Scientists made the surprising discovery that it really matters how you cook your meat, and cooking it the wrong way could have a severe impact on your health. A report presented at an American Heart Association conference reveals evidence that grilling meat can raise your risk of having high blood pressure, as well as eating meat that is cooked well done.

The findings are based on a huge study that examined thousands of people participating in the Nurses’ Health Study. Researchers examined in detail the cooking methods used by people on a regular basis in the study, and they were surprised by the results.

The report found that regular consumers of grilled meats were at a 17 percen thigher risk of having higher blood pressure than average, while people who cooked food to well done were at a 15 percent higher risk. The results applied for beef, chicken, and fish, the researchers said.

“Grilled or well-done beef, chicken or fish may raise the risk of developing high blood pressure among people who regularly eat those foods, according to preliminary research presented at the American Heart Association’s Epidemiology and Prevention | Lifestyle and Cardiometabolic Health Scientific Sessions 2018, a premier global exchange of the latest advances in population based cardiovascular science for researchers and clinicians,” reads the AHA statement.