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food for thought

Q: I’ve heard that grilled meat contains carcinogens. Is that true for chicken and fish, too? How often is it safe to eat barbecued meat?

With summer upon us, we’re heading into prime barbecue season. But depending on what you throw on the grill – and how often – you could be jeopardizing your health.

Research suggests that eating lots of grilled meat, chicken or fish increases the risk of certain cancers. And if you like your meat well-done, there may be more cause for concern.

You don’t have to resort to cooking indoors, though. In fact, broiling or pan-frying your steak is equally risky.

What matters most is the type of food you grill, what you do with it before it hits the grill and how you long you cook it.

Cooking at a high temperature – grilling, oven-broiling, pan-frying and deep-frying – creates carcinogens called heterocyclic amines (HCAs). They’re formed when amino acids (the building blocks of protein) and creatine (a natural compound in muscle meats) react at high temperatures. (Pan-frying creates the most HCAs.)

Additional cancer-causing chemicals, called polycyclic aromatic hydrocarbons (PAHs), can form when fat and juices from meat drip onto hot coals or stones. PAHs are then deposited on the surface of meat by smoke and flare ups.

Once consumed, HCAs and PHAs can damage DNA after they’re activated by certain enzymes in the body. The activity of these enzymes varies among people, influencing cancer risk associated with cooked meat.

Grilled meat and health risks

Studies in rodents have shown that exposure to HCAs and PAHs cause cancers.

Research in people, though, hasn’t turned up a definitive link between grilled meat and cancer risk.

Some, but not all, studies have tied eating plenty of well-done, fried and barbecued meat with a greater risk of colorectal, pancreatic, prostate cancer and kidney cancer. A 2016 study also linked a high intake of grilled, barbecued and smoked meat to an increased mortality risk among breast cancer survivors.

Earlier this year, researchers from Harvard University found that among more than 100,000 healthy men and women, those who ate grilled, broiled or roasted meat, chicken or fish more than 15 times a month had an increased risk of high blood pressure. So did participants who preferred their food well-done.

These studies were not randomized controlled trials; they were observational in nature and don’t prove cause and effect.

Safe grilling tips

Currently, there are no guidelines that address the consumption of foods that contain HCAs and PAHs.

The good news: There are a number of ways to substantially reduce the formation of these chemicals when you cook meat.

Marinate first

Marinating meat for at least 30 minutes has been shown to reduce carcinogen formation during grilling by as much as 99 per cent.

Ingredients in a marinade such as citrus juice, wine, beer, olive oil and fresh herbs contain antioxidants that may block the formation of HCAs and PAHs. A longer marinating time means more antioxidants will be incorporated into meat’s muscle fibres.

A marinade also acts as a barrier between meat and PAHs carried up by smoke.

Dry rubs made with olive oil, herbs and spices may also help to reduce carcinogen formation.

Reduce grill time

Cooking meat for a long time generates more carcinogens. Grill small portions of meat, chicken and fish so they cook faster and spend less time on the hot grill.

Fillets of fish cook faster than meat and chicken.

For a larger cut of meat that takes longer to cook, partially precook it in the microwave and then finish it on the grill. Research suggests that doing so can eliminate as much a 90 per cent of carcinogens.

Avoid char

For safer grilled meats, choose lean cuts (e.g., sirloin, tenderloin, flank steak, lean ground meat) and trim excess fat before cooking.

Keep a squirt bottle of water handy to control flare ups. If you do char your meat, cut it away before eating.

Flip and add flavonoids

Flipping meat often during grilling helps prevent carcinogen formation, according to research using beef patties.

Mixing antioxidant-rich blueberries or cherries (mashed) into ground meat can also help significantly reduce HCA and PAH formation.

Grill vegetables

Vegetables (and fruit) don’t form HCAs when they’re grilled. Plus, eating plenty of them is linked to cancer prevention.

Grill bell peppers, onion, mushrooms, eggplant, fennel, sweet potato, pineapple, mango and even watermelon. Tofu and bean burgers are healthy grilling choices, too.

Leslie Beck, a Toronto-based private practice dietitian, is Director of Food and Nutrition at Medcan.

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