If you're among the 30% of Americans who sleep less than six hours a night, here's one simple way to whittle your waistline: catch more Zs. A 16-year study of almost 70,000 women found that those who slept five hours or less a night were 30% more likely to gain 30 or more pounds than those who slept 7 hours. The National Institutes of Health suggest adults sleep seven to eight hours a night.
Carb crazy? Consider this: Refined carbohydrates, such as bread, potatoes and rice, create a surge in insulin that in turn drives down your resting metabolic rate, explains Aronne. "It's important to keep carbohydrates in your diet, but really focus on fruits, vegetables and whole grains, which have less of an effect on insulin levels," he explains. And when buying whole-grain breads and cereals, make sure the first ingredient listed is whole wheat, whole oat or cracked wheat.
It turns out that capsaicin, the compound that gives chile peppers their heat, can also fire up your metabolism. Eating about 1 tablespoon of chopped peppers (red or green) boosts your sympathetic nervous system (responsible for your fight-or-flight response), according to a study published in the Journal of Nutritional Science and Vitaminology. The result: a temporary metabolism spike of about 23 percent. Stock up on chile peppers to add to salsas, and keep a jar of red-pepper flakes on hand for topping pizzas, pastas, and stir-fries.
Also some research shows that the human body is primed to consume most of its calories during daylight hours. But the lifestyle is problematic for many: Because family meals and dinners with friends often are scheduled for after sunset, "people who try to stop eating after 7pm can’t do it every day for the rest of their lives," says Dr. Seltzer, who supports an alternative strategy: Eating a hearty meal at your regular dinnertime.
Close the Kitchen at Night. Establish a time when you will stop eating so you won't give in to the late-night munchies or mindless snacking while watching television. "Have a cup of tea, suck on a piece of hard candy or enjoy a small bowl of light ice cream or frozen yogurt if you want something sweet after dinner, but then brush your teeth so you will be less likely to eat or drink anything else," suggests Elaine Magee, MPH, RD, WebMD's "Recipe Doctor" and the author of Comfort Food Makeovers.
Intermittent fasting—limiting your eating hours to just eight, say between 10:30 and 6:30—has gained popularity as a way to shake up your metabolism, and it just might work. “There is a lot more research that needs to be done but it does seem to benefit some people, particularly men,” says Angel Planells, RD, a spokesperson for the Academy of Nutrition and Dietetics based in Seattle. Another approach is to fast—or eat next to no calories (500-600 calories total)—two non-consecutive days a week. (You can eat normally the other five days.) The tactic seems to increase fat burning. “When your body isn’t getting fuel, it will start burning fat,” Planells says. Read about this woman’s experience with intermittent fasting.