Intermittent fasting increases the risk of colon cancer.
A study on mice revealed that rodents who fasted for 24 hours prior to eating had a "profound" risk of pre-cancerous tumours forming in their gut.
The experts argue that the findings suggest that those on the diet - which is championed by celebrities including Mark Wahlberg and Jennifer Aniston - should avoid foods like charred steaks that are being increasingly linked to the disease in younger people.
Dr. Omer Yilmaz, a biologist at the Massachusetts Institute of Technology (MIT) who led the study, said: "I want to emphasise that this was all done in mice, using very well-defined cancer mutations. In humans it's going to be a much more complex state.
"But it does lead us to the following notion: Fasting is very healthy, but if you're unlucky and you're refeeding after a fasting, and you get exposed to a mutagen, like a charred steak or something, you might actually be increasing your chances of developing a lesion that can go on to give rise to cancer."
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