Protein bars have become a go-to source of nutrition for anyone living a fast-paced life. They offer a convenient way to supplement the diet while on the move. But with so many brands and varieties available in the market, it’s getting harder to differentiate between the ones made with natural ingredients like fruit, nuts, and whole grains and the more processed ones that use less compelling sweeteners like high fructose corn syrup.

It’s not just the corn syrup that’s worrisome, however. Protein bars often contain artificial sweeteners such as sucralose, aspartame, or acesulfame potassium. Per ABC News, consuming these sweeteners can negatively affect your gut microbiome and blood sugar regulation. On the other end, you’ll find the low-sugar bars sweetened with sugar alcohols like maltitol or sorbitol, which, according to Healthline, can cause digestive issues, such as bloating, gas, and diarrhea.

If you read the labels carefully, protein bars can be a handy supplement for protein, vitamin, and mineral intake, but they can never replace a whole, nutritious meal, according to Healthline. Always look for labels that are easy to understand and recognize the ingredients listed. Anthony DiMarino, a dietician for Cleveland Clinic, told the New York Times that high-quality protein snack should contain no more than 200 calories, minimal fat, added sugar (ideally no more than 5 grams), and a minimum of 15 to 20 grams of protein per serving.