As if the protein powder aisle wasn’t confusing enough—here comes pea protein.

Yes, those mushy little orbs your mom made you eat as a kid do contain protein (about 10 grams per cup, in fact)

But with all of the protein powder options—whey, casein, soy, rice, hemp—lining health foods shelves, why would you ever reach for peas?

What’s the Difference?

For starters, pea protein is free of dairy, explains Sharon Palmer, R.D.N., author of Plant-Powered for Life. That’s important to both vegans and people with lactose intolerance or sensitivity.

But for the rest of the population, pea protein can also help deliver the quality of protein you need to help your muscles recover after exercise.

Pea protein is a complete protein, which means it contains all nine of the essential amino acids—including branched-chain amino acids (BCAAs)—that you need to consume to effectively build muscle, Palmer says. That’s not true of many other plant-based options like rice.

How Does Pea Protein Compare to Whey?

Side-by-side, here’s how pea protein stacks up against whey, the gold standard of protein powders, as calculated by Marie Spano, R.D., C.S.C.S., a sports nutritionist for the Atlanta Hawks.*

25 Grams Pea Protein 25 Grams Whey
Calories 162.5 157.4
Carbs 8.8 8.7
Protein 25 25
Fat 2.6 2.1
BCAAs 5.9 7.8

But Does Pea Protein Work?

Looking at the numbers, you would assume pea protein may not be as effective at building muscle as whey. After all, pea protein contains nowhere near the amount of BCAAs as whey.

But pea protein does have one advantage not captured in the information above—and that’s the fact that it houses about three times more of the amino acid arginine than whey.

Arginine may not be a BCAA, but it’s essential to building muscle, and may explain why pea protein does such a good job at boosting men’s muscle gains.

In a 2015 Journal of the International Society of Sports Nutrition study of men ages 18 to 35, those who paired their lifting sessions with pea protein enjoyed the same increases in biceps size as did those who opted for whey protein.

So Which Kind Of Protein Powder Should You Buy?

If you’re trying to avoid both dairy and soy, there’s no real downside to giving pea protein a try.

You can compensate for pea protein’s “slightly dirt-like” flavour by adding in other ingredients like fruit, veggies, and nut butters to your protein shake, Matheny says. Bonus: Mixing multiple protein sources into your pea-based protein shake affords you an even better amino acid profile than sipping on peas alone.

Matheny recommends looking for brands that state that their peas are both grown and processed in the United States.

“That will increase the likelihood that the protein was grown in clean soil without heavy metal contamination,” he says. Some products also advertise on their label that they have undergone third party testing for heavy metal content.

To make sure that your pea protein does not contain any hormones or unnecessary additives, he also recommends opting for organic and unflavoured tubs.

“But is there any reason to buy it if you aren’t vegan or allergic to both dairy and soy? Not really,” Matheny says. Pea protein’s high arginine levels are more of a “redeeming quality” as opposed to a reason to buy pea protein rather than whey