Secret Shopper: How do I choose a good protein powder? Are more grams of protein per serving always better? Are there other nutrient add-ins I should look for?
Store: How will you be using it? Are you trying to build muscle?
Secret Shopper: Not necessarily. I’m really ramping up my workouts and eating less meat so I want to make sure I’m getting enough protein. I’d like a powder to add to my morning smoothies.
Store: That’s a great way to go. If you’re using it mainly to supplement your diet, then any of these whey proteins will be sufficient. An isolate will be mainly protein, very little fat and carbs. But you can also go plant-based. Many of these contain vitamins, minerals, omega-3s and even probiotics.
Secret Shopper: And I can get enough actual protein from the plant-based options?
Store: Definitely. Your body can really only handle like 23 grams over a set period of time, so any extra is just waste.
How did this retailer do?
Our expert educator: Heather Mangieri, RDN, CEO of Nutrition CheckUp in Pittsburgh and author of Fueling Young Athletes (Human Kinetics, 2016).
This retailer got it right with his recommendations and seems very knowledgeable about the topic. However, while his comment about 23 grams is correct, his explanation was not 100 percent accurate.
Consuming between 20 and 30 grams of protein at one time is the amount found to maximize muscle protein synthesis. So it’s not that your body can’t handle any more—it’s that consuming more than that in one serving provides no additional muscle-building benefit. You’re better off keeping it to 20 to 30 grams and consuming that three to four times over the course of a day.
The retailer was also correct about both whey and plant-based powders being good sources of protein. All varieties have strengths and weaknesses. For example, whey protein dissolves in water better and offers a higher concentration of branched-chain amino acids. Plant-based varieties likely include a greater carbohydrate content in addition to protein. Consumers should base their choices on individual athletic goals and taste preferences.