Plant-Based Protein Supplements

By Dwayne N. Jackson, PhD

Protein powders are the hottest selling supplements in the industry, and for good reason—science has unequivocally proven that daily protein supplementation builds muscle, increases strength, and supports fat loss. For decades we have heard about the pros and cons of soy, egg, whey, and casein protein supplements and it is well established that milk proteins (whey and casein) corner the market in bodybuilding.

Currently, whey protein isolate (WPI) is the anabolic gold standard, while micellar casein is the benchmark for anti-catabolic nighttime protein supplements. So, what is it that makes these milk proteins work so well for building muscle? Well, science suggests that their main effects are due milk’s high concentrations of essential amino acids, including the highest level of branched chain amino acids (BCAAs). Beyond that, high quality WPI naturally contains BCAAs in a 2:1:1 (leucine:valine:isoleucine) ratio, which has been proven ideal for muscle building. Finally, pure WPI is virtually carb and fat free and is chock-full of arginine, glutamine, and alanine, which further support growth and fat loss.

Supplement research and development teams are continually pushing the envelope to produce new products for us, but like most new developments they must avoid “reinventing the wheel” or “fixing something that isn’t broken”. Yet with the advent of new isolation and filtering technologies several alternative source protein supplements have recently hit the market. Some are touted to be better than whey, while others are available as alternatives to animal proteins. In the following article we review the latest plant protein sources using WPI as our benchmark for muscle building quality, taste and price.

Pea Protein Isolate

Pea protein isolate is becoming popular among vegan bodybuilders, those who prefer proteins from non-GMO sources (most pea protein supplements are non-GMO), and/or those who have intolerance to milk proteins. Good quality pea protein isolate contains high levels of the BCAAs (comparable to WPI) in 2:1:1 (leucine:valine:isoleucine). Furthermore, like WPI, pea protein isolate is highly digestible (90-95%) and extremely high in glutamine and arginine. Good products tend to be 80-85% protein and contain modest amounts of fat (about 2 g) and about 1 g of fiber in a 30 g scoop.

Cost? We have found high quality pea protein isolate at nearly half the price of comparable quality WPI.

Taste? Most say it is tolerable, but its texture and taste are poor compared to WPI.

Availability? A few companies sell pea protein isolate powder, it is easily obtainable online.

Benefits/Drawbacks? High digestibility and comparable amino acid profile to WPI make this an ideal supplement for vegetarians or those with milk allergies. Pea protein isolate’s low price-point make it very desirable to those who need a great protein source but have a tight budget. We predict that this product will gain popularity as whey prices continue to rise.

Potato Protein Isolate

Potato protein isolate is fat and carbohydrate free and contains high levels of essential amino acids (2 x the amount of arginine than WPI), and a robust concentration of BCAAs. Compared to WPI, it contains about half the glutamine and alanine, similar levels of leucine and isoleucine and twice as much valine. Like WPI, high quality products are over 90% protein making this an attractive option (at face value). Unfortunately, there are limited data on the digestibility of potato protein isolate, but the general consensus is that it causes major gas and flatulence.

Cost? Very expensive, about 50% more money than comparable quality WPI.

Taste? Many complain that it tastes intolerably sour.

Availability? A few companies sell potato protein isolate powder, it is easily obtainable online.

Benefits/Drawbacks? Amino acid profile and protein concentrations are comparable to WPI, which makes this an option for vegans or those with milk allergies. Potato protein isolate’s high price and the fact that it may lead to gas/flatulence make it less desirable than other vegan protein sources.

Rice Protein Concentrate

This stuff is made from whole grain brown rice and has an amino acid profile that rivals WPI; to illustrate, rice protein contains a similar concentration of BCAAs, has comparable glutamine and alanine levels, but over 4x the arginine. Currently isolated forms of rice protein are rare, so as a protein concentrate it has a lower protein per serving (80%) than WPI (90-95%). This isn’t really an issue though, as rice protein concentrate is virtually fat free and the only carbs it contains are in the form of fiber (a whopping 2.4 g per scoop!).

Cost? We have found rice protein concentrate at nearly half the price of WPI.

Taste? Poor tasting

Availability? Highly available

Benefits/Drawbacks? It has an amino acid profile comparable to WPI, which makes this an option for vegans or those with milk allergies. Its low price-point make rice protein concentrate very desirable to those who need a great protein source but have a tight budget. We predict that this product will gain popularity as whey prices continue to rise. Finally, its high fiber content slows digestion and may help to regulate blood glucose.

Hemp Protein Concentrate

No, this protein source was not developed for bodybuilding hippies, but rather a vegan alternative to animal based protein products. Like milk, hemp has two constituent proteins, edestin and albumin, where edestin makes up about 65% (hence, albumin makes up the other 35%). Research suggests many nutritional benefits to hemp protein ingestion, as it contains relatively high amounts of essential omega-3 and 6 fatty acids (about 3 g) and fiber (about 5 g per scoop). However, it only contains about 50% protein per scoop and has a lackluster amino acid profile.

Cost?

Higher priced than other much better vegan alternatives (about the same price as WPI).

Taste?

pparently it has a very nutty taste, but tolerable

Availability?

Highly available

Benefits/Drawbacks?

High fiber and essential fatty acid content make hemp protein something you may want to add to your meal replacement shake. Unfortunately, its low protein yield, mediocre amino acid profile, and relatively high cost limit hemp protein concentrate as a standalone protein source.

Based on our report, you can see that there are still no clear-cut replacements for WPI supplements. However, if you are vegan, allergic to milk products, or just looking to save some money there seems to be some worthwhile options.