Severely restricting your calorie intake for fast weight loss causes your body to go into "starvation mode," which means your metabolism slows because it's not getting enough calories. If you've fallen prey to a low-calorie fad diet and fear your weight-loss rate has plummeted because of it, there is hope. Getting enough calories, maintaining lean body mass and building muscle can help jump-start your sluggish metabolism.
Metabolism and Starvation Mode
The effectiveness of your metabolism rests on three things: your basal metabolic rate, daily activity and the thermic effect of food. Most of the calories you eat are used to support your BMR, which includes basic body functions such as breathing, heart rate and maintenance of muscle and tissue. When you don't eat enough calories, your body's metabolism slows down to limit overall energy expenditure. The McKinley Health Center reports that your metabolism may slow down by up to 30 percent when you don't eat enough.
Getting Enough Calories
If you want to get out of starvation mode, eat enough calories. The amount of calories you need to continue to lose weight without lowering your metabolism depends on your age, gender, activity and body size. Start by tracking your current intake and rate of weight loss. Eat enough calories to lose weight at a rate of 1 to 2 pounds a week. Add 100 calories to 200 calories a day to your current intake until you're losing at the recommended rate. To prevent a slowdown in metabolism, no one should eat fewer than 1,200 calories a day; men shouldn't eat fewer than 1,800 calories a day, according to the McKinley Health Center.
Muscle naturally burns more calories than fat. The reason you want to lose weight at a slow rate is so that you lose fat, not your calorie-burning muscle. In addition to preserving your muscle when trying to lose weight, you may also be able to get yourself out of starvation mode by building muscle mass. Weightlifting, pushups, situps and squats are all resistance-training exercises that can help build muscle and give your metabolism an extra boost.
Eating does help you burn calories, but it's not a major player in your overall metabolism, according to the McKinley Health Center. But that doesn't mean it's not an important part of your diet for weight loss. If you were severely restricting your calorie intake to slow down your metabolism, it's possible you weren't getting all the nutrients your body needs for good health. Your healthy weight-loss diet should include foods from all the food groups -- fruits, vegetables, grains, lean proteins and dairy -- to replenish your body. Eat regularly, three meals plus one snack a day, to keep hunger away and energy levels even.
- Weightlossresources.co.uk: Dieting and Metabolism
- McKinley Health Center: Breaking Down Your Metabolism
- PLoS: Metabolic and Behavioral Compensations in Response to Caloric Restriction: Implications for the Maintenance of Weight Loss
- U.S. Department of Agriculture and U.S. Department of Health and Human Services: Dietary Guidelines for Americans, 2010
- FamilyDoctor.org: What It Takes to Lose Weight