Grilling versus baking meat: does the cooking method matter?

This page is for anyone who wonders whether grilling meat raises cancer risk more than other ways of cooking, such as baking. It explains which chemicals form at high heat, what the evidence in people shows, and simple ways to cut your exposure.

Two families of compounds are at the center of this question, and they form in different ways.

Heterocyclic amines, or HCAs, form at high temperatures. They form when amino acids react with sugars and with creatine or creatinine. Amino acids are the building blocks of proteins. Creatine and creatinine are substances found in muscle.

Polycyclic aromatic hydrocarbons, or PAHs, form differently. They develop when meat drippings fall onto a heat source and ignite, and through smoking processes. The smoke rises, coats the meat, and the compounds go with it.

Both are described as mutagens, meaning they can cause changes in DNA.

NCI's summary is clear that heat and duration drive this. High-heat techniques generate the most HCAs and PAHs, including grilling over open flames, cooking above 300 degrees Fahrenheit, and long cooking times.

Well-done, grilled or barbecued meats carry particularly high concentrations.

So on the narrow chemistry question, grilling over flames does produce more of these compounds than gentler methods. The charred crust and the flare-ups are exactly where the PAHs come from.

The chemistry is settled. The health consequence is not, and NCI does not pretend otherwise.

Animal studies show cancer developing. Human population studies have yielded mixed results. Some research associates high consumption of well-done, fried or barbecued meats with increased colorectal, pancreatic and prostate cancer risks. Other studies found no association.

NCI's overall summary of the human evidence is that results remain inconclusive.

Something that forms mutagens in a laboratory has not been shown, in people, to reliably produce cancer at the amounts a typical diet delivers.

That is an uncomfortable answer if you wanted a rule to follow. It is the accurate one, and it should shape how much weight you give this compared with things that are far better established.

Because reducing exposure is easy and costs nothing, NCI does suggest ways to do it:

• Avoid direct flame contact and prolonged cooking
• Microwave meat before finishing it at high heat
• Flip meat frequently during cooking
• Remove charred portions

Turning meat often is the one people find most surprising. It keeps any one surface from sitting at maximum temperature long enough to build up as much.

Microwaving first is the same logic. It gets the inside cooked so the outside spends less time on the grill.

The human evidence here is uncertain. The honest scientific position is that human studies have not agreed.

If you enjoy grilling, the reasonable response is not to give it up. It is to scrape off the burnt bits, turn the food more often, keep the flames from licking the meat, and get on with your life.

And if you are cooking for someone in treatment, the priority is almost always different: getting enough food in, in a form they can face. A barbecue that someone actually eats beats a theoretically optimal meal that goes cold on the plate.

Diet and cancer coverage has a way of making every item on your plate feel like a decision with stakes. Cooking method is a good example of how to keep such findings in their place.

Start with what is actually established. Here, the chemistry is: certain compounds form at high heat, and more of them form on charred, flame-grilled and well-done meat.

Then ask what the human evidence shows. In this case, mixed results, with the overall picture described as inconclusive.

Then ask what the suggested change costs you. Turning meat more often and cutting off the burnt edges cost nothing at all. That makes them easy to adopt even while the science remains unsettled.

That last step is the practical one. Where a possible risk is uncertain but the countermeasure is free and harmless, taking it is reasonable. Where a countermeasure would mean eating less, spending more, or worrying constantly, uncertainty is a good reason to wait for better evidence.