We all snack. Frustratingly, however, there's a lot of gray area around the term "snack" — especially when it comes to choosing a healthy one.

Some snacks you know are healthy. Others you know definitely aren't (I'm looking at you, hot fries!). But mostly, there are those snacks that you think are healthy but wouldn't be surprised to find out they aren't — like that bag of trail mix in your pantry.

Nathalie Sessions, wellness dietitian at Houston Methodist Wellness Services, says that one of the major tricks to snacking healthily is to limit added sugars — which are, unfortunately, extremely prevalent in most packaged and processed snack foods.

"Since added sugars sneak their way into almost every packaged or processed food in the snack aisle, you may be better off building your own snack that you know has limited added sugar," recommends Sessions.

Next time you're shopping for healthy snacks, skip the prepackaged trail mix and build your own using Sessions's recommendations below.

(Download How to Make a Healthy Homemade Trail Mix infographic)