Many people would be surprised to hear that barbecuing carries potential cancer risks. But each year, the American Institute for Cancer Research publishes guidance for “cancer-safe grilling”, cautioning consumers to avoid two types of compounds that have been tied to cancer.
These compounds, called polycyclic aromatic hydrocarbons and heterocyclic amines, get generated when food, especially meat, is cooked on a barbecue. They have not been proven to cause cancer in people, but lab studies have shown they alter DNA in a way that could lead to cancer.
"Polycyclic aromatic hydrocarbons are formed when any kind of organic matter," primarily fat that drips off meat and down into the barbecue grates, "gets burned, because the carbon inside is being combusted in the flames, and those hydrocarbons get carried up in the smoke," says Rashmi Sinha, senior investigator in the Division of Cancer Epidemiology and Genetics at the US's National Cancer Institute. The resulting smoke can envelop the meat and coat it in the potentially carcinogenic compounds.
The black char we've all seen on barbecue grates and grilled food? That's the heterocyclic amines, or HCAs, which occur when high temperatures meet muscle meat, which includes red meat (pork, beef, lamb, goat), poultry (turkey, chicken) and fish. "Grilling – or even pan-frying – at these high temps causes amino acids found in the meat to react with another substance found in meat called creatine," says Colleen Doyle, managing director of nutrition and physical activity at the American Cancer Society and a registered dietitian. Creatine is found only in muscle meat.
“It’s the reaction of those amino acids and the creatine that form the HCAs, which is why we don’t see HCAs formed when grilling asparagus, squash, peppers and other vegetables.”
As with most lifestyle choices related to dialling up or down one’s cancer risk, the dose makes the poison. Which means if you’re barbecuing once or twice a year, don’t sweat it.
But if you plan to barbecue often – once or twice a week throughout the summer, say (presumably the lack of warm weather in Ireland doesn’t put you off) – experts suggest taking some small steps to make a big difference in lowering your exposure to these compounds.
1. Think outside the burger
Barbecue fish, seafood, poultry or plant-based foods rather than red meat and especially processed meats like hot dogs; the World Health Organisation considers processed meats a carcinogen and red meat a probable carcinogen. While HCAs are still formed while grilling fish and seafood, Doyle points out that you typically don’t have to cook seafood as long as beef and chicken, which reduces the accumulation of the compounds.
2. Marinate first
Research suggests that marinating for at least 30 minutes can reduce the formation of HCAs on meat, poultry and fish. The reason for this is not entirely clear to researchers, but one possibility is a kind of shield effect. "If you put a barrier of basically sugar and oil between the meat and the heat, then that is what becomes seared instead of the meat," says Nigel Brockton, vice president of research at the American Institute for Cancer Research. It also makes your meat more flavoursome.
3. Make produce the star
Many kinds of fruits and vegetables are actually protective as far as cancer risk, and they don’t form HCAs when grilled. Several experts recommend using meat as a condiment. Think of alternating cubes of chicken with peppers and onions or peaches and pineapple on a skewer, for instance. This trick, which also works when pan-frying, reduces the surface area of meat exposed to the hot surface, Brockton explains, since the meat is also touching other ingredients throughout the cooking process.
4. Leverage herbs and spices
According to Brockton, cooking your meat with herbs, spices, tea, chilli peppers and the like – ingredients with phenolic compounds – can be a helpful approach because “it seems they quench the formation of the potentially carcinogenic compounds because of the antioxidant properties of those ingredients”.
5. Be mindful of the smoke itself
Try to minimise how much smoke you’re breathing in, the Harvard TH Chan School of Public Health recommends as part of a helpful resource on healthy summer picnic practices.
6. Avoid char
The black, crispy crust that you often see on the bony edges of ribs or steak is more likely to contain a higher concentration of potentially carcinogenic compounds. Doyle also recommends cleaning the barbecue grates ahead of time to remove any previously generated char.
7. Cut time on the barbecue
“The longer you cook something, the longer the chemical reaction is happening, the higher the amount of HCAs are formed,” Brockton says. If you partially precook your meat, such as by baking or cooking in the microwave, the layer of HCAs that gets formed won’t be as thick. The same goes for meat cut into smaller pieces, such as with kebabs, because it cooks faster. Grilling in foil can also help protect the food from smoke and speed up the cooking time, according to the Harvard resource on healthy picnics.
8. Select hardwoods instead of soft woods
“Types of wood can influence HCA formation,” Doyle says. “Hardwoods, such as hickory and maple, and charcoal all burn at lower temperatures than soft woods, such as pine. Cooking with wood that burns at a lower temperature is desirable.”
9. Reduce fuel for the fire
To minimise your exposure to polycyclic aromatic hydrocarbons, experts recommend selecting leaner cuts of meat or trimming any visible fat, which can lower the amount that drips down through the grates and comes back up in the smoke. To minimise dripping, Doyle suggests not piercing your meats while they’re on the grill.
10. Flip often
According to guidance from the National Cancer Institute, fewer HCAs are formed if you turn meat over frequently while cooking it on high heat. – New York Times
