When rats eat a diet high in fat and low in carbs, their livers start making more sugar from lactate but get worse at breaking down an amino acid called alanine — especially if they're also eating fewer calories.

In rats, eating a diet high in fat and low in carbs changes how the liver handles certain fuels — it makes more sugar from lactate but gets worse at using alanine, especially when fewer calories are eaten.

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.

Eating fewer carbs might make your liver produce more sugar, and some scientists think this could put extra strain on your liver.

Even when rats eat fewer calories, a keto-like diet can still cause unhealthy changes in the liver, like making too much sugar and having trouble breaking down proteins.

Your liver makes its own sugar when you don’t eat carbs for a long time, and this process doesn’t hurt your liver or cause damage.