Pea Protein vs Whey: Which One Is Right for You?
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Whey protein powder has been used as a muscle building supplement since the 1950s, but the last decade has exposed a need for a plant-based protein alternative that can rival the benefits of its animal-based counterpart. Unlike other plant derived protein sources, pea protein is one of the few complete plant-based proteins (in addition to soy). This means that it contains all nine of the essential amino acids our bodies need to build muscle and can’t produce by themselves.
Whether you follow a plant-based diet, avoid dairy or simply want to consume more plant proteins, you’ve likely considered trying pea protein. But how does it stack up to the OG—whey? And is it as effective at promoting muscle gain and weight loss? In this comparison, we analyze what the science has to say about these two protein sources, the key differences and similarities and the important factors to consider when choosing between them.
What Is Pea Protein?
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Pea protein is a type of protein derived from yellow split peas that are ground into a fine flour and then processed to remove excess starch and fiber. This technique transforms the pea flour into a high-quality protein. Unlike many other plant-based protein sources, pea protein is considered complete, meaning it contains all nine of the essential amino acids our bodies need. This makes pea protein a great option for vegan and vegetarian consumers who are looking to supplement their diets with additional plant-based protein. Being dairy-free, pea protein is also a great choice for individuals with certain dietary restrictions. The main complaint about this plant-based protein powder is its traditionally grainy texture, though recent pea protein powders are much smoother.
What Is Whey Protein?
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Whey protein is a type of protein extracted from milk in which the whey is separated from other components, such as casein and fat, through a filtration process during cheese manufacturing. Being animal-based, whey is a complete protein, meaning it contains all nine essential amino acids the body can’t produce by itself. Whey protein powder is commonly used as a dietary supplement, particularly by athletes and bodybuilders, to increase muscle mass and support muscle repair and recovery. The primary downside to whey is lactose sugars that may cause digestion discomfort for those sensitive to dairy; however, those with lactose intolerance should experience significantly fewer symptoms by choosing a whey isolate instead of a whey concentrate.
What’s the Difference Between Whey and Pea Protein?
| Type | Source | Processing | Gluten? | Lactose? | Flavor | |
|---|---|---|---|---|---|---|
Pea Protein | Plant-based | Peas | Mechanical | No | No | Unflavored & flavored options available |
Whey Protein | Animal-based | Milk | Chemical | No | Sometimes | Unflavored & flavored options available |
Similarities
Both whey and pea protein are considered complete protein sources since they have all nine essential amino acids. This is important because the body requires all 20 essential and non-essential amino acids to function optimally and build muscle, and the nine essential amino acids must be consumed through your diet. Another similarity is that they are very common protein powders, so you shouldn’t have trouble finding these products in stores or online marketplaces. Most supplement companies offer both whey and pea protein to accommodate consumers. Up until a few years ago, there was a distinct taste difference between whey and plant-based protein powder, but that’s no longer the case—many rank their flavor profiles and taste as equally smooth and delicious, though there are always exceptions.
Related Post: The Best Tasting Protein Powders to Help You Achieve Your Fitness Goals
Finally and most importantly, both protein powders can stimulate equivalent levels of muscle protein synthesis (the process of building muscle) in the body. It was long believed that animal proteins were far superior to their plant-based peers; however, a recent study found that the overall rate of muscle protein synthesis between the two groups was similar. This research indicates that, as long as you ingest enough protein to induce muscle protein synthesis, it doesn’t matter whether the amino acids come from animal or plant protein sources. Although you may need to consume slightly more pea protein than whey protein, they ultimately produce the same muscle-building results.
Differences
The most apparent difference between pea and whey protein is that whey is an animal-based product, while pea protein is plant-based. And as an animal product, whey protein powders contain lactose, a sugar found in mammal milk. Lactose intolerant individuals may respond better to pea protein or a more processed whey, such as a whey protein isolate or hydrolysate.
The most impactful difference between the two protein powders concerning muscle building is their amino acid profile. Whey protein powder is slightly higher in leucine, a branched-chain amino acid that is primarily responsible for muscle growth and repair. For that reason, individuals looking to achieve optimal muscle growth should consume a slightly higher amount of pea protein, or supplement with additional leucine, to achieve a similar muscle protein synthesis response compared with whey protein.
