Is light therapy for bulimia nervosa effective? Bulimia is a type of eating disorder where a person restricts their food intake for a time followed by period of binging. After binging, a bulimic experiences guilt and compensates for their overindulgence by vomiting or using laxatives to purge themselves of the food and extra calories. This gives rise to the repetitive “binge and purge” cycle that’s characteristic of bulimia.
Not surprisingly, depression and anxiety are more common in people with bulimia nervosa. Due to the close association of bulimia with mood disorders such as depression and anxiety, doctors sometimes use anti-depressant medications to treat people who suffer from bulimia - with mixed success.
Bright Light Therapy for Bulimia Nervosa
Bright light therapy has been used with some success to treat patients with seasonal affective disorder, a type of depression that’s brought on by the change in seasons - usually the transition from fall to winter. Seasonal affective disorder, or SAD, is thought to be triggered by a lack of sunlight. Since people with bulimia nervosa often experience depression, focus has centered around using light therapy for bulimia nervosa. Does it work?
In a study published in Comprehensive Psychiatry in 1999, a small, double-blind study concluded that bright light therapy improves the symptoms of bulimia nervosa. Thirty-four bulimic females were treated with bright white light or red light (to serve as a placebo) for three weeks. After three weeks of daily light therapy for thirty minutes at a time, the bulimic women who received the bright light therapy had a reduced frequency of binging compared to the placebo group.
This isn’t the only small study to show that light therapy for bulimia nervosa is at least somewhat effective. In a study carried out on twenty-two bulimic patients, researchers found that bright light therapy reduced binging episodes by 46% and purging by 36%. Although it didn’t “cure” the bulimia, it reduced the frequency of “episodes” and almost half of the bright light recipients felt less depressed.
Bulimics and Bright Light Therapy
Why was bright light therapy for bulimia effective in these studies? Some researchers propose that light therapy relieves the underlying depression and makes a bulimia sufferer feel better from a mental standpoint, which may reduce their desire to binge. Light therapy also alters levels of neurotransmitters such as serotonin, which play a role in mood and appetite. In fact, anti-depressants used to treat both depression and bulimia increase levels of serotonin in the brain. Bright light therapy may have the same effect naturally – without the use of drugs.
The studies looking at light therapy for bulimia nervosa have been small in size, so more research is needed before any firm conclusions cam be drawn. On the other hand, this therapy holds promise, and it has the advantage of being completely drug-free. Hopefully, further research will shed more light on this issue.
Compr Psychiatry. 1999 Nov-Dec;40(6):442-8.
WebMD. “Light Therapy Lessens Bulimics’ Binging and Purging”.