Multiple studies have shown reduced-carbohydrate diets drive reductions in liver fat content in subjects with nonalcoholic fatty liver disease (NAFLD). Earlier studies, however, used diets restricted in both carbohydrates and total calories; they therefore could not distinguish between the effects of carbohydrate restriction, calorie restriction, and weight loss on changes in liver fat. This 2018 trial was designed to assess the specific effect of carbohydrate restriction. It demonstrated severe carb restriction leads to rapid and dramatic improvements in liver fat content in subjects with NAFLD, reducing the amount of fat in the subjects’ livers by half in 14 days without any deliberate calorie restriction.