Only 11% of Americans correctly estimate their ideal daily calorie requirements, according to one survey. The rest of us tend to overestimate, says Bonnie Taub-Dix, RD, a spokesperson for the Academy of Nutrition and Dietetics. Let's say you assume that consuming 2,000 calories per day will allow you to reach your target weight, but it really takes 1,800: Those extra 200 are enough to keep an additional 20 pounds on your frame.
Lose fat with high-intensity interval training (HIIT). If you're trying to lose weight fast, HIIT training can super-charge your metabolism for upwards of 24 hours after exercising. This means your body will continue burning calories long after you've ended your workout. HIIT burns more calories in less time than steady-state cardio. In one study, researchers looked at two groups, one running for 30 to 60 minutes three times per week, the other doing four to six 30-second treadmill sprints, resting for four to six minutes between each sprint. After six weeks, it was found that the group doing HIIT training lost more weight.
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.