Finding the perfect keto protein bar can be tough. While there a literally hundreds of low-carb, high-fat keto bars to consider, registered dietitians suggest that not all bars are created equal.

Besides looking for a bar that’s low in carbs and high in fat (so you can stay in ketosis), you also want to look for a bar that’s a good source of fiber and protein, says registered dietitian Katey Davidson, M.S., R.D. “Both fiber and protein take longer to digest, which will help keep you full longer. Fiber also helps to absorb excess cholesterol, which supports heart health,” she adds.

However, Davidson says it’s equally important to watch out for sugar alcohols. True: They’re technically acceptable on the keto diet because they don’t count toward total net carbs (and they give products a sweet taste without actually using sugar), but they can also lead to cramping and digestive issues for a lot of individuals. (Especially considering the keto diet often leads to constipation too.)

A good rule of thumb: Keep the ingredient list as simple as possible. Davidson recommends focusing on plant-based fats (which are higher in monounsaturated and polyunsaturated fats). These are better for heart health.

Overwhelmed already? No worries. Here, Davidson and other nutritional pros recommend the best keto protein bars according to these guidelines.