A chemical in breakfast food has raised concerns after researchers linked it to an increased risk of heart attack and stroke. Acrylamide, a chemical formed during cooking, could raise the chances of these cardiovascular emergencies by up to 60%, according to a recent study.

Spanish researchers reviewed data from over 100,000 individuals across dozens of studies since 2007. Their findings, published in the Nutrients journal, revealed that acrylamide intake is associated with a higher risk of cardiovascular events and deaths from conditions like heart attacks and strokes.

Acrylamide is a chemical in breakfast food that forms when starch-heavy foods, such as bread and potatoes, are heated through processes like baking, frying, or roasting. Burnt carbohydrates, such as overly toasted bread, contain especially high levels of acrylamide—a concern for many who consume toast as part of their daily breakfast.

The study found that diets with higher levels of acrylamide exposure significantly increased the risk of cardiovascular death by 33% to 66%. For vulnerable populations, like those at risk for type 2 diabetes, the danger was even greater—showing up to an 84% increased risk of death from cardiovascular issues.