It's that time of year again. Hot weather sets picnic fever - and the nation's barbeque grills - ablaze; in fact, according to the Hearth, Patio and Barbeque Association, 4 out of 5 American households will fire up backyard grills this summer.

Today, in time for the first day of summer, experts at the American Institute for Cancer Research (AICR) issued their yearly advice for healthy grilling. This year, that advice is bolstered by new evidence in a just-published report on the prevention of colorectal cancer.

As part of its groundbreaking Continuous Update Project, AICR and the World Cancer Research Fund released a report on May 23 that added recent research findings to its growing database on the role of diet, physical activity and weight in colorectal cancer risk, re-evaluated the combined evidence, and updated the judgments of the AICR/WCRF 2007 Expert Report.

One finding of the new report, that diets high in red and processed meat are a convincing cause of colorectal cancer, made international headlines. Today, AICR experts placed that finding in a useful context for devotees of the backyard barbeque.

"Two aspects of the traditional American cookout, what you grill and how you grill it, can have a role in raising risk for cancer," said AICR spokesperson Alice Bender, MS RD. "Big portions of red and processed meat are a well-known concern with respect to colorectal cancer. And although the evidence on the link between grilling itself and cancer risk is less strong, it only makes sense to take some easy cancer-protective precautions."

Bender noted that when any kind of meat, poultry or fish is cooked at high temperatures, especially when well-done or charred, cancer-causing compounds called heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs) form. These substances can theoretically damage DNA in ways that make cancer more likely.

"The good news is that there are four simple strategies you can use to make allowances, manage risks, and grill more safely," said Bender.

1. Get the Red (Meat) Out, Add Other Colors

- Focus first on grilling colorful vegetables and fruits, and cut back on the amount of red and processed meat on your cookout menu. Plant foods contain a variety of naturally occurring compounds called phytochemicals, many of which provide their own anti-cancer protection.

- Vegetables like asparagus, onions, mushrooms, zucchini, eggplant and corn on the cob are favorites, because grilling brings out flavors that even the pickiest eaters enjoy. Cut into chunks for kabobs, cook in a grill basket, or toss with a small amount of olive oil and grill whole.

- Cut fruit before putting it on the grill: apples, peaches and pears can be halved and bananas split lengthwise. Use fruit that is about a day or two away from being completely ripe so it retains its texture. If you brush fruit or the grill with a bit of oil, it won't stick, and remember to watch closely so it doesn't get overdone. Serve as is, with a sprinkle of cinnamon or a dollop of plain frozen yogurt.

2. Marinate the Meat

- If you choose to grill meat, mix it up: Try chicken or fish instead of sticking with burgers and hot dogs. Whatever meat you choose, start by mixing up a marinade with some of your favorite herbs along with vinegar or lemon juice. Keep the meat marinating in the fridge while you prepare the sides. Marinating meat has been shown to reduce the formation of HCAs. Precisely why marinades are protective is still under investigation; some evidence points to the acids (vinegar and citrus) or the antioxidant content. Even just 30 minutes in the marinade can help.

3. Partially Pre-cook

- You can do this in the microwave, oven or stove to help reduce the amount of time the meat sits on the grill exposed to high heat. To ensure safe food handling, just be sure to put the partially cooked meat on the preheated grill immediately to complete cooking.

4. Go Slow and Low

- To reduce the amount of HCAs and PAHs that end up in, and on, the meat, slow down the cooking time with a low flame and keep burning and charring to a minimum. More tips: cut off any visible fat (to reduce flare-ups), cook food in the center of the grill and move coals to the side (to prevent fat and juices from dripping on them) and cut off any charred portions of the meat.

American Institute for Cancer Research (AICR)