"Cooking meats at high temperatures creates chemicals that may increase the risk of cancer," says Colleen Doyle, M.S., R.D., Nutrition and Physical Activity Director for the American Cancer Society (ACS).

Chemicals called heterocyclic amines (HAs) are created by the burning of amino acids and other substances in meats cooked at particularly high temperatures and that are particularly well-done. Formation of HAs occurs in grilled and barbecued meat as well as broiled and pan-fried meat.

"Also, there is some concern fats from the meat dripping onto coals create additional chemicals in smoke that may land back on the meat," she says.

Of greatest concern to researchers are chemicals called polycyclic aromatic hydrocarbons (PAHs), which have been linked to cancer for more than 200 years. Several of the forms of PAH found in cooked meat have been shown to cause cancer in laboratory animals. The effect grilling meat has on cancer risk in humans, however, is still under investigation.

"Still, enjoying grilled meat occasionally, especially lean meat, likely won't significantly increase one's cancer risk," Doyle says. "Taking into account the following tips will help to ensure the healthiest grilled meals possible."

• Choose lean cuts of meat and trim excess fat from meat;
• Line the grill with foil and poke small holes in the foil so some fat can drain down but not all the smoke can come back onto the meat;
• Avoid charring meat and don't eat any part that is especially burned and black;
• Pre-cook meat a bit inside the house then drain away the juices before putting the meat on the grill; and
• Watch portion size; aim for a three-ounce portion.

Doyle also advises people to make a mental adjustment about barbecues. Instead of treating meat as the main attraction, view it as a side dish. Many of the chemicals created when meat is grilled (i.e., burned) are not formed during the grilling of vegetables or fruits, she says.

"A really good idea is to serve that grilled meat with a variety of fruits, vegetables and grains, and really make those the main event," she says. "While you're grilling the meat, it's a good idea to throw some vegetables on the grill. There are a lot of colorful, wonderful vegetables that grill up really nicely. Red, yellow and green peppers, yellow squash, mushrooms, onions, corn, potatoes ­ all of these make some great colorful and healthy additions to your plate."