Hard-and-fast food rules are made to be broken. But some common foods are seriously bad for you. "It doesn't mean you'll get sick, get cancer, or die if you eat a dangerous food once," says Nneka Leiba, deputy director of research at the Environmental Working Group (EWG), which ranks foods' safety. "But there are certain foods you should avoid as much as possible if you have a choice."
With that in mind, do your best to steer clear of the foods that scare registered dietitians.
"The reality is that American cheese is not 'cheese' at all," says Beth Warren, a New York-based registered dietitian and the author of Living a Real Life With Real Food. Depending on the brand, "it's a factory creation of a cheese-like food made from a blend of milk fats, solids, some whey protein, emulsifiers, and food coloring." It's high in sodium, and so high in fat that one regular slice more closely resembles high-fat meat than anything considered dairy, Warren adds.
Step away from the deli counter. Processed meats in the U.S. such as ham, salami, hot dogs, and bacon aren't just full of unhealthy fats. They can have up to 400 percent(!) more sodium and 50 percent more preservatives than unprocessed red meats. The worst part: Some contain nitrites and nitrates, chemical additives that have been linked to various cancers, but are still used to enhance color, promote taste, and prevent spoilage. These ingredients must be listed on food labels, so look out for them and opt for meats that don't contain them.