'Fattening' airplane snacks slammed by transportation secretary: 'Full of butter, sugar and crap'

"I would love a little healthier snack on the airplane," Duffy told Blaze News.

"[It would be much better] if I didn't get the really fattening cookie full of butter, sugar and crap," he added. "Or that little snack pack of pretzels."

Erin Palinski-Wade, a New Jersey-based dietitian, told Fox News Digital that pretzels and cookies "won't ruin your health." She added, though, that the refined starch, sodium and added sugar in them can spike energy levels quickly.

"Some airlines offer chocolate-covered quinoa, which can be a better alternative, as it provides a boost of protein and fiber to keep blood sugar and appetite steady," she said.

"Freeze-dried fruit is shelf stable and a great way to boost fiber and antioxidants without worry of spoilage," the dietitian suggested. "Dry-roasted chickpeas can be a crunchy snack offering that provide a similar nutrition profile to nuts (with protein and fiber), without the allergy risk to sensitive passengers."

Protein bars, nuts, beef jerky and lentil crisps are all tasty snacks that can travel well, she added.

She added that a little planning goes a long way, particularly for passengers with diabetes or heart conditions.

"Don't just grab whatever's free on the plane," she said. "This small change can be the difference between feeling steady all day and riding a blood sugar roller coaster mid-flight."

Brandon Blewett, a travel aficionado and author of the book "How To Avoid Strangers On Airplanes," told Fox News Digital he always keeps protein bars in his bag. He agreed that hard-boiled eggs and jerky are also good snacks to pack on the go.

"Just be respectful of everyone around you and avoid scraping the container, as that sound can get you put on an unofficial no-fly list," he joked. 

"Otherwise, I go for protein bars, jerky, hard-boiled eggs, pre-cut fruit or vegetables - or airport 'protein packs.'" 

"Airports often have Chick-fil-A, and the grilled chicken sandwich or grilled nuggets are great options," he suggested. "Their fruit or vegetable sides are also clutch."

"If I am hungry and undecided, I walk the entire terminal to see every option first. You get some steps in and make a better decision," Blewett said.

"Walking with your backpack on is perfectly fine as long as it is not overloaded. It adds a little bit of extra effort, which is never a bad thing on a travel day."

Reuters contributed reporting.