An increase in the amount of junk food consumed by young adults could have led to a soaring number being diagnosed with a serious bowel problem, experts have said.
The warning comes as new figures suggest that the number of 19 to 29-year-olds admitted to hospitals in England suffering from Crohn's disease has risen by almost 300% in a decade.
The statistics, obtained by BBC Newsbeat from the Health and Social Care Information Centre, show that in 2003/4 there were 4,937 young adults admitted to hospitals in England for the condition and in 2012/13 there were 19,405 people admitted.
Dr Sally Mitton, a consultant gastroenterologist at St George's Hospital in south-west London, told Newsbeat: "If you have a lot of junk food before your diagnosis it actually makes it more likely that you will develop Crohn's disease."
"Also people have noticed those who have lots of antibiotics - particularly in younger life - also seem to be more likely to develop this condition.
"All the centres that get lots of referrals have noticed an increase over the last few decades."
The condition, which is caused by inflammation of the lining of the digestive system, can lead to diarrhoea, abdominal pain, fatigue and weight loss.
Three-quarters of people with Crohn's, which affects one in every 1,000 people in the UK, will need bowel reconstructive surgery at some point in their lives.