Three Diets, the Same 10 Percent Weight Loss, and Only One Cut Liver Fat by Two Thirds

Two people can lose the same amount of weight and end up with meaningfully different livers. That is the finding from a controlled feeding trial in which adults with obesity, prediabetes, and fatty liver disease were assigned to one of three diets and brought to the same weight target.

All three groups shed about 10 percent of their starting weight over roughly five months, and all three improved insulin sensitivity in muscle by about 50 percent. Liver fat was where they diverged. It fell by an average of 67 percent in the ketogenic group, compared with 45 percent in both the Mediterranean and low-fat plant-forward groups, according to WashU Medicine, which led the trial. About half the ketogenic group no longer met criteria for prediabetes by the end, versus 29 percent on the Mediterranean diet and 7 percent on the plant-forward plan.