Bake tomatoes for younger skin and cancer protection.  Compared with fresh tomatoes, cooked tomatoes (and products like pasta sauce) contain more lycopene, a powerful antioxidant.  Research suggests lycopene may guard the skin against damage from the sun's UV rays.  Baking tomatoes makes them healthier and more versatile.

Roast omega-3-rich fish for a slimmer waistline.  Roasting a fatty fish, such as salmon, with a bit of olive oil doesn't increase its fat content.  When researchers fried the fish, it absorbed the olive oil, increasing fat content by 10% (and adding unnecessary calories).

Crush garlic for healthier arteries.  Crushing the cloves and letting them stand for up to 30 minutes before heating them activates and preserves the garlic's heart-protecting compounds.  Cooking uncrushed garlic for as little as 6 minutes can completely suppress its protective strength.   

Steam broccoli for reduced cancer risk.  Steaming increases its content of gulcosinolates, compounds that fight cancer; other cooking techniques, like frying, reduce them, according to new research.

Slow cook meat for preventing inflammation linked to diabetes and heart disease.  When meats are cooked in liquid at moderate heat, they develop fewer cell-damaging compounds known as as AGE (advanced glycation end products) than when they are broiled or grilled  Researchers say that switching to "wet" cooking methods can reduce AGE intake by 50%.