When overweight people eat fewer calories and get regular coaching, it doesn’t matter much if their diet is high in fat, protein, or carbs—they lose about the same amount of weight no matter what.

If you're overweight and eat fewer carbs instead of less fat for four weeks, you might lose more body fat—even if you lose the same amount of total weight as someone on a low-fat diet.

If you're overweight and eat fewer carbs instead of less fat for four weeks—without counting calories—you might lose about 8 pounds more than someone on a low-fat diet, and it might be because you're losing more body fat.

If you're overweight and eat less fat for four weeks, you might lose more muscle than fat compared to someone who eats fewer carbs — even if both diets help you lose weight.

The more often overweight people attend weight-loss counseling sessions, the more weight they lose—even if they’re on different diets—suggesting support matters more than what you eat.

When people are taught how to eat healthier, those on a low-fat diet end up eating about half carbs and a third fat, while those on a low-carb diet eat about a third carbs and almost half fat — and both groups stick to their plans similarly.