Plant Protein Powder: An Overview

Melissa Halas MA, RDN, CDE | SuperKids Nutrition

“Amino acid profiles largely differed among plant-based proteins with leucine contents ranging from 5.1% for hemp to 13.5% for corn protein, compared to 9.0% for milk, 7.0% for egg, and 7.6% for muscle protein.”1 This shows that plant-based proteins can hold their own against animal proteins! See more on plant protein’s amino acid breakdown on MelissasHealthyLiving.com. There are four sources of plant protein powder most often seen on the shelves. Here is a breakdown:

Pea

Pea protein has recently become much more popular in the supplement space. One study compared whey and pea protein supplements and found comparable increases in muscle thickness from participants in both groups, so pea protein serves as a good substitute for those who want an alternative to whey.2 It is important to note that the leucine content of the pea protein used was 6.4 grams. While this was less than the 8.6 grams in the whey protein, it was still well over the 2-3 grams threshold for muscle protein synthesis. Some people don’t like the taste of 100% pea, which isone reason you often see blends.

• 1 ounce of pea powder = 27 grams of protein and 2.7 grams of leucine3

Soy

Soy is a complete protein and has a digestibility score that rivals milk-based proteins, which is why it is often compared against whey. Though soy protein is a complete protein, it only has small amounts of methionine.4 The research is mixed on its effect on protein synthesis and athletic performance. Some studies show comparable or improved muscle protein synthesis when compared to the milk proteins whey and casein. In short-term studies, soy has also been seen to be as effective as casein – the protein that makes up about 80% of milk.5

Additionally, a recent meta-analysis looking at nine different long-term studies comparing soy and animal protein supplementation (whey, beef, milk, or dairy) with resistance exercise training found that both groups had significant gains in strength, and there were no differences between the soy and whey groups.5 Despite these results, some studies suggest soy protein is inferior. This may seem conflicting, however, if you’re making progress towards your body composition goals, then you’re likely meeting your protein needs.6,7 In general once you meet your determined protein needs, excess protein intake won’t provide any additional benefit. Bottom line: meet your protein needs, don’t exceed them, then monitor your workout, and evaluate your results.

• 1 ounce of soy protein isolate = 25 grams of protein and 1.9 grams of leucine8

Rice

Rice protein is a hypoallergenic option with sufficient amounts of the amino acid, leucine, comparable to whey protein isolate. Leucine is particularly important in promoting muscle protein synthesis.9 The main thing to keep an eye out for with rice protein powders is to make sure you are using asupplement from a reliable source because many rice-derived products are contaminated with arsenic.4

• 1 ounce of rice powder = 25 grams of protein and 2.1 grams of leucine10

Hemp

Hemp protein brings unique nutritional components to a protein shake with regards to its high antioxidant and fiber content. For general comparison,hemp protein has a lower percentage of BCAAs than whey and soy, but higher than rice and egg protein.5 For competitive collegiate or professional athletes, or those who are drug tested, it is typically encouraged not to consume hemp, since it is harvested from the hemp plant Cannabis sativa. Consuming hemp protein increases the risk of a positive drug test due to traces of THC, even if the product claims that it doesn’t contain THC.

• 1 ounce of hemp powder = 15 grams of protein and 0.8 grams of leucine8

What Else is in the Bottle?

Soy, rice, pea, and hemp are commonly used as the base of plant-based protein supplements. Sometimes they are sold individually, but more often they are sold as a proprietary blend where the exact ratio of the mixture is unspecified. This may be done to achieve a more balanced amino acid profile and taste; however, in some cases, it can hinder transparency for the consumer. On occasion, a label may separately indicate a list of the exact amounts of each amino acid, which can help an athlete make an informed decision based on their needs. But given the varied nature of blendedproducts, it makes it difficult to conduct research on its effectiveness and create mass recommendations for the public. If you are uncertain about the dosing, consult with your RDN.

Other ingredients such as sweeteners, fiber, caffeine, creatine, individual amino acids, vitamins, and minerals are also commonly added tosupplements. These additives are often hidden in fine print on the label or within trademarked blends, which do not legally require manufacturers to list exact amounts of each addition.11 Keep an eye out for these and always be your own detective when buying supplements!

Your Plant Protein Takeaways

Now that you’re more familiar with all that protein powder can do (or not do), you can decide how it may fit into your typical eating pattern. It is alsoimportant to remember that you’ll likely be mixing this protein powder with something else – boosting the nutrient profile (and taste!). While many people like to mix their protein powder into a smoothie, some like to just mix it with a liquid for easy on-the-go consumption. Anytime you mix yourpowder with something else, be aware of the nutrition composition of the liquid (i.e., water, milk, juice, etc.) and/or the foods you’re adding to make sure you’re staying on track with your overall needs!

