Breakfast cereal
Something like mixed nuts doesn’t have many ingredients—maybe nuts, sea salt, and one or two more things. So you probably won’t find a ton of variation between brands, says Keri Gans, RD, author of The Small Change Diet. Breakfast cereals, on the other hand, can have ingredients lists several inches long. “I’d be looking closely at how much added sugar is in it? How much fiber?” she says.