Weight Loss & Starvation Mode

Weight Loss & Starvation Mode

Anytime you eat fewer calories than you take in you'll lose weight, barring any medical condition that inhibits weight loss. Eating too few calories in an effort to shed pounds isn't healthy, however, and it isn't the most effective way to weight loss. When you do that, your body goes into starvation mode to conserve energy, and you may find yourself experiencing a weight-loss plateau, not to mention health problems from not getting the nutrients your body needs. Always consult with your physician before dieting.

Starvation Mode Basics

 Your body is equipped with its own starvation defense mechanism, which has evolved over millions of years to protect you during times when food was scarce -- a problem most people don't have today. When you take in too few calories to support activity and normal physiological functioning, your body adapts by reducing the amount of energy it uses to accomplish tasks. Your body may also turn to lean muscle mass for energy in order to conserve its valuable fat stores, just in case it doesn't receive more food anytime soon.

Starvation Mode's Effects on Weight Loss

 Your body's adaptation causes your basal metabolic rate, which accounts for more than 60 percent of the calories your body burns daily, to slow down. This, in turn, causes you to burn fewer calories, even though you might be performing exactly the same tasks as when you were eating a regular diet. In addition, the gradual loss of muscle mass reduces your body's calorie-burning ability because the body uses more calories to maintain lean muscle mass than it does fat mass.

 

How Low Can You Go?

It's not clear what calorie intake level brings on starvation mode and whether the effects are increased the lower the calorie intake. In an article on the Waldo County General Hospital website, Dr. Kristie Leong writes that 1,200 calories per day is the absolute lowest level one should drop to when dieting. Otherwise, Leong says, the body will start to conserve fat, making weight loss more difficult.

Very-Low-Calorie Diets

In some instances, a very-low-calorie diet of fewer than 800 calories per day may be prescribed by a doctor if the patient has a significant amount of weight to lose. The diet, which consists of specially formulated liquid shakes and bars, is meant to kick-start weight loss for obese people who may experience complications, like high blood pressure, because of their excess weight. These diets must be undertaken only under medical supervision due to the dangers of consuming too few calories and losing weight rapidly. These include fatigue, constipation, nausea and diarrhea as well as more serious side effects like gallstones.

  A Safer Way to Lose Weight

According to the Weight-Control Information Network, very-low-calorie diets, requiring medical supervision, generate the same amount of weight loss as low-calorie diets over the long term. Lose weight safely and effectively, by reducing your current calorie intake by 500 each day, which will lead to weight loss of 1 pound per week. Add an hour of exercise to your daily schedule to burn another 500 calories each day for a 2-pound-per-week sustainable weight loss.
 

How Much to Eat to Avoid Starvation Mode?

Starvation mode refers to the tendency of the human body to conserve energy stores in times when it is not receiving enough nutrients to fuel basic metabolic functions. The two primary changes that your body makes during times of starvation are slowing down your metabolism and conserving fat stored in adipose tissue. Instead of burning stored fat for energy during starvation mode, your body actually prefers the protein stored in your muscle tissue. The state of starvation should be avoided not only because slowing down your basal metabolic rate will make future weight loss and weight maintenance more difficult, but also because it isn't an effective way to rid yourself of stored fat.

Basic Cellular Function

The majority of the calories an average person burns each day comes from their basal metabolic rate, also known as resting metabolism. Endurance athletes are the exception to this rule because they burn many calories during training and competition. Your basal metabolic rate is the sum of calories that are used up carrying out cellular functions in your body, such as the creation of hormones, new blood cells and neurotransmitters.

Basal Metabolism Estimate

To obtain a precise calculation of your basal metabolism, you will need to make an appointment with a dietitian or other health professional offering indirect calorimetry. The indirect calorimeter measures the volume of air and oxygen you move in and out of your body for about 10 to 15 minutes to calculate the daily calories necessary to support your body at rest. These tests typically cost between $75 and $250. If you are not able to take advantage of an indirect calorimetry test, you can estimate your resting metabolism with a simple formula. METABOLISM CALCULATOR
For men, use [10 x (weight in kg)] + [6.25 x (height in cm)] - [5 x (age in years)] + 5. 
For women, use [10 x (weight in kg)] + [6.25 x ( height in cm)] - [5 x (age in years)] – 161.

The Big Picture

Basal metabolism is only one part of your daily caloric needs. To get the whole picture, you need to estimate the number of calories your body uses each day from both resting metabolism and your daily activities and exercise. Each pound of weight that you lose requires a caloric shortfall of about 3,500 calories. Because doctors and dietitians recommend that you lose no more than 1 to 2 lbs. per week, it is important to make sure you do not have a caloric shortfall of more than 500 to 1,000 calories per day. Depending on how active you are, that could mean that even if you are eating enough calories to satisfy your basal metabolism, you might not be eating enough for healthy weight loss. Eating less than your total calorie use and more than your basal metabolic rate is the safest and most effective way to lose weight with minimal side effects.

Total Calorie Use

To estimate the number of calories you actually use each day, you will multiply your basal metabolism by an activity factor. Choose an activity factor that closely matches your actual lifestyle – not the lifestyle to which you aspire. If you don't usually exercise and you have a job that involves mostly sitting down, multiply your basal metabolism by 1.2. If you engage in light exercise, gardening or sports one to three times each week, multiply by 1.375. If you engage in moderate exercise, gardening or sports three to five times each week, multiply by 1.55. If you are involved in hard exercise or sports six or seven days per week, multiply by 1.725. If you are extra active and do hard exercise or sports in addition to having a physically active job, multiply by 1.9. If you are somewhere in between two of the activity factors, you can multiply by a number that is in between.

How to Get Your Body Out of Starvation Mode

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 Up

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.

 Eat Right

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.

References

• "American Journal of Clinical Nutrition"; "A New Predictive Equation For Resting Energy Expenditure In Healthy Individuals"; M.D. Mifflin et al; February 1990
• "Advanced Nutrition and Human Metabolism (third edition)"; James Groff et al; 2000
• "Krause's Food and Nutrition Therapy (12th edition)"; L. Kathleen Mahan et al; 2008

• Covenant Health: The Starvation Mode Myth
• Canadian Living: 6 Surprising Health Conditions That Hinder Weight Loss
• MetabolicEffect.com: Starvation Mode: Is It Real? Is it a Myth? What Are the Symptoms?
• NIH Office of Science Education: Section 1: Sources of Energy for the Body
• Time: It’s the Calories, Stupid: Weight Gain Depends on How Much -- Not What -- You Eat
• WeightWatchers: The Starvation Myth
• Waldo County General Hospital: How to Understand the Risks of Eating Too Few Calories
• Weight-Control Information Network: Very Low-calorie Diets
• Centers for Disease Control and Prevention: Losing Weight

• 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