In a 16-year study at Harvard, scientists found that people who slept for 5 hours or less a night were 32 percent more likely to pack on major pounds than those who dozed a full 7 hours. Although "major" was defined as 33 pounds, the average increase was 2 pounds a year, a gain that's easy to miss from month to month. "Due to accumulating fatigue, those who get the least shuteye may also move around the least during the day," says study author Sanjay Patel, M.D.
Trouble hitting the sack? Here's How to Snooze Like a Baby--No Matter Your Age.
Warning: Your breakfast may be larger than it appears. Cornell University scientists found that people ate more cereal from bigger bowls than from smaller ones, even though they thought the opposite to be true. "It's called the size-contrast illusion," says researcher Brian Wansink, Ph.D. "Because food takes up a smaller percentage of space in larger dishes, it seems like you're eating less." Use a measuring cup to portion out your cereal; in a few days, you'll be able to eyeball servings accurately.
Plus: Lose fat faster, build bigger muscle, and last longer in bed!
An 11-minute workout can help you burn more fat all day long, say researchers from Southern Illinois University at Edwardsville. In the study, people who lifted weights for that duration three times a week increased their metabolic rate even as they slept. "The process of breaking down and repairing your muscles increases your metabolism," says study author Erik Kirk, Ph. D. What's more, the participants were able to fit their workouts into their schedules 96 percent of the time.
Transform your body into a fat-burning machine with these 5 Easy Ways to Rev Your Metabolism.
To take inches off your waist, work the muscles below your belt. In a new Syracuse University study, people burned more calories the day after they did lower-body resistance training than the day after they worked their upper body. "Leg muscles like your quads and glutes generally have more mass than the muscles in your chest and arms," says study author Kyle Hackney, Ph. D.(c). "Work more muscle, and your body uses more energy to repair and upgrade it later." The best approach? Hit every muscle each workout.
Need a plan? Try: The Incredible 82-Day Speed Shred.
A stressful job may make you fat, suggest Harvard researchers who followed 1,355 Americans for 9 years. They found that overweight men with little authority at work gained more weight than men with more authority did. Not being able to make decisions is linked to stress. Eating can be calming because it releases mood-improving endorphins, says study author Jason Block, M.D. The best stress-busting fat burner? Exercise.
Video: Just getting into yoga? Start with The Best Yoga Poses for Guys.
To drop weight, you need to cut back on certain foods--but not dairy. Milk and other dairy products can help dieters slim down and beef up, say Canadian researchers. Their study found that heavy people who exercised every day and followed a high-protein, high-dairy (and calorie-restricted) diet for 16 weeks lost about 10 pounds of fat and gained 1 1/2 pounds of muscle. (Those who ate less dairy and protein still lost weight, but they also lost muscle.) The reasons: Milk may help regulate appetite, and whey protein can activate muscle growth.
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Eating frequent, low-sugar desserts can help keep the weight off. Dieters in a Greek study who ate a low-sugar dessert four times a week lost 9 more pounds after 12 weeks than those who ate any dessert they wanted just once a week. (Search: Healthiest Desserts) Eating dessert more frequently can keep you from feeling deprived, the researchers say. But limit desserts to around 10 percent of your daily calories.
Want great desserts that won't tip the scale? Check out these 15 Dessert Swaps for Weight Loss.
A worldwide consensus has formed: Eating a diet that's low in carbs, not fats, is the best way to lose weight. In a recent United Arab Emirates study, people who followed a low-carb diet had lower body weights, insulin levels, and triglyceride levels than those who went with a low-fat diet. And a European study that tracked nearly 90,000 people for several years found that participants with a low fat intake had the same risk of being overweight as those who ate higher amounts of fat. Still, if you boost your fat intake, make sure you adjust your calories and physical activity accordingly.
Related: 12 Tasty Substitutions When Cutting Carbs
Turns out, soft drinks really are just empty calories. Penn State University researchers fed men lunch once a week for 6 weeks, along with either a 12 or 18-ounce regular soda, diet soda, or water. The result: The men ate the same amount of food no matter the size or type of beverage served. Which means they consumed far fewer total calories when they drank water or diet soda compared with the sugar-laden stuff. What's more, the participants' ratings of satiety and hunger were identical after each lunch, showing that the extra calories in the regular soda had no benefit.
Sugar doesn't just come in the form of cookies and candy. Discover the insidious ways it can creep into your diet with 9 Sneaky Sources of Sugar.
Planning your responses to hunger may help you shed fat faster, according to Dutch researchers. Dieters who wrote a list of "if, then" statements ("If I'm hungry at 4 p.m., then I'll have a few almonds.") lost more weight and stuck to their diets better than those who didn't put pen to paper. A specific plan may help you avoid poor choices when hunger strikes, the scientists say. Schedule safe snacks for your weakest times, and switch them up every few weeks. What foods should you avoid? Start with these 25 New "Healthy" Foods That Aren't.