Your body digests protein more slowly than fat or carbs, so you feel full longer (this is especially true when you have it for breakfast). Plus, it may also give your metabolism a bump. In a process called thermogenesis, your body uses about 10% of its calorie intake for digestion. So, because it takes longer to burn protein than carbs or fat, your body expends more energy absorbing the nutrients in a high-protein diet. Another bonus: One recent study from Purdue University found that diets higher in protein may help preserve lean body mass, which is the best fat-burner of all.
Most of your resting metabolism is taken up by your organs—brain, heart, liver, etc. But the biggest factor affecting your metabolism that you can control is your ratio of body fat to lean muscle mass. "Muscle burns more calories than fat tissue, because muscle requires more energy to maintain," says Harold Gibbons, New York State Director of the National Strength and Conditioning Association. "The more fat you have, the slower your metabolism will be."
Stephen Colbert’s doing great, but now it’s time to DVR him and start getting to bed earlier. A study in Finland looked at sets of identical twins and discovered that in each set of siblings, the twin who slept less had more visceral fat. If you do nothing else differently, just getting an extra half hour of shuteye will make all the difference. If you’re chronically sleep deprived, don’t be surprised if you gain a few pounds without eating a morsel of extra food. “A lack of sleep can cause several metabolic problems,” says nutritionist Seth Santoro. “It can cause you to burn fewer calories, lack appetite control and experience an increase in cortisol levels, which stores fat.” Lack of sufficient sleep—under the recommended seven to nine hours a night for most adults—also leads to impaired glucose tolerance, a.k.a. your body’s ability to utilize sugar for fuel. “We all have those less-than-adequate nights of sleep,” says nutritionist Lisa Jubilee. “But if it’s a regular thing, you’re better off lengthening your night’s sleep than working out, if fat loss or weight maintenance is your goal.”
Not only is vinegar great on salad, it’s also shown to “switch on” genes that release proteins that break down fat. In a study of 175 overweight Japanese men and women published in Bioscience, Biotechnology, and Biochemistry, researchers found that participants who drank one or two tablespoons of apple cider vinegar daily for 12 weeks significantly lowered their body weight, BMI, visceral fat, and waist circumference.
The easiest 350 calories you'll ever burn: Exercise is obviously important, but regular daily activity known as "NEAT" (nonexercise activity thermogenesis) is equally essential for a healthy metabolism. Small movements such as stretching your legs, taking the stairs, even just standing to talk on the phone increases your energy expenditure and can add up to an extra 350 calories burned a day.