Could the Microbiome Cure Eating Disorders?
Joyce Park stashed this in Science
Mind-gut connection seems pretty key to understanding and treating eating disorders.
Refeeding, when high-calorie hospital diets provide many more nutrients, allows for a more diverse microbiome.
“And a diverse microbiome is a healthy microbiome,” Bulik says.
The high calorie refeeding diet also has a paradoxical effect on many people with anorexia, causing their metabolisms to become extremely inefficient, such that calorie needs go even higher. Many with anorexia need upwards of 3,500 to 4,000 calories per day to gain a pound a week. No one really knows why this is, but Bulik and Carroll intend to investigate their microbial samples to see whether particular microbial species might play a role in this.
She had hurt her microbiome so much it caused her pain.
There was another reason I avoided eating: It was really uncomfortable. I’m not talking psychic discomfort, although that was plenty real. I’m talking severe bloating, constipation (there’s a reason everyone on eating disorder units talks about pooping), gas, cramping, and never-ending stomachaches. I had been hospitalized before, and as much as knowing the drill gave me some small amount of comfort, I also knew what was coming. Learning that I was right gave me little comfort.
30 million Americans have eating disorders.
Our guts are home to trillions of microbes that help us digest our food and keep harmful pathogens from taking over. A host of studies in recent years have shown that changes in diet rapidly shift the populations of microbes living in our guts, and eating disorders, according to a recent study in the International Journal of Eating Disorders, are likely no different. Knowing that there’s a difference is one thing, but knowing what that difference means is quite another.
“So far, we have focused on gut-related disorders such as C.diff infections and Inflammatory Bowel Disease, but we wanted to find out if perhaps this largely psychological disease had any microbial signature. Today there are roughly 30 million individuals suffering from anorexia, bulimia, and binge eating disorder, yet, research in this area beyond psychological intervention and treatments is largely unexplored. We want to see how these diseases might be impacting the gut or vice versa,” said Orli Kadoch, Research and Collaborations Lead at uBiome, in an email.
Scientists call it the gut-brain axis, and it’s clear that the microbes in the gut can have an effect on the brain.
One study found that mice raised in a germ-free environment, and therefore without a microbiome, showed significantly less anxious behavior than their germy counterparts. A more recent study found that a daily probiotic supplement significantly decreased anxiety in humans.
Studies have also shown, for example, that gut microbes can affect weight gain. Fecal transplants from obese to lean mice caused the more svelte rodents to gain weight, and vice versa. And scientists have documented a case report of a woman who started gaining large amounts of weight after receiving a fecal transplant from her larger-bodied daughter.
A pilot study of microbiomes in people hospitalized for anorexia revealed marked differences between admission and partial weight restoration. At their lowest weight, the study participants had gut microbes that were significantly less diverse than at a more normalized weight. The reason, explains Bulik, is that the extremely low-calorie diets of those with anorexia create a harsh environment where it’s tough for even gut microbes to get enough energy. The few species that can survive are those that can eke out a living on very few calories.
“It practically defies the laws of physics how some of these people can live on so little for such a long period of time and still be alive,” she says.
It’s unlikely that these studies will tell us everything we need to know about the microbiome as it relates to eating disorders, but it’s a start.
And beyond understanding the biology of eating disorders, this microbiome research may do something more immediate and practical for sufferers: make the process of renourishment less painful.
“No one really knows what makes refeeding so uncomfortable. Maybe we can harness the bugs through a targeted probiotic supplement to make the process easier to people can focus more on getting well,” Bulik says.