13 Habits Linked to a Long Life (Backed by Science) Many people think that life expectancy is largely determined by genetics. However, genes play a much smaller role than originally believed. It turns out that environmental factors like diet and lifestyle are key. Here are 13 habits linked to a long life. Share on Pinterest 1. Avoid overeating The link between calorie intake and longevity currently generates a lot of interest. Animal studies suggest that a 10–50% reduction in normal calorie intake may increase maximum lifespan ( 1 Trusted Source ). Studies of human populations renowned for longevity also observe links between low calorie intake, an extended lifespan, and a lower likelihood of disease ( 2 Trusted Source , 3 Trusted Source , 4 Trusted Source ). What’s more, calorie restriction may help reduce excess body weight and belly fat , both of which are associated with shorter lifespans ( 5 Trusted Source , 6 Trusted Source , ...