Whether you’re on a road trip or grappling with a busy workday, you know this scene: You’re standing in a gas station or bodega or drug store. You’re hungry. And as you gaze up at the dizzying display of protein bars—dozens of options encased in brightly-colored, rectangle-shaped, vacuum-sealed packets, each one proudly touting the number of grams of protein it will provide and/or the number of carbs it won’t—you have absolutely no clue which one to choose. After four minutes of helpless staring, you throw up your hands, grab a bag of chips, and call it a day.

Good news: You can now save your frustrations for more important things, like football Sunday. We asked a few experts for the lowdown on what everything on those byzantine nutrition labels really means—and which protein bars you should buy (and avoid) as a result.

Quest Nutrition Bar, Chocolate Chip Cookie Dough

The numbers: 200 calories, 21 grams protein, 14 grams fiber, 9 grams fat, 1 gram sugar (0 added), 3 grams sugar alcohol

If you’re looking for a bar that will keep you full for longer, look for something chock-full of fiber and protein, suggests nutritionist Alissa Rumsey, RD. Why? Fiber takes more time to digest, which means it sticks around in the stomach for a while, which means that after eating it, you feel fuller for longer.

The Quest bar might fit that bill, but admittedly I’ve only ever consumed them one-half at a time for fear of what it may do to my insides. “High fiber content can definitely cause gas and bloating,” says Marsha Girgis, RD. “As much as I support a fiber-rich diet, it is important to ease into it to avoid discomfort.”

Another thing to note on this bar: Although it’s low in sugar, it does contain sugar alcohol—sweeteners that have fewer calories than regular sugar, notes Rumsey. These can be tough to digest, too. Put differently: Experimenting with one of those before a first date, a job interview, or your wedding ceremony is a risky proposition.

Quest Nutrition chocolate chip cookie dough protein bar (12 pack)$23

Amazon

RX Bar, Chocolate Cherry

The numbers: 210 calories, 12 grams protein, 4 grams fiber, 8 grams fat, 17 grams sugar (0 added)

These bars are as simple as they look, with the ingredients listed on the front of the packaging. “The sugar content is slightly high, but it’s naturally occurring sugar from the cherries,” says Girgis. “There are no artificial colors, flavors, or preservatives. Because of its fat, protein and fiber levels, it can definitely keep you full until the next meal”—which, if you’re lucky, won’t have to come in bar form.

RX Bar chocolate cherry protein bar (12 pack)$21

Amazon

CLIF Builder’s Protein Bar, Chocolate Peanut Butter

The numbers: 290 calories, 20 grams protein, 2 grams fiber, 17 grams sugar (17 added)

This is the kind of bar that should be reserved for athletes doing a long endurance activity. It’s got around four teaspoons of sugar, which is a nightmare for someone sitting at a desk all day, but great for a cyclist on their second hour of hill climbs. Unless your office is the seat of a very expensive bicycle, consider saving these for another day.

Clif Builders chocolate peanut butter protein bars (12 pack)$14

Amazon

Muscle Milk Protein Bar, Chocolate Peanut Butter

The numbers: 250 calories, 20 grams protein, 9 grams fiber, 2 grams sugar (14 grams sugar alcohols)

Caution: Bloating possible. While these are high in protein, they’re also packed with processed ingredients—not exactly ideal. “The best bar choice will have as much real food as possible, like nuts, seeds, and fruit,” says Keri Glassman, RD.

Muscle Milk chocolate peanut butter protein bars (12 pack)$24

Amazon

KIND Bar, Dark Chocolate Nuts & Sea Salt

The numbers: 180 calories, 6 grams protein, 7 grams fiber, 5 grams sugar (4 added)

Intuitively, it feels like these should be safe, both because of their pleasant-sounding name and also because, like RX Bars, you can see almost everything listed on the label inside the clear-wrapped packaging. Rumsey agrees, applauding the bars’ use of peanuts, almonds, and other whole, readily-identifiable ingredients. Note that these are among the lowest on the protein scale that we’re examining here, though. Consume as more of a snack and less of a this-will-hold-me-over-all-afternoon fix.

KIND Bars, dark chocolate nuts & sea salt (24 pack)$29

Amazon

CLIF Nut Butter Filled Organic Bar, Coconut Almond Butter

The numbers: 230 calories, 6 grams protein, 3 grams fiber, 9 grams sugar (7 added)

CLIF’s schtick is about making snacks for athletic types, so it’s not a surprise to see a good amount of added sugar here to fuel tired muscles during intense physical activity. Glassman praises this entrant for its organic ingredient list, and Girgis digs the real nut butter center for its healthy fats and antioxidants. “Since fat keeps you full longer, this would make for a better snack,” she says.

Clif Nut Butter Filled coconut almond butter organic energy bars (12 pack)$15

Amazon

GoMacro Bar, Oatmeal Chocolate Chip

The numbers: 260 calories, 12 grams protein, 3 grams fiber, 12 grams sugar

Gluten-free, vegan, and soy-free, this bar is made with organic sprouted brown rice and pea proteins, making it great for anyone who wants a protein supplement, but not one in which animals are involved. Bonus: All of the sugars are found naturally in ingredients like oats, vanilla, and chocolate chips.

GoMacro oatmeal chocolate chip vegan protein bars (12 pack)$35

Amazon

Gatorade Whey Protein with Almond Butter Bar

The numbers: 220 calories, 20 grams protein, 1 gram fiber, 9 grams sugars (8 added), 4 grams sugar alcohol)

Another pick aimed at people working up a considerable sweat. With half the sugar of Gatorade’s original, candy bar-esque whey bar, it’s a fine thing to reach for after a heavy lift. However, 
Girgis notes that it is also highly processed, and recommends using it as an occasional training aid instead of as an everyday supplement.

Gatorade whey protein with almond butter bars (12 pack)$18

Amazon

Perfect Bar, Almond Butter

The numbers: 310 calories, 13 grams protein, 4 grams fiber, 18 grams sugar

If you’ve ever sampled a Perfect Bar, then you know that eating one is pretty much being handed a spoon and the nut butter of your choice and being told to “go to town.” They’re filling, sure, but are also full of added sugar. Perhaps a good option when you're in the mood for something that is half-protein bar, half-grab-and-go dessert.

Perfect Bar almond butter protein bar (8 pack)$24

Amazon

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