What Happens If I Switch to a Plant-Based Protein Powder?

If you're ready to leave your trusty old whey supplement behind, here's what to look for.
A massively swole hand holding a protein shake
simon abranowicz

There are plenty of valid reasons to transition from a tried-and-true whey protein supplement to a plant-based option. Maybe you recently learned you’re lactose intolerant. (Whey is a liquid that separates from milk during the production of cheese.) Maybe you want to consume less dairy. Maybe you’re a newfound vegan who wants to reduce your carbon footprint because global temperatures are spiking, natural disasters are growing more frequent and powerful, and sea levels are rising at terrifying rates! Whatever the case, I am here to help answer the most pressing question involved in this protein-sipping switchover: Can you still enjoy the same gains with a plant-based protein powder that you would with a whey protein powder?

These days, plant-based proteins are readily available from all sorts of sources: soy, peas, nuts, hemp, brown rice, chia seeds, pumpkin seeds, and so on. There is still a limited body of research out there on the effects of plant-based protein supplements, but the science that is available—with a few important caveats—indicates only a small difference between whey and some of the better plant-based sources.

“Whey may be faster-acting and have some minor additional benefits,” says Kelly Pritchett, Ph.D., an associate professor in nutrition and exercise science at Central Washington University who previously helped GQ solve the mystery of the absolute best time to drink a protein shake. “But are you really going to see those benefits directly? I don’t know if you will.”

Whey owes its historical dominance of the protein powder world to its generous helpings of the essential amino acids you need to repair muscle and bulk up. But plant-based proteins contain essential amino acids, too—just not necessarily in the same quantities. A 2019 study compared the weightlifting feats of two groups of people—one group that stuck to whey protein, while the other tried pea protein—over an eight-week period. The study concluded that “whey and pea proteins promote similar strength, performance, body composition, and muscular adaptations.” Put differently: Your one-rep maxes are highly unlikely to suffer after moving from whey to pea protein.

Pritchett identified soy and pea protein powders as two of the trustier plant-based protein sources. (Soy-based supplements have been around for a while, and pea-based supplements are the most recent, most popular vegan addition to the market.) But it’s probably in your best interests to look for a hybrid powder that uses more than only soy or pea proteins. Fortunately, many powders mash together all sorts of veggies and grains, delivering the sort of well-rounded, high-quantity amino acid profile that all gym enthusiasts should be seeking out.

Before you go looking for a powder that features every crushed-up plant under the sun, though, Pritchett advises turning to the experts for guidance. “My biggest worry as a dietician is whether people are using products that are third-party tested,” she says. There are a lot of plant-based products out there, and the people selling them make all sorts of claims about their efficacy. Whey protein, for all of its tummy ache-inducing issues, has been thoroughly researched, and the biggest whey protein powder brands use ingredients tested by independent third parties, meaning they’ve proven their worth to consumers for years. We aren’t there yet with plant-based choices.

To filter out the market’s more dubious offerings, make sure any plant-based protein selection has ingredients examined in some capacity by someone who isn’t the product’s manufacturer. The USDA’s organic designation, and NSF’s “Certified for Sport” certification, for example, are good places to start. Once you find a winner that fits your particular dietary needs, don’t be afraid to leave whey behind. “Plant-based protein powders can get the job done,” Pritchett says. No chocolate milk required.

This post has been updated to reflect Pritchett's current affiliation.