Most of us have at least a general idea of what's good for our bodies (a fruit plate) and what's not (a king-size chocolate bar). Making smart decisions is half the battle.

The other half is knowing where hidden dangers lie. Platkin cautions consumers to be wary around anything that comes with a sauce, whether it's salad dressing, mayonnaise on a sandwich or caramel dip for your apple slices. Even an extra tablespoon can add unnecessary calories.

Also be on the lookout for packaged snack foods like chips or crackers that are probably high in sodium. "Look for things that are in their natural state," he says.

Most importantly, avoid fried food, DeGeorge says. Anything smothered in batter then dipped in hot oil isn't good for your health, even if it did at one time resemble a vegetable.

Pack for emergencies

You always pack an extra pair of underwear in your carry-on, so why not some extra healthy snacks too?

"We often underestimate the amount of time a trip can take," Platkin writes on his site. "A two-hour flight could mean four or five hours of travel."

Although liquids are restricted, most foods can be taken through security, according to the Transportation Security Administration. Platkin recommends dry cereal like shredded wheat, energy bars or cold cut sandwiches. Raw fruits and vegetables are also easy to pack and carry onboard.