People with obesity or diabetes who consume 20% or more of their daily calories from fast food are more likely to develop liver steatosis compared to those who ate less fast food or none, a study shows.

Findings from the research letter published in Clinical Gastroenterology and Hepatology suggest that even a relatively modest amount of fast food consumption can be harmful.

“If people eat one meal a day at a fast-food restaurant, they may think they aren’t doing harm,” said Dr Ani Kardashian, a hepatologist with University of Southern California’s Keck School of Medicine, in Los Angeles.

“However, if that one meal equals at least one-fifth of their daily calories, they are putting their livers at risk.”