From this closer look at plant and animal-based protein powders, you can see that they have many different characteristics and that some are better than others. They also can vary quite a bit in their flavor profile. Here are a few key takeaways:

• Keep the leucine amount in mind if you have certain body composition goals

• Understand that there is a benefit to some plant-protein mixes to achieve a desirable amino acid profile

• Both animal and plant-based protein powders can help you meet your needs
  

Head to MelissasHealthyLiving.com for brand recommendations and a breakdown of nutrition facts, special features, additives, and third- party certifications! Join the newsletter for updates for helpful product recommendations.

Melissa Halas, MA, RDN, CDE, is CEO of SuperKids Nutrition and creator of the Super Crew. She's a nationally recognized Registered Dietitian specializing in pediatrics, sports, and plant-based nutrition. Check out her books that promote plant-based eating for both children and adults, including The Plant-Based Boost, Nutrition Solutions for Athletes and Exercise Enthusiasts, The Plant-Based Boost Cookbook, 100+ Recipes for Athletes and Exercise Enthusiasts, The Super Crew’s Breakfast Cookbook for Kids, 50 Tasty Recipes + 100 Fun Nutrition Activities, and Healthy Eating for Families, The Ultimate Nutrition Guide for Kids, Parents, and Educators (in English and Spanish). Shop her books here.

Contact Melissa.

References:

1. GorissenSHM,CrombagJJR,SendenJMG,etal.Proteincontentandaminoacid composition of commercially available plant-based protein isolates. Amino Acids.2018;50(12):1685-1695. doi:10.1007/s00726-018-2640-5

2. Babault N, Païzis C, Deley G, et al. Pea proteins oral supplementation promotes muscle thickness gains during resistance training: a double-blind, randomized, Placebo-controlled clinical trial vs. Whey protein. J Int Soc Sports Nutr. 2015;12(1):3. doi:10.1186/s12970-014-0064-5

3. Pea Protein Powder 5lb - Vegan & Gluten Free - Naked Pea. Naked Nutrition website. https://nkdnutrition.com/products/pea-protein-powder. Accessed March 3, 2019.

4. ConsumerLabs.com. Product Review: Protein Powders, Shakes, and Drinks Review. ConsumerLabs.com website. https://www.consumerlab.com/reviews/Protein_Powders_Shakes_Drinks_Sports/NutritionDrinks/. Published 2018.

5. Messina M, Lynch H, Dickinson JM, Reed KE. No Difference Between the Ef- fects of Supplementing With Soy Protein Versus Animal Protein on Gains in Muscle Mass and Strength in Response to Resistance Exercise. Int J Sport Nutr Exerc Metab. 2018;28(6):674-685. doi:10.1123/ijsnem.2018-0071

6. Hashimoto R, Sakai A, Murayama M, et al. Effects of dietary soy protein on skeletal muscle volume and strength in humans with various physical activities. J Med Investig. 2015;62(3.4):177-183. doi:10.2152/jmi.62.177

7. Hartman JW, Tang JE, Wilkinson SB, et al. Consumption of fat-free fluid milk after resistance exercise promotes greater lean mass accretion than does consump-tion of soy or carbohydrate in young, novice, male weightlifters. Am J Clin Nutr. 2007;86(2):373-381. doi:10.1093/ajcn/86.2.373

8. United States Department of Agriculture Agricultural Research Service. USDA Food Composition Databases. USDA Food Composition Databases website. https:// ndb.nal.usda.gov/ndb/. Accessed March 1, 2019.

9. Joy JM, Lowery RP, Wilson JM, et al. The effects of 8 weeks of whey or rice protein supplementation on body composition and exercise performance. Nutr J.2013;12(1):86. doi:10.1186/1475-2891-12-86

10. Organic Brown Rice Protein Powder - Naked Rice - 5lb. Naked Nutrition website. https://nkdnutrition.com/products/organic-brown-rice-protein-powder. Accessed March 3, 2019.

11. Almendarez S. The End of Proprietary Blends and other Supplement Issues for Sports Dietitians. Natural Products Insider website. https://www.naturalproductsin- sider.com/sports-nutrition/end-proprietary-blends-and-other-supplement-issues- sports-dietitians. Published 2014. Accessed March 2, 2019.