A diet high in sugar and fat could significantly increase the risk of inflammatory bowel disease, a new study has found.
Researchers from Washington University School of Medicine and Cleveland Clinic found that a Western diet causes damage to the immune cells, called Paneth cells, in the gut.
When Paneth cells aren't functioning properly, inflammation in the gut increases, putting people who are obese at risk of developing infections or inflammatory bowel disease as the cells are unable to fight off any disease-causing microbes.
Inflammatory bowel disease is a term used to describe two long-term chronic conditions: ulcerative colitis and Crohn's disease. Symptoms include stomach cramps, bloody diarrhoea, weight loss and fatigue.
Lead author Ta-Chiang Liu and senior author Thaddeus Stappenbeck analysed data from 400 people, and found that high body mass index (BMI) was associated with abnormal and unhealthy Paneth cells.
And the higher the BMI, the worse the Paneth cells looked.
"Obesity wasn't the problem per se. Eating too much of a healthy diet didn't affect the Paneth cells. It was the high-fat, high-sugar diet that was the problem," Liu explained.
He called for more research to be done into the association between a Western diet and unhealthy Paneth cells, and warned that even if a person changed their diet, it could be too late to help the cells repair themselves.
"People have a suboptimal lifestyle for 20, 30 years before they become obese. It's possible that if you have Western diet for so long, you cross a point of no return and your Paneth cells don't recover even if you change your diet. We'd need to do more research before we can say whether this process is reversible in people," he warned.