When Bear Grylls is taping his TV show "Running Wild," he and his celebrity co-adventurers have to prepare a cook-what-you-can-find meal under the most rugged circumstances. He's terrorized Julia Roberts, Roger Federer, Zac Efron, even Barack Obama.

You can bet they hope they won't have to grill up and devour a hairy spider, like Bear does on a YouTube video he shot in 2010.

But for you backyard chefs, the scariest thing about your bare grills isn't what you're cooking, but your cooking technique.

Grilling meat at high temperatures can produce cancer-causing chemicals called heterocyclic amines (HCAs), and dripping fat and juices that cause smoky flare-ups deposit toxic polyaromatic hydrocarbons (PAHs) on the food.

Luckily, to avoid these health hazards you don't have to replicate Roger Federer's "Running Wild" dinner of a half-gnawed frozen fish carcass retrieved from an icy pond.

Instead, to reduce grilling risks:

• Trim the fat and remove poultry skin to reduce smoky fires; don't char meat.

• Use a gas grill for temperature control, keeping temps below 325 F.

To further reduce HCAs and PAHs:

• If you're rushed, marinating meats for 15 minutes in olive oil and vinegar will do the trick.

• Even better is to marinate meats for at least 60 minutes in an acidic mixture of wine or beer, vinegar, and/or orange or pineapple juice. One study found that a six-hour soak in red wine slashed production of two carcinogenic chemicals by 40 percent and 80 percent.