It’s something entirely different and it has much to do with your body functioning. The main sign you should change your diet lies in fantasizing about French fries, burgers and other “guilty pressures” that reveal your body isn’t getting the nutrients it needs.
If you cut the foods that are high in fat and switch to a high protein and carb diet you might end up with cravings that can ruin your diet, but most importantly those cravings tell you your body is missing something.
The best way to keep cravings at bay is to have a balanced diet that will satisfy your body’s needs for all the nutrients. If, however, you need to cut back on the fat, add healthy fat to your meals, such as olive or avocado oil, or nuts and seeds. You’ll still be losing weight without putting yourself through the agony of altogether eliminating the foods you like.