aging, they've discovered that genetics play a far more significant role in determining lifespan – around 50%.