When overweight mice eat fewer calories, their blood sugar control gets better — but if their diet is very low in carbs, their blood sugar doesn’t improve as much as if they ate more carbs.

When overweight mice eat significantly less food, they lose body fat no matter if their diet is low in carbs, low in fat, or high in protein — the key is eating fewer calories overall.

Older male rats that had eaten a fattening diet did better with blood sugar and gained less weight when they ate 30% fewer calories for five weeks — showing that cutting calories can still help, even after bad eating habits.

When overweight mice lose weight by eating less, their cholesterol levels go down — no matter what kind of food they eat — because the drop in cholesterol is tied to how much weight they lost.

When overweight mice eat fewer calories, only those on a low-carb, high-fat diet see a big drop in blood fats called triglycerides — other diets don’t have the same effect.

In rats, eating a high-fat, low-carb diet makes their bodies worse at handling sugar—even when calories are the same or higher—but doesn’t change how sensitive they are to insulin. This suggests the sugar problem might not be caused by insulin issues in these animals.