Could Bacteria Cause Some Anorexia Cases?

Anorexia is a well known eating disorder, but the causes of this condition aren’t fully understood.

In the journal “Medical Hypotheses,” researchers from the U.K.’s Lancaster University say they believe anorexia nervosa, as well as conditions like Irritable Bowel Syndrome (IBS) and Chronic Fatigue Syndrome (CFS), may share an underlying autoimmune issue that probably links to bacterial infection.

Currently, anorexia is often thought to result from a combination of factors. Women tend to be more susceptible, though how much this is related to underlying genetic factors remains unclear. Environmental and social pressures, like the close scrutiny society gives to women’s bodies, may also be at play.

Other contributing factors can include childhood or young adult trauma, including intense harassment and physical or sexual assault. Anorexia may also stem from emotional traumas like the loss of a parent.

However, researchers have said that these factors do not satisfactorily explain all cases of anorexia. For example, why do only some people who suffer early-life trauma go on to develop eating disorders?

The researchers in this paper argue that an often overlooked factor is that women are far more likely to develop autoimmune disorders than men. Some statistics suggest that of the eight percent of the population with an autoimmune disorder, about 78 percent of them are women.

This dramatic skew of the gender ratio is also present in anorexia, IBS and CFS.  Thus, researchers argue that autoimmune diseases may be an underlying pathology in these conditions, offering new insight.

For example, previous research has shown that CFS tends to follow a number of infections, including viral hepatitis. Similarly, IBS has been linked to previous episodes of infectious diarrhea. The researchers, therefore, put forward that some kinds of infection cause an immune response that may attack regions of the brain related to mood and perception — and could underpin anorexia.

The researchers write:

Auto-antibodies acting on the (brain’s) limbic system could induce extremes of emotion including disgust and fear.  These then become linked, in the minds of adolescent girls, to culturally determined ideas of what is, and what is not, the ideal body shape and size. It is then a small step for disgust and fear to be directed to food and obesity which the fashion industry currently demonizes.

While this might sound somewhat unorthodox, it isn’t without precedent.

Previous research has suggested that there is a close link between inflammation in the body and the development of depressive episodes. Similarly, other research has suggested our gut biomes — that is, the bacteria that live in our intestinal tracts — may play a part in the development of anxiety and depression when coupled with early-life trauma.

But there are some factors that suggest this theory is not necessarily a perfect fit. Other autoimmune diseases in women tend to manifest in mid-life — when auto-antibodies are high — whereas traditionally, anorexia tends to affect younger women.

That said, this doesn’t refute the theory. On the contrary, it may account for why an unusual abundance of antibodies that target appetite centers have been found in women with anorexia.

Researchers now aim to test this theory, identify possible bacterial culprits and observe the autoimmune response that may lead to these issues.

In terms of treatment options, this theory offers some exciting possibilities. If researchers can demonstrate that they are correct about the autoimmune aspect of anorexia and conditions like IBS and CFS, immune cell transfusions from healthy people could help in the most severe cases. Furthermore, treating gut bacteria may also help to stop the illnesses from being triggered in the first place.

But researchers are not suggesting that there is only one cause of anorexia.

They are simply stating that the biological aspects of this illness may have been overlooked. With new insights, we could get a clearer picture on the complex way in which underlying biological factors, together with environmental stress, can give rise to anorexia.

Ultimately, this new theory could open exciting treatment options for the eight million people or more who suffer anorexia in the United States, including the small – but still significant — proportion who are men.

Photo Credit: Jovo Jovanovic/Stocksy


Elisa F
Elisa F11 months ago

Interesting, thanks for sharing.

william Miller
william Millerabout a year ago


Siyus Copetallus
Siyus Copetallus1 years ago

Thank you for sharing.

Quanta Kiran
Quanta Kiran1 years ago


Marie W.
Marie W1 years ago

Anorexia came to the forefront when skinny models were everywhere.

Carole F.
Carole R1 years ago

Interesting concept.

Veronica Danie
.1 years ago

Thank You!

Cela V.
Cela V1 years ago


Dr. Jan Hill
Dr. Jan Hill1 years ago

An interesting connection which might also explain why post-anorexics have such problematic digestion issues.

Amy B
Amy Belau1 years ago

Seems like this could've been scientifically linked decades ago.