"For cancer, in particular, nutrition probably accounts for about 30 percent of all cancers," said Dr. David Heber, an endocrinologist at UCLA's Center for Human Nutrition.
Orange foods like carrots, sweet potatoes and pumpkins contain beta carotene, which may prevent skin cancer. Dietitian Susan Bowerman says less is more when preparing these classics. Just add a little balsamic vinegar and roast your sweet potatoes.
"When you roast sweet potatoes, it brings out that natural sweetness. They caramelize," said Bowerman.
Then there are red foods. Tomatoes have lycopene, which may prevent prostate and breast cancer. But don't store them in the fridge.
"When tomatoes sit out at room temperature, they actually make more lycopene," said Bowerman.
Broccoli contains a compound that boosts the body's protective enzymes and flushes out cancer-causing chemicals. Garlic has allyl sulfides, which help kill cancer cells naturally.
"You have to crush the garlic first before you cook it because if you cook it first, you kill the ability of this substance to be helpful," said Heber.
And of course, don't forget the turkey. It's a healthy holiday meal staple.
"Turkey breast is actually lower in fat than chicken breast," said Heber.
Experts say women should aim for meals with no more than 400 calories, and no more than 500 calories for men.