The UNC School of Medicine has released a study, specifying that people with anorexia nervosa have psychological symptoms associated with their microbial gut community. Previous studies have associated depression and neurotransmitters with gut bacteria. Aneroxia Nervosa affects more than 3 million Americans with the highest mortality rate.
The study, published in the Psychosomatic Medicine, specifies that gut bacteria are linked to digestive health and immunity, (also called the gut brain axis)”. The research participants consist of 16 women with anorexia nervosa after they were first admitted into UNC Center of Excellence for Eating Disorders. The researchers took fecal samples after admission and after discharge from UNC.
“Other studies have linked gut bacteria to weight regulation and behavior,” said Ian Carroll, PhD, senior author of the paper and assistant professor of medicine in the UNC Center for Gastrointestinal Biology and Disease. “Since people with anorexia nervosa exhibit extreme weight dysregulation, we decided to study this relationship further.”
Carroll said, “We’re not able to say a gut bacterial imbalance causes the symptoms of anorexia nervosa, including associated symptoms, such as anxiety and depression. But the severe limitation of nutritional intake at the center of anorexia nervosa could change the composition of the gut microbial community. These changes could contribute to the anxiety, depression, and further weight loss of people with the disorder. It’s a vicious cycle, and we want to see if we can help patients avoid or reverse that phenomenon. We want to know if altering their gut microbiota could help them with weight maintenance and mood stabilization over time.”
The fecal samples from the research participants at clinic admission had less diverse gut bacteria with fewer differential gut bacteria. Upon hospital discharge, the microbial diversity had increased, and was associated with a significant improvement in mood.
“Over the past 10 years, prominent researchers have learned that when you take gut microbial communities of an obese person and put it in germ-free mice — which are maintained in sterile conditions and lack intestinal microbiota — the mice gain more weight than germ-free mice that have been colonized with a gut microbiota from a lean individual,” Carroll said. “This suggests that gut microbes mediate weight gain or loss.”
“We’re not saying that altering gut bacteria will be the magic bullet for people with anorexia nervosa,” Carroll said. “Other important factors are at play, obviously. But the gut microbiota is clearly important for a variety of health and brain-related issues in humans. And it could be important for people with anorexia nervosa.”
Susan C. Kleiman, Hunna J. Watson, Emily C. Bulik-Sullivan, Eun Young Huh, Lisa M. Tarantino, Cynthia M. Bulik, Ian M. Carroll. The Intestinal Microbiota in Acute Anorexia Nervosa and During Renourishment. Psychosomatic Medicine, 2015; 1 DOI: 10.1097/PSY.0000000000000247