WebMD Feature from “Prevention” Magazine
By Julie Upton, RD

Learn the truth behind the folklore and use it to your weight loss advantage.

Google the word metabolism and you’ll find nearly 45 million results–advice on how to “speed-up,” “ignite,” “kick-start,” and “boost” your body’s fat-burning capacity. Truth is, there are probably more myths about metabolism than there are about the Loch Ness Monster and Bigfoot combined. The reality: Your body does burn 2 to 5% fewer calories with each decade after age 40, and women tend to put on about a pound a year as a result, but these changes are not inevitable, says Matt Hickey, PhD, director of the Human Performance Clinical Research Lab at Colorado State University. Simple tweaks to your daily routine can up your calorie burn and compensate for the deficit, keeping you from succumbing to age-related weight gain. Take our quiz and learn the truth about harnessing your metabolism to keep off unwanted pounds.

Your body burns more calories digesting ice-cold beverages and foods (T/F)
True. But before you give yourself an ice-cream headache, there’s more. “The small difference in calories probably won’t make a significant dent in your diet,” explains Madelyn Fernstrom, PhD, CNS, founder and director of the UPMC Weight Management Center in Pittsburgh. On the bright side, different studies have suggested that five or six ice-cold glasses of water could help you burn about 10 extra calories a day–equaling about 1 pound of nearly effortless weight loss each year.

Tip Although the metabolism-boosting effects are small, it can’t hurt to pour no-cal drinks–water, tea, coffee–on the rocks to maximize your body’s calorie-burning potential.

Drinking the right amount of water can help you burn more calories (T/F)
True. All of your body’s chemical reactions, including your metabolism, depend on water. If you are dehydrated, you may be burning up to 2% fewer calories, according to researchers at the University of Utah who monitored the metabolic rates of 10 adults as they drank varying amounts of water per day. In the study, those who drank either eight or twelve 8-ounce glasses of water a day had higher metabolic rates than those who had four.

Tip If your urine is darker than light straw in color, you may not be drinking enough fluid. Try sipping one glass before each meal and snack to stay hydrated.

Dieting drops your resting metabolic rate, making it harder to keep weight off (T/F)
True. For every pound you lose, your resting metabolism drops by about 2 to 10 calories a day. Lose 10 pounds, and you now have to eat 20 to 100 fewer calories to maintain your trimmer physique, not factoring in exercise. However, you can prevent your metabolic rate from slipping while you get slim. One way is to lose fat but maintain muscle. You can do this by reducing calories and increasing aerobic and resistance exercise, says Hickey. Crash diets (fewer than 1,000 calories a day) may result in a higher percentage of muscle loss.

Tip Lose weight by cutting 250 calories a day and burning 250 calories per day through exercise. That will help you retain–or even gain–muscle while you lose a greater percentage of body fat.

Hot foods will fire up metabolism (T/F)
True. Capsaicin, the bioactive compound that makes chile peppers exude heat, can turn your metabolism up a notch while also enhancing satiety and reducing hunger. Studies show that eating about 1 tablespoon of chopped red or green chile pepper–which is equal to 30 mg of capsaicin–resulted in up to a temporary 23% boost in metabolism. In another study, 0.9 g of red pepper was given in capsule form or naturally in tomato juice before each meal. The researchers noted that the individuals reduced their total calorie intake by 10 or 16%, respectively, for 2 days after and still reported being full.

Tip Sprinkle red-pepper flakes onto pasta dishes and into chilis and stews; fresh chile peppers work well in salsas and add a fiery flavor to many other dishes.

Eating more protein will rev up your metabolism (T/F)
True. Protein provides a metabolic advantage compared with fat or carbohydrates because your body uses more energy to process it. This is known as the thermic effect of food (TEF). Studies show that you may burn up to twice as many calories digesting protein as carbohydrates. In a typical diet, 14% of calories come from protein. Double that (and reduce carbs to make up for the extra calories), and you can burn an additional 150 to 200 calories a day, explains Donald Layman, PhD, a professor of nutrition at the University of Illinois.

