Too Much Exercise Linked to Eating Disorders

Excessive exercise associated with lifetime risk of eating disorders

(RxWiki News) Eating disorders can be about much more than what a person eats or doesn't eat. For some people, over-exercising may be a sign of an eating disorder.

In a recent study, researchers looked at the relationship between excessive exercising and the risk of developing an eating disorder.

These researchers found that women who exercised excessively were more likely to develop an eating disorder over their lifetime.

"Consult a doctor about concerns over your eating and exercise habits."

The lead researcher in this study was Elzbieta Kostrzewa from the Department of Translational Neuroscience in the Brain Center Rudolf Magnus at the University Medical Center Utrecht in the Netherlands.

Bulimia and anorexia are eating disorders found most often in females aged 15 to 25. People with bulimia often binge eat then do something to prevent themselves from gaining weight, such as vomiting. People with anorexia have a distorted body image and diet excessively. Both bulimia and anorexia can result in extreme weight loss, severe malnutrition, starvation and death.

In a Spotlight on Eating Disorders, the director the the National Institute of Mental Health, Dr. Tom Insel, estimated that one in 10 people with anorexia die. Researchers are interested in trying to identify people who are at risk of developing anorexia.

There were 778 women aged 30-55 years old included in this study. The average age of the women was 44 years old.

Data was gathered on age, body mass, activity level, eating disorder diagnosis and answers on the Eating Disorder Inventory (EDI-III).

The EDI-III has three parts: the Drive Toward Thinness (DTT) that asks about how important being thin is to the person; the Bulimia Subscale (BS) that asks the participant whether they were ever bulimic; and the Body Dissatisfaction survey (BD) that asks how the person feels about their body.

The amount of exercise study participants reported was categorized as excessive if they spent five or more hours a week exercising.

The researchers analyzed the responses to the surveys and questionnaires to see if there were any associations between the answers. They used a Generalized Estimated Equations model to see if the risk of getting an eating diagnosis was associated with excessive exercise, age, body mass or a diagnosis of eating disorder.

The results showed a positive relationship between excessive exercise and eating disorders. Women who exercised excessively had a 2.64 times greater lifetime risk of developing an eating disorder than women who did not exercise as much.

The study also showed that the odds of a woman getting an eating disorder diagnosis any time in life were 1.09 higher if she had higher scores on the Bulimia Scale. This meant that experiencing bulimia was associated with a higher lifetime risk of eating disorders.

The results did not show a relationship between excessive exercise and body mass or other eating disorders that were reported on the EDI-III.

"Exercise can certainly be excessive and unhealthy depending on the feelings you have around it," said Julie Gladnick, MA, LMFT, Licensed Marriage and Family Therapist in private practice in Denver, Colorado.

"Although I don't necessarily agree that 5 hours of exercise a week is excessive, it is more about your attitude than the number of hours. If, like any other coping mechanism, you're wellness becomes dependent on getting a workout in, and your mood fluctuates greatly depending on that, it may be a red flag," Gladnick told dailyRx News.

"Exercise, in moderation, is an excellent way to maintain a healthy lifestyle and manage feelings of anxiety and depression, assuming you feel good about it and not pressured," she said.

A limitation of this study was that the researchers asked the participants to reveal if they were ever given a diagnosis of an eating disorder or believed they had an eating disorder. This was not confirmed by a doctor and because of that, those people who said they had anorexia in this study may not have the same high risk of death as Dr. Insel reported.

Another limitation of the study was the definition of excessive exercise that the researchers used. It may be argued that five hours of exercise a week is not excessive. Nevertheless, that is the amount of exercise the researchers defined as excessive and for which they found an association with a greater lifetime risk of eating disorders.

This study also used data obtained in a different study that involved twins from Great Britain. The fact that these subjects were twins was not part of what the study was designed to investigate.

This study appeared in the December 30 issue of Psychiatry Research.

Funding for this study was from a ZonMW VIDI Grant from the Netherlands Organization for Scientific Research. The researchers did not disclose a conflict of interest.

Review Date: 
December 7, 2013