Fruit is a great go-to snack, as it often has its own convenient (and natural) packaging. Or try making your own granola bars with gluten-free oats or packing a handful of nuts and dried fruit.
I always try to pack a meal that includes some protein, some carbs and something sweet," Koeller says. "Protein powder, instant soup or instant oatmeal are all great meals in a pinch—all you need is water!" (Just remember to check the label on prepackaged foods for hidden sources of gluten.)
Remember that detours, flight delays and other unexpected events can derail your travel schedule, so always pack an extra snack to tide you over until you reach your destination. If you end up being delayed longer than expected, look for naturally gluten-free snacks. Nuts are a filling, portable option (skip dry-roasted varieties, which may include gluten-containing ingredients), as are whole fruits, gluten-free yogurts and certified gluten-free deli meats and cheeses, which can be rolled up and eaten without bread.