Asked by: Rachel Williams, Shropshire
Meat contains creatine, an organic acid that helps to supply the energy used by muscle cells. When you cook meat, a chemical reaction turns creatine into a group of compounds called heterocyclic amines (HCAs) and there is some evidence that these compounds cause cancer in high concentrations.
Frying and grilling meat will produce some HCAs but barbecues tend to be much hotter, and worrying about underdone meat means that many of us tend to cook until everything is well charred, so the level of HCAs is much higher.
Also, unlike grilling, a barbecue heats the meat from below. As the fat drips onto the hot coals it burns, and the smoke rises up and coats the meat. This smoke contains lots of polycyclic aromatic hydrocarbons (PAHs) from the partially burned fat. PAHs are another group of chemicals that are known to cause cancer.
But so far most of the studies linking HCAs and PAHs to cancer have been in the laboratory, using rats and very high doses. Most people don’t eat barbecue food often enough for the health risk to be measurable. Even if you spend every Saturday afternoon in the sunshine drinking beer and eating burgers, the alcohol and the cholesterol are probably hurting your health a lot more than the HCAs and PAHs.
But if you are worried, a study reported in the Harvard Health Letter suggests you can reduce the level of these carcinogens by 90 per cent if you pre-cook your meat in the microwave for two minutes and then just scorch it briefly on the barbecue for flavour.
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