Read on for some medically proven moves that'll make it happen - and help you drop some pounds. By Hallie Levine, REDBOOK.
Stock up on green tea
Green tea isn't known only for its cancer-fighting benefits: It may help boost your metabolism, too. People who took green-tea extract three times a day saw their metabolic rate increase by about 4 percent, according to a study published in the American Journal of Clinical Nutrition. (Translation: You could burn an extra 60 calories a day, which equals about six pounds a year!) It may be because green tea contains catechins, which increase levels of the metabolism-speeding brain chemical norepinephrine, says Joy Bauer, a New York City nutritionist and author of Cooking with Joy.
Weight training is the ultimate way to burn calories fast. "A pound of muscle burns up to nine times the calories of a pound of fat," explains Richard Cotton, M.A., chief exercise physiologist for myexerciseplan.com. Weight training increases your resting metabolic rate, which is the number of calories you burn while sitting on your butt. What's more, it gives your metabolism an added boost after you exercise: It remains in overdrive for up to two hours after the last bench press, according to a study published in Medicine & Science in Sports & Exercise. Strapped for time? Try these quick moves: squats, bench step-ups, lunges, push-ups, pull-ups and crunches. In a pinch, just do single sets of 10 for each exercise - you'll get optimal results for the time invested.
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Yeah, we just told you to pump iron, but you also need to eat it. "If you don't have enough of this mineral, your body can't get enough oxygen to your cells, which slows down your metabolism," explains Samantha Heller, R.D., a nutritionist at the New York University Medical Center. Most multivitamins contain around 18 mg (the RDA for adults); you can also get your fill by eating three to four daily servings of foods rich in iron, such as lean red meat, chicken, fortified cereal and soy nuts. If you are feeling symptoms such as fatigue and weakness, ask your doctor to test you for anemia (it's a simple blood test) at your next physical.
Order water - and ask for a refill
A German study found that when you drink 17 ounces of water (about two glasses) within a certain time frame, your metabolic rate shoots up by about 30 percent. Using these results, they estimate that by increasing your current water intake by 1.5 liters a day, a person would burn an extra 17,400 calories a year, resulting in about a five-pound weight loss.
Get your thyroid checked
Suspect you have a sluggish metabolism? You might have hypothyroidism, or an underactive thyroid gland, which afflicts about 25 percent of American women - many of whom don't know they have the condition, according to the American Association of Clinical Endocrinologists. "The thyroid gland controls your body's metabolism, so one of the first signs that it may be off is an inability to lose weight," explains Pamela Peeke, M.D., professor of medicine at the University of Maryland and author of Fight Fat After Forty. Your doctor can determine if you're suffering from hypothyroidism by running a blood test. If you do have an underactive thyroid, you'll be treated with a synthetic thyroid supplement, which you will need to take for the rest of your life (it will return your metabolism to normal, so it should be easier to lose weight).
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Want to keep your favorite meals from going straight to your hips (thighs, belly)? Wash them down with water, not wine. Alcohol slows your metabolism by depressing the central nervous system. A British study found that when alcohol was added to a high-fat, high-calorie meal, less dietary fat was burned off and more was stored as body fat.
Rev up workouts
Interval training - in which you add bursts of high-intensity moves into your workout - is a surefire metabolism booster, says Glenn Gaesser, Ph.D., director of the Kinesiology Program at the University of Virginia and author of The Spark. Researchers at Laval University in Quebec found that high-intensity interval training burns more fat than regular, consistent aerobic exercise. If you usually jog at a 10-minute-mile pace, for example, add a 30-second sprint every five minutes. Or add a one-minute incline to your treadmill workout every five minutes. "Even if you just have 10 minutes for a quick workout, you can walk at a normal pace and then add in a 30-second bout of speed-walking every three minutes," recommends Gaesser.
Do more dairy
Women who ate low-fat dairy products, such as nonfat yogurt and low-fat cheese, three to four times a day lost 70 percent more fat than low-dairy dieters, according to a study published in the journal Obesity Research. "Calcium serves as a switch that tells your body to burn excess fat faster," explains study author Michael Zemel, M.D., director of the Nutrition Institute at the University of Tennessee in Knoxville. Sorry, but you won't reap the same benefits from calcium-fortified O.J. Research shows that you get the best results from dairy products themselves, not fortified foods. Aim for 1,200 mg, which includes about three servings of dairy a day.
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Take up a new sport
Are you like Old Faithful when it comes to your morning walk or evening jog? Know this: The more you do an activity, the more your body adapts to it, so you burn fewer calories. If you want to light a fire under your metabolism, consider cross-training. For example, if you normally walk, try biking instead. "Since you're not used to working all those different muscles, it's a more intense workout, which can translate into a greater metabolic after-burn because your body is working harder to recover and get oxygen to all your tissues," says Carol Espel, M.S., an exercise physiologist for Equinox Fitness Clubs in New York City.
Break out the lemon wedges: Regular fish eaters tend to have lower levels of the hormone leptin - good because high levels of leptin have been linked to low metabolism and obesity, says Louis Aronne, M.D., an obesity specialist at the New York Presbyterian Weill Cornell Medical Center. Try to consume three to four servings of a fatty fish, such as salmon, tuna or mackerel, each week.
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