The higher a person’s BMI, the more likely they are to have chronic diarrhoea, a study suggests.

Israeli researchers used data from the US 2009-10 National Health and Nutrition Examination Survey (NHANES) to see whether bowel habits had any relation to BMI.

More than 5000 NHANES participants aged over 20 had completed a bowel health questionnaire, which included illustrations of hard and loose stools to help them accurately describe their own motions.

“Up to 8.5% of obese and 11.5% of severely obese individuals had chronic diarrhoea, compared to 4.5% of normal weight individuals,” the authors wrote in Alimentary Pharmacology and Therapeutics.