Great grilling - health risks of polycyclic aromatic hydrocarbons; includes related articles

Great Grilling

I love grilled fish. My father caught--and my sister grilled--the fish we served at my wedding. It truly was the best fish I have ever eaten. And though I don't barbecue at home, my family and I enjoy grilled food when we eat out...which might explain why I approached the question: "Does grilled food pose a cancer risk?" with more than a little trepidation.

It also might explain why I was relieved to find that while grilling does add some unwanted chemicals to food, there are ways to minimize them.

These days, grilling is a lot more than tossing a few steaks on the old barbecue. Whether it's "flame broiled" burgers at Burger King or Brochettes de Crevettes et Coquilles de St. Jacques at New York's four-star Le Cirque, grilling is enormously popular.

"I can't say it's a revolution, since it's been around since cave-man days," says Scott Allmendinger, food editor of Restaurant Business magazine. "But it's a very big trend."

PAHS: WHEN THE FAT HITS THE HEAT

Any type of cooking (and that includes grilling) makes most food taste better. It also kills disease-causing organisms, destroys toxins, and increases digestibility.

There's a price to pay, though. When we grill meat (that means beef, pork, lamb, poultry, or fish), a few dozen chemicals are formed. Some of them are suspected of causing cancer.

The first step in avoiding risky chemicals in grilled meat is to understand how they can form.

Whenever fat drips onto a flame, heating element, or hot coals, chemicals called PAHs (polycyclic aromatic hydrocarbons) form. The PAHs rise with the smoke and are deposited on the surface of the food. They can also form directly on the food when it is charred.

As early as 1775, PAH-containing soot was linked to cancer of the scrotum in chimney sweeps. Today, grilled meat is the major source of PAHs in our food.

Of the more than 100 PAHs found in the environment, at least 18 have been identified in cooked food. Depending on which experts are looking at the data, either five or 12 of the 18 cause cancer in laboratory animals.[1,2] (The rest cannot yet be classified as cancer-causers or not.) The key to preventing PAHs from forming is to stop the fat from dripping onto the heat source. That's why broiling (with the heat source above the food), any type of cooking in a pan, stewing, and baking result in few if any PAHs. That's also why grilled fatty meats like pork ribs contain more PAHs than leaner cuts.

HAs AREN'T FUNNY

While PAHs seem to be limited to grilling or barbecuing, another group of risky chemicals, heterocyclic amines (HAs), occurs more frequently in broiled and pan-fried meats. HAs are formed from the burning of amino acids and other substances that are in all meats.

In general, the hotter the temperature and the more well done the meat, the more HAs.[3]

Unfortunately, researchers don't yet know enough to determine if HAs in broiled and other meats pose a greater risk than PAHs in grilled meats.

(To be on the safe side, though, you can reduce the level of HAs, no matter how you're going to cook your meat, by pre-cooking it in a microwave on "High" for 30 to 90 seconds and discarding the juice that collects.)

HOW MUCH RISK?

How big is the risk from PAHs? No one is really sure.

For one thing, we don't fully understand how the different chemicals in cooked meats interact.

Take CLA (conjugated linoleic acid), which is found in grilled ground beef and some dairy products.[4] In preliminary rat studies, high doses of CLA appear to inhibit cancer caused by PAHs. But scientists haven't yet determined if the amount of CLA in grilled ground beef is sufficient to neutralize the PAHs.

By our estimates, if you eat grilled fatty meats every day, you're playing with fire as far as your risk of cancer is concerned. If you eat grilled meats less than once a month (and if it's not always an untrimmed T-bone), your risk is pretty insignificant.

If you fall somewhere between these two extremes, go ahead and enjoy yourself...as long as you follow our grilling tips when you barbecue at home or eat out.

[1]Ann. Rev. Nutr. 6:67, 1987. [2]WHO, An Updating of IARC Monographs Volumes 1 to 42, Suppl. 7, 1987. [3]ISI Atlas Sci. Pharm: 222, 1988. [4]J. Agric. Food Chem. 37:75, 1989.

COPYRIGHT 1989 Center for Science in the Public Interest
COPYRIGHT 2004 Gale Group