There’s a reason everyone harps on about protein: Not only does it help keep you full, but it’s also responsible for repairing the tiny tears caused by strength training in your muscles. This helps them grow bigger and stronger, nudging out body fat in the process. As a general rule of thumb, aim to get at least 70 grams of protein throughout the day, says Dr. Cheskin. (These high-protein foods can help you reach that goal.)
Too little sleep or too much sleep can throw your stress and regulatory hormones out of whack, and may lead to weight gain. A single night of sleep deprivation can increase levels of ghrelin (a hormone that promotes hunger), making you more likely to overeat the next day. Reduced sleep may also lead to fatigue during the day (duh) and less physical activity, which may be another reason why people who regularly don't get enough sleep tend to gain weight.
If you’ve got weight to lose and you want it gone fast, try swapping out your usual proteins in favor of fish. Not only is fish lower in calories than an equivalent amount of beef or chicken, a study published in Obesity reveals study subjects who added omega-3 fatty acids, like those found in fish, to their diets shed more weight and had an easier time keeping it off than those who skipped them.
Why does HIIT training work better than conventional cardio for fat loss? When you do cardio at the same pace, your body adjusts itself to the workload and tries to conserve calories. (After all, your body doesn't know how long or hard you plan to work out.) Interval training forces your body to burn more calories -- and tap into fat stores -- because it has no choice. Science says so: One study at Laval University found people who performed HIIT cardio lost nine times more fat than people who performed moderate cardio at a consistent speed.
Here's something else most people probably don't know: Fidgeting is good for you. It's considered a nonexercise physical activity, and it's an important way to burn energy. You get more health benefits if, in addition to exercising, you are a more fidgety, more active person the rest of the day. This means gesturing while you're talking, tapping your foot, just moving around.