Picking healthy snack foods can feel pretty confusing. There are thousands of items to choose from at the grocery store, yet it's hard to come up with ideas for healthy and satisfying snacks.

You want something that packs in nutrients and keeps you feeling full if you're out for a hike or on the go all day. We put two snack foods head to head to find out which is healthier: this or that? Granola bars or trail mix?

The Winner: Trail mix, as Joyce Hendley first reported for EatingWell.

Both of these snacks have such healthy halos, they almost gleam-but if you choose wisely, trail mix-sometimes called gorp-tends to have a little more real health value.

Here's where the differences lie:

Trail Mix:If you choose trail mix instead of a bar, you can see exactly what you're getting. Be sure to pick a mix that contains more of the good stuff like nuts, seeds, dried fruits and whole-grain cereals-and less of the chocolate chips, yogurt-covered raisins and candy pieces (which are tasty but not as healthy). Better yet, make one yourself-try these easy recipes for starters: Crunchy Cereal Trail Mix and Homemade Trail Mix

Granola Bars: Granola bars might start with some healthy ingredients like whole-grain oats and nuts, but the binders that hold them together can add a lot of unwanted ingredients. Added sweeteners, such as high-fructose corn syrup, as well as starches and gums weigh down the beneficial stuff in that bar and add empty calories.

Another problem: enriched (i.e., white) flour or refined cereals, like puffed rice, might be high on the ingredients list and don't have the beneficial fiber of whole grains like oats.

Granola bars vary widely, so it's important to scan labels: Consumer Reports found that calories range from 90 to 270 per serving; sugars from 2 to 20 grams; fiber from less than 1 gram to 9 grams.

Not So Satisfying: Some highly processed "high-fiber" granola bars might be pumped up with "functional fibers" like cellulose fiber (derived from wood pulp) or inulin (or chicory extract). These can help get your fiber numbers up, but might not deliver all the benefits of fiber that naturally occurs in foods.

If you are going to choose a granola bar, look for these healthy options in the store or make your own healthy bars with these recipes.