According to new research published in The Proceedings of the National Academy of Sciences, people who consume diets rich in fiber are at an increased risk of contracting Escherichia coli (E. coli) which can lead to O157:H7 infection and severe disease.

Escherichia coli, which is also known as E. coli, is a bacterium that is found in the gut of endotherms (warm blooded organisms). Most E. coli strains are of no harm to human health, except for serotype O157:H7, which is a leading cause of food poisoning in humans and can eventually become life-threatening.

The study found that "dietary choice affects Shiga toxin-producing Escherichia coli (STEC) O157:H7 colonization and disease."

Uniformed Services University of the Health Sciences (USU) researchers found that mice who were fed high fiber diets (HFD) had very high levels of intestinal butyrate, a gut metabolite which enhances the gut binding-capacity of Shiga toxin - of the bacterium E. coli.

Alison O'Brien, Ph.D., chair of USU's Department of Microbiology and Immunology, led the study, which was funded by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health.

The results revealed that the amount of gut bacteria in mice that were fed a diet rich in fiber was higher compared to those on a low-fiber diet (LFD).

O'Brien said: "These changes led to higher E. coli O157:H7 colonization levels, more weight loss, and greater rates of death in HFD-fed than in LFD-fed STEC-infected mice."

While the study does indicate that there is a connection between risk for E. coli infection and high fiber diets, it doesn't promote changing eating habits that are healthy, especially given that eating fiber is an effective means of reducing the risk of first time stroke, according to a study published in the journal Stroke.

She concluded that "high fiber diets are good for you. However, fresh produce comes from all over the world, so we need to be extra vigilant in keeping our produce free of microbial contaminants."

Written by Joseph Nordqvist