Laboratory studies show that exposing meats to direct flame, smoke and intense heat – like when you grill or broil – can cause the formation of carcinogens (cancer-causing substances).
Cooking methods that involve less heat, such as microwaving, baking, steaming and poaching, do not promote the formation of these substances.
According to the American Institute for Cancer Research (AICR), cooking poultry, fish and red meats (beef, pork, lamb) at high temperatures, especially over an open flame, produces substances called heterocyclic amines, or HCAs, which have been shown to cause cancer in laboratory animals.
In addition to HCAs, another class of cancer-promoting substances, called polycyclic aromatic hydrocarbons, or PAHs, is formed when fat from meat, poultry or fish drips onto hot coals or stones, causing flare-ups. PAHs are deposited onto the food when smoke and flames are allowed to reach the food.
Evidence that HCAs and PAHs increase the risk of cancer in humans is “limited but suggestive,” according to the AICR.
Most experts agree that plant-based foods do not form these undesirable substances. So, for delicious and healthful options, try grilling vegetables, veggie burgers and fruit slices for variety, and cut down on meat, poultry and fish.
When you do grill meats and fish, you can use several strategies to help minimize the formation of carcinogens. Marinating is one strategy that can significantly protect animal protein from forming carcinogens. Flipping frequently to prevent charring, removing excess fat from meat before cooking, and decreasing grilling time by pre-cooking in the microwave also can be helpful.
Here are more tips to help minimize the formation of carcinogens from grilling:
- Clean the grill thoroughly before cooking to remove any charred food remaining from previous uses.
- If using starter fluid on charcoal, allow the excess to burn off before putting food on the grill. Never reapply starter fluid while cooking.
- Choose lean cuts of meat rather than higher-fat varieties such as ribs or sausages. Also, trim any visible fat from meat and remove skin from poultry before cooking.
- Marinate meat before cooking, using an oil-free marinade.
- Consider partially pre-cooking meat in the microwave, oven, or on the stove to help reduce grilling time. Just make sure the pre-cooked meat is immediately transferred to a pre-heated grill to complete the cooking.
- Grill at a lower temperature, away from direct flame and raise the cooking rack to the highest position. Cook meat in the center of the grill and move coals to the side to prevent fat and juices from dripping on them.
- Use tongs or a spatula to turn food. Piercing meat with a fork allows juices and fat to drip down onto coals and cause flare-ups.
- Line the grill rack with foil and poke small holes in the foil so that some fat can drain down but not all of the smoke can come back onto the meat.
- Avoid charring meat and don’t eat any part that is especially burned and black.
- Flip frequently. Research shows that grilling hamburger patties at a lower temperature and turning them often accelerates the cooking process, reduces HCA formation and still kills bacteria effectively. It also enhances even cooking throughout the pattie.
Beyond Grilling
A recently published AICR report concluded that diets high in red meat and especially in processed meats are a “convincing cause of colorectal cancer.” The AICR recommends limiting consumption of cooked red meat (beef, pork and lamb), whether grilled or otherwise, to no more than 18 ounces per week. (That’s about six quarter-pound hamburgers.) Processed meats, such as hot dogs, sausages, bacon, ham, cold cuts, etc., also should be limited. In an analysis of the available evidence, the AICR found that every 3.5 ounces of processed meat eaten per day increased the risk for colorectal cancer by 42 percent.