Does Extreme Dieting Decrease Your Metabolism?

Losing weight can be challenging, and if you have a busy life, taking time out to exercise or plan a healthy diet can be difficult. In addition, if a social event is coming up, you may want to lose weight quickly to fit into a special outfit. This may lead to following an extreme diet to get rid of the extra weight quickly. However, extreme dieting can cause health problems and slow metabolism -- to the point weight loss is hindered.

Metabolism

When it comes to weight loss, the bottom line is that you must take in fewer calories than you burn. However, to avoid health problems, you must eat enough calories to support metabolism and prevent nutritional deficiencies. Metabolism refers to the calories your body burns to digest the food you eat and turn it into energy. Your basal metabolic rate, or BMR, is the additional number of calories your body burns at rest just to survive and support functions such as breathing, circulation, muscle contraction, digestion and others. When developing a healthy weight-loss program, you must first figure out how many calories you need each day to support your BMR.

Formula for BMR

If you are female, your BMR is equal to 655 plus (4.35 x your weight in lbs.) plus (4.7 x your height in inches) minus (4.7 x your age in years). If you are male, your BMR is equal to 66 plus (6.23 x your weight in lbs.) plus (12.7 x your height in inches) minus (6.8 x your age in years). If you tend to be sedentary, multiply your BMR by 1.2. If you do light activity during the day, multiply your BMR by 1.375. If you are moderately active during the day, multiply by 1.55, and if you are very active multiply your BMR by 1.9. This will give you the number of calories you need each day to maintain your current weight.

Extreme Diets

Since 1 lb. is equal to 3500 calories, to lose 1 to 2 lbs. per week, it is necessary to subtract 500 to 1000 calories from the number needed to support your current weight. As you lose weight, you need to recalculate your daily caloric needs. However, you must eat enough to support metabolism, because if you cut calorie intake too low, your metabolism will slow down to conserve energy. If your body does not know when the next meal is coming, it will hold onto the calories it has. In addition, since extreme diets cannot be followed long term, once the diet is abandoned, any weight that was lost will be regained. A safer and more effective weight-loss program is one that combines healthy eating with regular exercise.

Health Concerns

Extreme diets not only slow metabolism, they also cause serious health concerns. To avoid complications, the University of Maryland Medical Center suggests not dropping below 1100 calories each day. Going lower can cause malnutrition, fatigue, headaches, irregular or missed periods, irritability, hair loss, gallstones, dizziness, a loss of muscle mass and many other health problems. In severe cases, taking in too few calories can be fatal. For those who are at a high risk of weight-related medical conditions, very low-calorie diets are an option. However, these diets are short term and medically supervised, and they are designed to be combined with developing healthy eating and exercise habits.

Solution

Long-term successful weight loss is achievable through a healthy diet, regular aerobic exercise to burn off calories and strength training to improve muscle mass. All of the above will help to naturally boost metabolism, so that extra pounds can be safely shed and kept off. The goal is to lower your percent body fat and increase your percent of muscle mass, because muscle requires more calories to survive than fat does, even at rest.