Obesity in Your 20s and 30s May Increase Cancer Risk Later in Life

A major study of 6.3 million South Korean adults ages 20–39 found that obesity in young adulthood significantly increases cancer risk before midlife, with risk rising progressively from 1.84% at moderate weight to 2.62% at severe obesity. Abdominal obesity (high waist circumference) showed similar elevated risk even in moderately weighted individuals, and certain cancers—thyroid, endometrial, ovarian, colorectal, kidney, liver, and pancreatic—showed the strongest associations.