Two out of three adults with obesity have non-alcoholic fatty liver disease (NAFLD), which boosts the risk of type 2 diabetes.

Scientists randomly assigned 80 adults with NAFLD to alternate-day fasting (eating only 600 calories on their fast days), aerobic exercise (five one-hour sessions per week), both, or no intervention (control).

After three months, liver fat fell 5 percent in the fasting + exercise group, 2 percent in the fasting-only group, 1 percent in the exercise-only group, and 0.2 percent in the control group. Insulin resistance also fell more in the fasting + exercise group than in the control group, with the other groups in between.

What to do

Got NAFLD? Try alternate-day fasting—or any diet that leads to weight loss—plus exercise. Replacing saturated fats (in meat, dairy, etc.) with unsaturated fats (in oils, nuts, etc.) can also lower liver fat.