How healthy (or not) certain foods are—for us, for the environment—is a hotly debated topic among experts and consumers alike, and there are no easy answers. But when Prevention talked to the people at the forefront of food safety and asked them one simple question—“What foods do you avoid?”—we got some pretty interesting answers. Although these foods don’t necessarily make up a "banned” list, as you head into the holidays—and all the grocery shopping that comes with it—their answers are, well, food for thought:

The expert: Fredrick vom Saal, PhD, an endocrinologist at the University of Missouri who studies bisphenol-A

The problem: The resin linings of tin cans contain bisphenol-A, a synthetic estrogen that has been linked to ailments ranging from reproductive problems to heart disease, diabetes, and obesity. Unfortunately, acidity (a prominent characteristic of tomatoes) causes BPA to leach into your food. Studies show that the BPA in most people's body exceeds the amount that suppresses sperm production or causes chromosomal damage to the eggs of animals. "You can get 50 mcg of BPA per liter out of a tomato can, and that's a level that is going to impact people, particularly the young," says vom Saal. "I won't go near canned tomatoes."