Hot afternoons and long weekends with friends, drinks and a BBQ, the epitome of an Australian summer.
The backyard BBQ is an iconic Aussie summer event, and for many Australian’s the BBQ is also a staple cooking method throughout the year. Barbequing tends to give meat and vegetables a smoky flavour that can’t be replicated elsewhere. It’s almost a must that Barbequed meat have a blackened charred look about it. My mum’s favourite saying when I complain about burnt bits ‘it’s not burnt, it’s Barbequed!’
But is it possible we are taking the char too far?
Could the trusty summer BBQ could actually be harmful to your health?
Burnt Meat and Cancer
Two carcinogenic (cancer causing) compounds are formed when meat, poultry and fish are cooked at high temperatures, polycyclic aromatic hydrocarbons (PAHs) and heterocyclic amines (HCAs). These are the compounds is question when studying the effect of barbequed meat on cancer risk.
The type of meat and cooking method determines how much of these compounds are produced. Grilled, barbequed and well-done meats are thought to contain the highest amounts of PAHs and HCAs. (1)
What is less understood, is the long-term effects of ingesting these compounds regularly. Also uncertain is whether we actually eat enough of these compounds to increase the risk of certain cancers.(2)
In observational studies, researchers compared dietary intakes of over-cooked and barbequed meats and the incidence of cancer. A positive link between high intakes of these meats and cancer has been seen. Observational studies can make it difficult to pinpoint the exact causative agents involved. This is due to a number of other factors also being in play. For example, it is likely that people who eat less meat also eat more vegetables and are perhaps more likely to engage in other healthy lifestyle activities such as exercise. Both of which could potentially lower cancer risk.
PAHs and HCAs are known to be carcinogenic in mice and animal studies. However, as humans are not mice it is possible we may process these compounds differently. Secondly, in these studies, the amounts of PAHs and HCAs given to the mice far exceeded what would be consumed as part of a normal diet.
In a study of 29,361 men, a diet high in well-cooked and charred meat was positively linked with an increased risk of prostate cancer. (1)
A 2017 study compared the results from multiple studies (a meta-analysis) and showed dietary intakes of both PAHs and HCAs were linked to an increased risk of colorectal cancer. (3)
In contrast, another large scale study with a 14 year follow up, found no significant relationship between well done meat and the incidence of colorectal cancer.(4)
It is also thought that some people are genetically more susceptible to the harmful effects of PAH’s and HCA’s.
Tips for Getting BBQ Flavour Without the Burn
To completely avoid PAH’s and HCA’s you would need to stick to other cooking methods such as baking, boiling and microwaving. Although these methods often lead to bland tasting food.
To reduce the amount of PAH’s and HCA’s produced while still enjoying your BBQ here are a few tips.
Contrary to popular belief you can still achieve that smoky goodness without incinerating your food. Most of the charred and BBQ flavour comes from the smoke. Fat dripping into coals produces smoke, when food is exposed to that smoke you can achieve a smoky flavour without burning the meat. Keep in mind this smoke does still contain PAH’s, however it is thought that the combination of well cooked meat and smoke is more reactive than the smoke alone.
– If your BBQ has a hood put the hood down to trap the smoke.
– Continually turning meat prevents burning and reduces the amounts of HCAs produced.
– Try blanching sausages in boiling water prior to barbequing. This will result in a more even cook and you won’t need to burn the outside to ensure the middle is cooked.
– If you have a higher shelf/rack in the BBQ put your sausages or meat there while cooking other things, this will increase the amount of smoke coming in contact with the meat and enhance the flavour.
– Salt the outside of your steak to get the caramelisation without too much char.
There are some conflicting results regarding the effects of burnt meat, and currently there are no official guidelines in regard to the cooking methods of meat.
However, it appears likely that over cooked meat can potentially increase the risk of certain cancers. To be on the safe side it is best to limit your intake of charred and well-done meats.
Happy summer barbequing, don’t forget the salads!
1. Cross AJ, Peters U, Kirsh VA, Andriole GL, Reding D, Hayes RB, et al. A prospective study of meat and meat mutagens and prostate cancer risk. Cancer Research. 2005;65(24):11779-84.
2. Turesky RJ. Formation and biochemistry of carcinogenic heterocyclic aromatic amines in cooked meats. Toxicology letters. 2007;168(3):219-27.
3. Chiavarini M, Bertarelli G, Minelli L, Fabiani R. Dietary Intake of Meat Cooking-Related Mutagens (HCAs) and Risk of Colorectal Adenoma and Cancer: A Systematic Review and Meta-Analysis. Nutrients. 2017;9(5):514.
4. Le NT, Michels FAS, Song M, Zhang X, Bernstein AM, Giovannucci EL, et al. A prospective analysis of meat mutagens and colorectal cancer in the Nurses’ Health Study and Health Professionals Follow-up Study. Environmental health perspectives. 2016;124(10):1529.