Protein powder pros and cons: What to know, what to watch out for

Story highlights

  • Convenience is the top benefit protein powders offer, especially for athletes
  • Too much protein -- starting at about 35% of daily calories -- can lead to health issues

(CNN)Protein powders are expected to be a $7.5 billion industry by 2020, and the products are popular for a wide variety of reasons: Vegetarians might feel that their diets are somewhat lacking, athletes may want to add muscle faster or aim for a competitive edge, and still others might be looking for a quick meal that isn't dripping with grease.

And there's an equally wi