Recovering from an Extremely Low Body Weight

By October 17, 2012

I was diagnosed last January with an eating disorder (anorexia) due to my body weight. I am 5’6 and weighed ** lbs. My weight loss was not due to starvation, but seemed to result from excessive exercise and restricted caloric intake. Because I never starved myself, I have not been able to truly accept my physical condition. My doctor recommended I dramatically increase my calories (about 3,000 a day) and discontinue exercising. I have tried to do this, but continue to struggle. I currently have cut my exercise routine more than half and am eating about 2,000 calories a day. I physically do feel better than I did a year ago. I am not as weak, but now experience highs (days with lots of energy/feel good) and lows (days of extreme fatigue/depression). Because I see myself eating so much and exercising so little, I cannot understand why I have not achieved a healthy weight. It has been over a year and I have gained about 5 lbs. My doctor has tried to explain my body is experiencing “hypermetabolism” in which I am starting to burn off the calories and therefore need to continue to eat more/exercise less. Because I was heavier years ago (about 160 lbs.), I struggle with the fear of gaining too much weight and not finding that balance (a healthy weight and exercise routine). Please provide any advice or information about what the body goes through when recovering from an extremely low body weight. – R.

Dear R.,

It sounds like you have been working hard to improve your overall health, but are still facing significant obstacles and struggles. I get the sense from your letter that you are feeling stuck and are ready for change. I hope that some of the information in my response will help you to move forward.

To start, I’ll address your question regarding the physical recovery process from an extremely low body weight. In the first week(s) of increasing calorie intake after underfeeding the body, a person can experience “rebound edema.” This means that the body temporarily retains more fluid than it needs as it adjusts to re-hydration of muscles and the circulatory system, along with digestive changes. Weight can increase significantly with rebound edema, but it is just temporary water weight. Some people experience shortness of breath at this point. In addition, constipation, abdominal pain, and feeling full hours after eating can occur, because the digestive tract has slowed down, contains too few enzymes, and has lost muscle tone from being underfed. Calories need to be increased gradually during this stage, with careful food selections, in order to minimize medical risks and discomfort from these temporary complications.

Another side effect of underfeeding during anorexia is a slowed metabolism (as the body protects itself), but when calories are increased to a healthier level, metabolism also goes through an adjustment process. As eating is normalized, there is a rise in resting energy expenditure—a sign that metabolism is increasing due to improved nutrition, an increase in body temperature and increased T3 level (a thyroid hormone). As a result of a faster metabolism, it can be difficult to gain weight (non-water) for a period of time. Some people also experience sweating after meals and at night during this stage. Again, these issues pass as the body is recalibrated to eating well again.

Recovering from a state of under nutrition can be complicated and does take time and patience. But considering the fact that you have been working to regain weight for over a year and are still really struggling—both physically and emotionally—I strongly urge you to seek out more professional support. A nutritionist who has experience counseling people with eating disorders would be able to answer your questions and provide individualized guidance to get you to a place of better health. She/he can assess your activity level and current calorie needs, as well as help allay your fears of gaining too much weight. This person could also provide useful information to your doctor, as to whether there might be other medical issues that need to be investigated that are making weight gain difficult for you. Check out “Finding a Nutritionist” for ideas, if you haven’t been evaluated by someone before.

Lastly, I suggest that you read through the “Disordered Eating 101” section of our site to better understand anorexia, especially since you have not been able to accept this diagnosis. Also, regarding some of your thoughts and fears about eating, you might find my article, “False Beliefs: Restrictive Eating,” helpful. Here again however, you would benefit tremendously from talking through your issues with a licensed counselor or therapist who specializes in eating disorders. If you are not already seeing someone, I urge you to do so.

With added professional help, you will find that place of balance—a healthy weight, enjoyable exercise, intuitive eating without counting calories, and peace of mind. Please take these next steps. It will be so worth the effort.