Soy Protein vs Whey

Soy protein is similar to other plant-based proteins (pea, brown rice, hemp, etc.) in that it is completely vegan, and a suitable alternative to whey for those who don’t consume any dairy. 

Soy protein is made through an extraction process which removes most of the fat and fiber from soybeans in order to create a high-protein powder. 

Similar to whey, soy protein comes in the form of concentrates and isolates. Soy protein concentrates will typically have a protein concentration of around 70%, while isolates have a protein concentration closer to 90%. 

Unlike many other plant-based proteins, soy contains high amounts of all 9 essential amino acids, making it a complete protein. This makes soy a dietary staple for vegans, as there aren’t too many plant-based foods that are considered complete proteins. This also makes soy a common ingredient in many plant-based protein blends alongside incomplete proteins like pea and brown rice. 

While getting adequate protein through a vegan diet is less of a concern than many people think, it can still be difficult for vegans to get high amounts of protein in, especially if they’re trying to build muscle. Because of this, plant-based protein supplements like soy can be a convenient way to reliably get some extra protein in. 

Whey protein is by far the most commonly consumed protein supplement on the market. Alongside casein, whey is a dairy product commonly processed and sold as a protein powder. 

Whey and casein are the 2 types of protein found in dairy. Whey is typically separated from dairy when making cheese, where it is clarified, pasteurized, and dried to form whey protein powder. It is then processed further to produce whey concentrates and isolates. Concentrates will typically have a protein concentration of around 80%, while isolates will be 90% or higher. 

Similar to soy, whey is also a complete protein, meaning it contains all 9 essential amino acids. With most animal-based proteins being complete, getting enough of each amino acid is a much smaller concern for omnivores than it is for vegans and vegetarians. 

For those who naturally get enough protein through their diet, especially if they already eat meat, eggs, and dairy, protein supplementation is largely unnecessary. With that being said, if you’re trying to build muscle, protein supplementation is a convenient way to hit your daily target, especially if there is a need for high doses of protein (e.g. athletes on a hypocaloric diet).

Soy protein and whey have very similar macros, especially when comparing high-quality isolate supplements. As you can see from the table above, while both protein supplements have high protein contents, whey slightly edges out soy in this category. It’s also worth noting that whey protein is more bioavailable than soy, making it a superior choice for most people. 

While soy protein is one of the better tasting plant-based proteins, it still has a somewhat chalky texture especially when compared with whey. Most people will much prefer the smooth texture of whey to soy protein. 

As you can also see from our product comparison, soy protein is significantly cheaper than whey. Comparing two high quality isolates, the soy product is nearly half the price of the whey. So, if you’re looking for a good budget option, soy may be a better choice for you over whey. 

Finally, soy is completely vegan-friendly while whey is not. Whey will be the go-to for most non-vegans, but for those who don’t consume any dairy products, soy protein is one of the highest-quality alternatives around.

So, is whey protein better than soy protein? Not necessarily.

Overall, when considering whey vs soy protein, these are very similar supplements that serve slightly different purposes. 

While their macros are similar, whey will typically have slightly more protein content, as well as being more bioavailable than soy. In terms of flavor and texture, whey will also have a much creamier, smoother texture than soy. For price, soy is significantly cheaper than whey, making it a good budget alternative. And finally, whey isn’t vegan-friendly while soy is, making soy the far superior option for those who don’t consume dairy. 

All in all, while most people will prefer whey for its bioavailability, excellent macros and flavor, if you’re vegan or looking for a budget-friendly alternative, soy is a great choice as well.

Both soy and whey protein serve the same purpose: a convenient source of protein to help people hit their daily macro goals. As such, the difference between whey and soy protein when it comes to use is very minimal. If you’re struggling to get enough protein throughout the day, mixing either of these products into a shake or a smoothie can be an easy and reliable way to hit your protein goals. 

If you’re looking for a high-quality whey supplement, we recommend trying Transparent Labs Whey Isolate. 

As this is an isolate supplement, you can expect a stellar 93% protein concentration by calories. With 120 calories, 28g of protein per serving, 0g of fat, and only 1g of carbs, this is a perfect supplement for bulking. 

Transparent Labs whey is also derived from organic grass-fed dairy, which has been shown to be healthier than non-organic milk. On top of this, like all of Transparent Labs’ products, you can expect no artificial ingredients whatsoever.

One slight downside here is that this product doesn’t have much flavor variety. It only comes in the 2 most standard protein powder flavors: chocolate and vanilla. Also, as previously mentioned this is a fairly expensive product at around $1.82 per serving. Keep in mind, this is also for the 4lb tub as it offers the best value for money. With this being said, you’ll be hard-pressed trying to find a higher-quality whey supplement at any price point. 

Next, if you’re looking for a great soy protein, then check out MyProtein’s Soy Protein Isolate. 

While soy typically has the highest protein content of all plant-based protein supplements, there aren’t many other soy proteins available with macros as impressive as this product. It rivals a whey isolate with a solid 95% protein concentration by calories. With 110 calories, 26g of protein, 0g of fat, and 1g of carbs, this is also an ideal supplement for dieting. 

It’s worth noting that MyProtein doesn’t have the same all-natural formula as Transparent Labs, featuring several artificial ingredients such as sucralose. 

MyProtein also offers a slightly more impressive flavor profile than Transparent Labs with 5 options to choose from. They offer 2 variations each on chocolate and vanilla, as well as an unflavored option. 

As mentioned above, this is a much more budget-friendly option when compared to whey isolate, coming in at around $0.81 per serving – that’s over a dollar cheaper than Transparent Labs! So, if you’re looking for budget-friendly or vegan protein powder, this would be a great choice.  

Overall, if you’re trying to decide between soy or whey protein powder, both have their advantages. If you’re vegan, or looking for a budget-friendly alternative, then soy protein will be perfect for you. However, if you’re looking to maximize bioavailability and protein content, as well as have a tastier shake, then whey will be for you. Whichever protein type you decide, both are high-quality, convenient sources of protein. 

If you’re looking for a high-quality whey isolate supplement, we recommend going with Transparent Labs Whey Isolate. If you want a great soy protein instead, then check out MyProtein Soy Protein Isolate.

Have you tried both whey and soy protein? Which one do you prefer? We’d love to hear your thoughts in the comments below!

References:

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3. Marjorie Geiser, The wonders of whey protein, http://surl.li/kxjrv.
4. Brad Heins, "Grass-fed cows produce healthier milk" University of Minnesota Extension, http://surl.li/kvogd (accessed 2021).
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