Scientists say you don’t have to smoke to get lung cancer—you could just eat a lot of bread.

In a new study, researchers at the University of Texas found that participants whose diets had high glycemic indexes—meaning high amounts of certain types of carbohydrates—were more than twice as likely as those with low indexes to develop lung cancer.

Even more startling, the at-risk participants had never smoked a cigarette.

The study’s lead researcher cautioned that this does not prove an absolute link between such diets and lung cancer. However, he said lowering your intake of such high-glycemic carbs—like those in white bread and white potatoes—could lower your risk of contracting the disease.