When attempting to lose body fat, insulin control is crucial. The total amount of insulin released by the body isn't related to just how many carbohydrates you eat but how fast those carbs are digested. Refined carbs digest quickly, raising insulin levels substantially, which is why you should avoid them. But if you do happen to eat, say, a bowl of cold cereal (typically a fast-digesting carb), you can still take measures to ensure those carbs digest more slowly. This will cause less insulin to be released and therefore have less of an impact on your ability to burn fat.
You don’t have to nix all carbs, just make sure you’re eating the right ones. A recent study published in Plant Foods and Human Nutrition found that after 12 weeks, men who ate only whole grains lost about an inch and a half off of their belly, while those who ate only refined grains didn’t lose any. Toss the white bread and pasta and stock up on complex carbs instead.
This may explain why the fat-burning effects of eating more protein were confirmed in a study published in the American Journal of Physiology. One group was fed a high-protein diet (just over 1 gram per pound of body weight per day) while the second group consumed an amount closer to the lower recommendation of the RDA (recommended dietary allowance). The group eating the higher-protein diet burned the most fat.