Diets rich in milk could be behind the growth in cases of inflammatory bowel disease because they fill our guts with “bad bacteria”, a study on mice suggests.
The high amounts of fat we consume today is altering the way we digest our food and allowing harmful bacteria to flourish in our bodies, researchers said.
Changing the balance of bacteria in our guts could relieve the symptoms of the increasing number of people complaining of inflammatory bowel diseases (IBDs) which affect one in 350 people in Britain, they said.
Diseases like Crohn’s and ulcerative colitis – the condition which last year put Manchester United midfielder Darren Fletcher’s career on hold – are caused by the inflammation of the gut, causing symptoms including abdominal cramps and diarrhoea.
Researchers from the University of Chicago studied the effects of varying diets on mice which were genetically engineered to make them prone to IBDs.
One third of mice fed diets which were low in fat or high in polyunsaturated fats developed colitis, compared with two thirds of those fed high amounts of saturated milk fats.
Because these fats – a common component of processed foods – are hard to digest the body has to fill the gut with more bile, altering the balance of bacteria which grow there, the researchers said.
One type of bacterium called Bilophila wadsworthia, normally extremely rare in mouse gut, multiplied so much that it accounted for six per cent of all bacteria in the guts of mice fed the high saturated fat diet.
Prof Eugene Chang, who led the study, said it could lead to new treatments which allow the profile of gut bacteria to be “reshaped” without significantly changing patients’ lifestyles.
Dr Roy Sleator, of the Cork Institute of Technology, who was not involved in the study, told the BBC: “Not only do the authors provide, what is in my opinion, the first credible explanation as to how Western diet contributes to the unusually high incidence in inflammatory bowel disease; they also suggest an effective means of dealing with such diseases, by simply reshaping the microbial balance of the gut.”