"Just because a bar has protein in it does not mean it's nutritious," says Melanie Warner, author of Pandora's Lunchbox: How Processed Food Took Over the American Meal. In fact, many protein bars aren't much better for you than a Snickers. They're chock-full of sugar and saturated fat with a little protein added in, usually in the form of a highly processed powder derived from soy or milk. "These powders offer no nutritional benefits beyond the protein, which most of us get enough of from our diets anyway," says Warner. To find a bar that's actually healthy, "look for ones that have whole ingredients that haven't been broken down, whether that's oats, nuts, or dried fruit," Warner suggests. "These ingredients provide a well-rounded complex of nutrition beyond just the protein."
Or skip the protein bar altogether. "A peanut-butter sandwich on whole-grain bread is a great substitute for a bar," says Joan Salge Blake, RD, a health sciences professor at Boston University and spokeswoman for the Academy of Nutrition and Dietetics. "It travels well and costs less than 25 cents."