Giving mice a high-fat diet plus L-carnitine seems to protect their livers — the more L-carnitine they get, the better the results, with less fat and damage in the liver.

In mice with fatty liver caused by a bad diet, taking a certain amount of L-carnitine seems to fix unhealthy fat levels in the liver, which might help protect the liver by changing how fats are processed.

In mice with fatty liver caused by a bad diet, taking a supplement called L-carnitine seems to change how their liver handles fats in a way that might help protect them.

In mice eating a bad diet, taking a supplement called L-carnitine seems to calm liver inflammation and might help protect against fatty liver disease.

In mice on a bad diet, certain fat types in the liver change when they get fatty liver disease — but giving them a supplement called L-carnitine helps reverse those changes, so those fats might be useful clues to track the disease and how well treatment works.

Even when rats eat fewer calories, a keto-like diet can still cause liver problems — like making too much sugar and messing up how the body uses protein — so the weight loss might not be worth the harm.