Visceral fat is fat stored deep in the abdomen around internal organs like the liver, pancreas, and intestines. Unlike subcutaneous fat (under the skin), visceral fat is metabolically active and releases inflammatory compounds that increase risk of heart disease, type 2 diabetes, and certain cancers.

A waist circumference over 40 inches (men) or 35 inches (women) suggests elevated visceral fat. Waist-to-height ratio above 0.5 is another red flag. Even people with normal BMI can have dangerous levels of visceral fat, sometimes called 'skinny fat.'

Visceral fat responds well to aerobic exercise (30-60 minutes of moderate cardio most days), reduced refined sugar and alcohol intake, stress management, and adequate sleep (7-9 hours). Spot reduction is not possible — overall fat loss through diet and exercise reduces visceral fat.