Tip To reap protein’s rewards, strive for between 10 and 20 g at each of your meals, says Hickey. Try an 8-ounce cup of low-fat plain yogurt with breakfast (about 13 g), a 1/2-cup serving of hummus with lunch (about 10 g), and a 3-ounce salmon fillet for dinner (about 17 g).

Eating a grapefruit before every meal speeds metabolism (T/F)
False. Grapefruit won’t work miracles for your metabolism, but it can help you lose weight. Half a grapefruit before meals helped individuals lose about 4 pounds in 12 weeks, according to a study published in the Journal of Medicinal Food. The reason: Its fiber and water fill you up on fewer calories, so you eat less at your next meal.

Tip Instead of soup or salad, try a juicy piece of fresh fruit–half a grapefruit, a tangerine–before your main course.

Lifting weights boosts your metabolism more than a cardio workout (T/F)
True. When you strength-train enough to add 3 pounds of muscle, you increase your calorie burn by 6 to 8%–meaning that you burn about 100 extra calories every day. Aerobic exercise, on the other hand, doesn’t significantly increase your body’s lean muscle mass. “The best way to gain muscle mass is to do resistance training,” notes Ryan D. Andrews, RD, a certified strength-training specialist in Colorado.

Tip “You want to focus on exercises that recruit the largest muscles and use two-part movements, because they will help you build more lean mass,” Andrews says. His favorites include squats, push-ups, and any exercise that combines upper- and lower-body movements. For a metabolism-boosting strength-training workout, visit

Celery is a “negative calorie food” because digesting it uses up more calories than it provides (T/F)
False. The thermic effect of food does cause your body to burn up calories as it processes meals, snacks, and beverages. But this process accounts for anywhere from 0 to 30% of the calories you eat (protein, for example, takes more calories to digest than fat or carbohydrates; see p. 86). A medium-size rib of celery has only about 6 calories; its TEF is approximately half a calorie. In reality, “negative calorie foods” are nothing more than wishful thinking.

Tip Include celery as a low-cal but filling addition to salads, stir-fries, and soups; you can’t depend on it to magically melt away your trouble spots. But it is healthful: Celery has phthalides, compounds that can help reduce blood pressure.

Tea revs your natural calorie burn (T/F)
True. Catechins found in green and oolong teas can boost the body’s fat-burning fire. One study of Japanese women compared the effects of drinking green tea, oolong tea, or water on various days. Just one large cup of oolong tea increased calorie burning by up to 10%, a boost that peaked 1 1/2 hours later. Green tea raised metabolism by 4% for 1 1/2 hours. Other studies show that drinking two to four cups of green or oolong daily (about 375 to 675 mg of catechins) may translate into an extra 50 calories burned each day–about 5 pounds’ worth in a year.

Tip Try a cup of green or oolong tea in place of your morning coffee for a dose of caffeine that will wake up your metabolism as well. Instead of milk or sweetener, add a squeeze of lemon, which may help your body absorb more catechins.

PMS cravings are related to the boost in metabolism before your period (T/F)
True. If there is a silver lining to PMS, it’s that our resting metabolic rate may increase during the part of the menstrual cycle known as the luteal phase (the day after ovulation to the first day of your period). The metabolic boost we get from being “hormonal” can equal as much as 300 calories a day–which is why our appetite increases during this phase.

Tip Keep a journal of what you eat the week before and the weeks after your period. Try to maintain your eating pattern over the course of the month so that you can take advantage of this hormone-driven calorie burn. If you give in to cravings, make sure that you keep portions in check.

If you have limited time, exercise at a higher intensity for a metabolic afterburn. (T/F)
True. People who exercise at very high intensities experience a postexercise boost in resting metabolic rate that is larger and lasts longer compared with those who work out at a low or moderate level. Up the effort of your workout and you can expect to burn at least 10% of the total calories used during the workout in the hour or so after exercising. So, if you do a combo of walking and jogging for 4 miles (about 400 calories) instead of just walking, you may burn an extra 40 calories in the next few hours.

Tip Infuse your workout with bursts of speed. Gradually work your way up to 2-minute intervals, 3 days a week.