Koff said first ask yourself what's the bar used for? A snack should average 125 calories, but double that number and more if your bar is replacing a meal.
Bars prior to exercise are better if they're lower in protein, fat and fiber, as those components can slow you down or even nauseate you during exercise. Those same nutrients are perfect if you are looking for a bar to sustain you for a while.
A meal bar can have 10 grams of protein and five or more grams of fiber, as fiber helps regulate blood sugar and slows digestion.
When it comes to carbohydrates, go for about 15-20 grams of carbohydrate per 100 calories, and know where the carbs are coming from.
"If your bar has fruit or dried fruit in it, that's providing sugar, if your bar has grains in it, that's providing sugar," Koff said.
And, of course, many add sugar as well. Often times, there's more sugar or carbohydrate in a bar than needed, so check the facts.
When it comes to bars with sugar alcohols or unnaturally occurring fiber? Koff said they may wreak havoc on your digestive system and may not give your body what it needs for optimal health.
Dietitian Patricia Bannan says soy protein isolate strips some goodness.
"You don't get the omega-3s, you don't get the fiber. It's like any processed food, so you're taking the nutrients out of it," Bannan said.
Experts like Soy Joy, which uses whole soy, Perfect Food and Pure Food containing natural fiber, fat, protein, vitamins and minerals through non-synthetic ingredients.
Pure food takes an organic, gluten-free, raw and vegan approach as well, while Gnu Foods kicks up the fiber for satiety, offering almost 50 percent of your daily needs.