Unable to resist eating at least two servings of grilled, broiled, or roasted fish, chicken or beef a week? Beware! High-temperature cooking releases chemicals that may raise your blood pressure levels, a precursor for many cardiovascular diseases, finds a Harvard study.The findings showed 17 per cent higher risk of developing high blood pressure among those who grilled, broiled, or roasted beef, chicken or/and fish more than 15 times a month, compared with less than four times a month.The risk was 15 per cent higher among those who prefer their food well done, compared with those who prefer rarer meats.The study showed that when meat protein is charred or exposed to high temperatures, it produces chemicals known as heterocyclic aromatic amines (HAAs), which also raise the risk of hypertension. "The chemicals produced by cooking meats at high temperatures induce oxidative stress, inflammation and insulin resistance in animal studies, and these pathways may also lead to an elevated risk of developing high blood pressure," said lead author Gang Liu, postdoctoral research student at the Harvard T.H. Chan School of Public Health in Boston.Oxidative stress, inflammation and insulin resistance affect the inner linings of blood vessels, and are associated with the development of atherosclerosis, the disease process that underlies heart disease and causes the arteries to become narrowed."Our findings suggest that it may help reduce the risk of high blood pressure if you don't eat these foods cooked well done and avoid the use of open-flame and/or high-temperature cooking methods, including grilling/barbequing and broiling," Liu said.The results were presented at the American Heart Association's Epidemiology and Prevention, Lifestyle and Cardiometabolic Health Scientific Sessions 2018 in New Orleans. For the study, the team analysed cooking methods and the development of high blood pressure in a total of 103,941 men and women who regularly ate beef, poultry or fish.