What's Your Weight Loss IQ?

You vowed to hit the treadmill and clear your fridge of holiday leftovers as soon as the ball dropped — but are you sabotaging your New Year's resolution to lose weight? Take our weight-loss IQ quiz to see if your "healthy" habits are actually hurting your waist size.

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What's Your Weight Loss IQ?

1. True or False: You can save calories by having your cereal without milk.

CORRECT ANSWER: False. A Weight Watchers study showed that people who ate cereal right out of the box as a snack tended to munch on way too much of it in a day. Even healthy, high-fiber cereals can up the day's calorie count and halt people's weight loss. Eat cereal only with milk. This combination also decreases the meal's "calorie density" — an ounce of cereal with milk (skim, of course) has fewer calories than an ounce of cereal alone, so you'll take in fewer calories but still feel just as satisfied.

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What's Your Weight Loss IQ?

2. According to the Health and Human Services Department, how long should you be vigorously exercising every week to stay healthy?

A. 45 minutes
B. 1.5 hours
C. 2.5 hours
D. 5 hours

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What's Your Weight Loss IQ?

CORRECT ANSWER: C, 2.5 hours. Yet a quarter of U.S. adults aren't active at all in their leisure time, government research concludes. More than half don't get enough of the kind of physical activity that actually helps health — walking fast enough to raise your heart rate, not just meandering, for instance.

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What's Your Weight Loss IQ?

3. True or False: You should pick diet soda over regular to lose weight.

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What's Your Weight Loss IQ?

CORRECT ANSWER: False. Quench your thirst with water instead. People who quaff sugar-free soft drinks are 41 percent more likely to gain weight than people who drink regular sodas, according to a University of Texas study. Experts speculate the body isn't fooled by zero-calorie sweets and that it actually searches for sugary foods to make up for calories it expected to get from a faux-sugar beverage.

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What's Your Weight Loss IQ?

4. At what point in your workout should you do cardio?

A. First
B. Last
C. Your entire workout should be cardio.
D. It doesn't matter.

CORRECT ANSWER: B, Last. Strength-train before doing any cardiovascular work, says Ken Fitzgerald, owner of Lift Gym in New York. Why? It takes the body about 15 minutes to warm up and start burning fat. So, a 30-minute bike ride is really only burning fat for the last 15 minutes of your workout. But, if you lift weights first, your body is warmed up by the time you hit the bike, and you'll burn fat throughout the entire ride.

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5. True or False: Fat-free dressing is the healthiest.

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What's Your Weight Loss IQ?

CORRECT ANSWER: False. You do save on calories when you take out the fat, but many fat-free dressings are loaded with sugar, and offer zero nutrition. In one study, people eating full-fat salad dressing absorbed twice the nutrients of those using reduced-fat dressing. Fat-free dressing allowed for virtually no absorption of these good guys.

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6. A study found that people can eat up to what amount less to lose weight without triggering feelings of hunger?

A. 5%
B. 10%
C. 20%
D. 40%

CORRECT ANSWER: C, 20%. Brian Wansink, Ph.D., author of Mindless Eating, found that most people can eat 20 percent less without triggering feelings of hunger. Dish up 20 percent less pasta on your plate and replace it with 20 percent more vegetables.

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7. True or False: Breathing through your nose instead of your mouth during a workout burns more calories.

CORRECT ANSWER: True. Inhaling and exhaling through your nose, rather than your mouth, helps stabilize your heart rate and increase your endurance. The result? You work out longer and burn more calories. But don't get discouraged if it feels unnatural at first — it takes about six to eight workouts to perfect.

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What's Your Weight Loss IQ?

8. If you're just starting to work out, what's the best way for you to burn fat?

A. Work out as hard as you can, for as long as you can.
B. Start slow with a short workout and increase your exercise time over a few weeks.
C. Do a short workout in the morning and a short workout in the evening.
D. Do interval training.

woman checking her heart rate during a workout

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What's Your Weight Loss IQ?

CORRECT ANSWER: D, interval training. Two minutes on the treadmill at, say, 7 mph, followed by two minutes at 5 mph, then back to 7 mph (and so on) for 20 to 45 minutes will whittle away pounds and build your endurance. Eventually, you'll be able to extend the high-intensity periods until your whole workout is done at top speed.

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9. True or False: Dieting can be bad for your health, even if you succeed in slimming down.

CORRECT ANSWER: True. When scientists observed nearly 3,000 overweight twins, they saw that those who had previously dieted were more likely to die during the 18 years of the study than those who simply maintained the same weight. Researchers suspect that yo-yo dieting places so much stress on your body that it can outweigh the benefits of slimming down.

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What's Your Weight Loss IQ?

10. How soon before a workout should you eat to improve your performance?

A. 30 minutes
B. An hour
C. 90 minutes
D. 2 hours

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What's Your Weight Loss IQ?

CORRECT ANSWER: C, 90 minutes. Eating a low-carbohydrate protein bar 90 minutes before you work out will enable you to exercise longer and harder (and burn more calories) than you normally would, says Steve Zim, author of Hot Point Fitness. However, that 90-minute mark is crucial. Eat any closer to your workout, and blood will rush to your stomach, actually diminishing your performance.

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