Gut bacteria could play a crucial role in diminishing the life-threatening symptoms of anorexia nervosa and implementing a more permanent cure.
The eating disorder Anorexia Nervosa affects millions of men and women around the world, and according to researchers at the UNC School of Medicine, it has the highest mortality rate of any psychological disorder. Psychiatrists often struggle to find suitable and lasting treatments because the complex recovery process differs for each individual. Since there are so many psychological and physical issues at play, people struggling with anorexia frequently limbo back and forth in the recovery and relapse process.
The key to the cure may have a lot to do with gut bacteria, researchers say. In comparison to healthy individuals, people with anorexia have very different microbial communities nesting in their gut. This bacterial imbalance is associated with some of the psychological symptoms associated with anorexia, like anxiety, depression, and further weight loss. By altering the microbe communities, scientists believe they could debilitate these symptoms.
Previous studies have linked gut bacteria to weight regulation, but the researchers at UNC wanted to take it a step further and observe its effect on mood. For the study, they collected two different fecal samples from women with anorexia to contrast and compare — one when they were first admitted into the UNC Center of Excellence for Eating Disorders and one when they were discharged after weight restoration. Susan Kleiman, a graduate at the UNC Center for Gastrointestinal Biology and Disease, analyzed the composition and diversity of the gut microbiota in each sample, finding significant differences between admission and discharge.
Microbial diversity is a sign of better overall health, and Kleiman found the samples taken at admission had much fewer types of bacteria. Upon release, the gut bacteria had diversified, but it was still significantly less diverse than samples taken of healthy individuals.
Mood is one of the most difficult symptoms to regulate among people with anorexia, and the researchers noticed that as gut bacteria diversified, the participants’ moods improved. Now, the study’s senior author, Ian Carroll, plans to take the research even further. He concocted a team of nutrition specialists, psychologists, and biologists in order to see if altering the gut microbiota could help with weight regulation.
"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 explained in a press release. "This suggests that gut microbes mediate weight gain or loss."
So in the future, could gut bacterial “transplants” become a way to heighten the moods of people with anorexia as well as help them put on a few pounds? Carroll and his team still have to further research the method, but the National Institutes of Mental Health just awarded them a five-year $2.5 million grant to move forward with the promising work.
“We’re not saying that altering gut bacteria will be the magic bullet for people with anorexia nervosa,” Carroll says. “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.”
Essentially, altering gut bacteria has the potential to make the recovery process of anorexia less uncomfortable by helping patients regulate their weight with more positive mindsets. The key to curing the most lethal psychological disorder could be on the brink of discovery.