Do grilled foods cause cancer?
July 15, 2015DW: Is grilled food bad for your health?
Antje Gahl: When you barbecue meat it acquires a distinctive roasted aroma and flavor. But under certain circumstances chemicals are produced that can be harmful to your health. Mainly these are heterocyclic aromatic amines (HAAs) or polycyclic aromatic hydrocarbons (PAHs) and nitrosamines. In animal experiments, high doses of them have been found to be carcinogenic, which, in the case of humans, also cannot be ruled out, especially in connection with colon cancer.
What can you do wrong?
• Put the meat on the grill to early, when the charcoal has not yet burned down to embers and is still too hot.
• Put fatty meat on the grill without something under it to keep the fat from dropping onto the charcoal or the heating element.
• Keep the meat longer than necessary on the grill and eat blackened areas or remove them only by scraping them off.
• Grill vegetables, tofu, etc. until they're too dark. PAHs can be produced when barbecuing fish, fruit, vegetables or tofu, especially if these foods have been marinated.
How do you do it properly?
• To make sure as few harmful chemicals as possible are produced, if you're barbecuing over an open fire use only charcoal or briquettes. The charcoal must burn down to glowing embers with a light coating of ash. That takes 30-40 minutes. Then the grill has the right temperature.
• Don't let the meat lie on the grill for too long. As soon as it's done, remove it so it doesn't dry out too much.
• When grilling directly over charcoal, choose lean meat. Fatty meat should be cooked on an aluminum barbecue tray or tin foil, to keep the fat from dripping onto the embers.
• Don't deglaze the meat with beer. That can also produce PAHs. And cut scorched and blackened areas off grilled food. Scraping them off is not sufficient.
Just what is harmful?
The smoke, the heat, the embers under the grilled food and the kind of food can ultimately combine to produce damaging reactions. HAAs are produced mainly by searing or grilling protein-rich foods such as meat and fish at temperatures over 150 degrees Celsius. PAHs are produced by burning fat, when it smokes - especially when fat from the meat or oil from the marinade drips onto the embers or the heating element. The smoke that's produced carries the PAHs to the surface of the food being grilled.
Barbecuing foods can also produce acrylamide, a chemical that can harm your health. How can that be prevented?
Acrylamide is produced mainly by deep-fat frying, baking or roasting food rich in starch - essentially potato products, baked goods and cereal products. Because there's no starch in meat, fish and most vegetables, the formation of acrylamide when barbecuing them plays a minor role. To prevent its formation as much as possible, make sure that products containing starch that lend themselves to grilling, such as potatoes and bread, don't get cooked too long or at too high a temperature, and cut off any scorched or burnt areas liberally.
What meat is healthiest for a barbecue?
Lean meat such as cutlets or chops. To keep it from drying out, coat it with marinade containing oil, which you then wipe off before putting the meat on the grill. Spare ribs are well-suited to barbecuing, because their meat is neither too lean nor too fatty. Firm fish such as salmon, trout or tuna are suitable as well. To keep the fish from falling apart, wrap it in aluminum foil. In addition to meat and fish, potatoes and various kinds of vegetables and fruit are good to grill - for example, bell peppers, corn on the cob, tomatoes, onions, bananas and pineapple.
Are their foods that you probably shouldn't barbecue?
Cured or processed meat and sausages such as raw and cooked ham, bacon, cured pork,frankfurters and hot dogs don't belong on a grill. The nitrite contained in the curing salt reacts with secondary amines from the meat. That can produce carcinogenic nitrosamines.
Antje Gahl is a nutritionist who works at the DGE, the German Nutrition Society.
The interview was conducted by Dorothee Grüner