Protein Content
Whey and pea protein contain essentially equivalent amounts of dietary protein, but they have different individual amino acid profiles. Whey protein is slightly higher in the BCAA leucine than pea protein. This is why we recommend that individuals looking to maximize muscle growth consume a slightly higher dose of pea protein than whey or supplement with additional leucine to attain the same rate of muscle protein synthesis.
| Essential Amino Acids | Complete Protein (min %) | Pea protein (%) | Whey protein (%) |
|---|---|---|---|
Histidine | 1.8 | 2.5 | 1.7 |
Isoleucine | 2.5 | 4.8 | 6.4 |
Leucine | 5.5 | 8.5 | 10.6 |
Lysine | 5.1 | 7.5 | 9.6 |
Methionine | 2.5 | 1.9 | 4.4 |
Phenylalanine | 4.7 | 5.5 | 5.6 |
Threonine | 2.7 | 3.7 | 6.7 |
Tryptophan | 0.7 | 1 | 1.4 |
Valine | 3.2 | 5 | 5.9 |
Data sourced from researchgate.net
Allergens
Pea protein is considered hypoallergenic, which means it’s free from common allergens and unlikely to cause an allergic reaction. On the other hand, whey protein is made from milk, and dairy allergies are quite common. If you’re sensitive to cow’s milk, then it’s best to avoid milk products such as whey protein. However, if you’re lactose intolerant (not allergic to dairy), you may be able to tolerate a whey protein isolate since almost all of the lactose is removed during the filtration process.
Forms
Protein supplements come in various forms, including powders, shakes, smoothies, bars and baked goods. You can find both whey and pea protein versions of each product. If you’re looking to add extra protein to your diet, there's no one-size-fits-all approach. Just know that protein powders are the highest protein-to-calorie supplement on this list. The shakes, smoothies, bars and baked goods will likely have extra calories from additional sources of carbohydrates and fats.
Nutrition
| Pea Protein (one ounce) | Whey Protein Concentrate (one ounce) | Whey Protein Isolate (one ounce) | |
|---|---|---|---|
Calories | 102 | 108 | 110 |
Protein (grams) | 20 | 19 | 25 |
Fat (grams) | 2 | 1 | 1 |
Carbohydrates (grams) | 1 | 5 | 1 |
Sugar (grams) | 0 | 1 | 0 |
Fiber (grams) | 0 | 0 | 0 |
Cholesterol (milligrams) | 0 | 57 | 10 |
Calcium (milligrams) | 36 | 72 | 121 |
Sodium (milligrams) | 272 | 106 | 45 |
Iron (milligrams) | 7 | 0 | 0 |
Potassium (milligrams) | 71 | 158 | 155 |
Data sourced from FoodData Central (usda.gov)
Pea protein and whey protein have very similar calorie and macronutrient profiles. They have almost identical amounts of protein and differ slightly in the number of carbohydrates and minerals. With such similar nutrient profiles, pea protein and whey protein concentrate are effectively interchangeable in an individual's diet. Whey protein isolate is filtered, so it has a higher concentration of protein and calcium, but fewer carbs and fat.
Comparing the Effectiveness of Whey and Pea Protein
Effectiveness for Muscle Gain
The science is clear that both whey and pea protein will promote similar strength, performance and muscle gain when used in combination with a resistance training program. There appears to be a slight difference in the amount of whey or pea protein necessary to build new muscle tissue due to the difference in leucine content, a key amino acid for stimulating muscle growth. On average, pea protein has a leucine content of 8.5 percent, while whey protein is 10.6 percent. In a 30-gram serving size of both whey and pea protein, whey has 3.2 grams of leucine, and pea protein has 2.6 grams.
To stimulate maximum muscle protein growth, you need to consume 3 to 4 grams of leucine per serving of protein. This means a 30-gram serving of whey protein contains leucine within the 3 to 4-gram range, but the same amount of pea protein does not. You need to up the dose of pea protein from 30 grams to 36 grams to fall within that range or supplement with additional leucine. Remember that for most of the population, the difference between consuming whey and pea protein is essentially irrelevant. This is really only important for high-level athletes and bodybuilders who are looking to completely optimize their performance, recovery and lean muscle growth.
Effectiveness for Weight Loss
If you’re currently pursuing a weight loss goal, then a protein powder can be an effective tool to aid you on your journey. Protein powders are lean sources of dietary protein that are mostly free from the extra calories that come from the carbohydrates and fats found in other dietary proteins like meat, legumes, eggs and dairy. This helps individuals maintain an adequate intake of protein while limiting their total caloric consumption. This is important because being in a caloric deficit is necessary for weight loss.
Another added benefit of dietary protein is that it’s the most satiating macronutrient, which means that it will keep you full for a longer period of time. This satiating effect is helpful for anyone in a caloric deficit that experiences high levels of hunger and can ultimately lead to consuming fewer calories throughout the day.
Related Post: The Best Protein Powders to Keep You Fueled During Your Weight Loss Journey
Our Picks for the Best Pea Protein Supplements
Transparent Labs Organic Vegan Protein
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Transparent Labs Organic Vegan Protein is a combination of organic pea and rice protein, which ensures a complete and well-balanced amino acid profile. With only 130 calories per serving and 24 grams of protein, this is a lean plant-based protein. It comes in two flavors—French Vanilla and Chocolate—and is 10% off when you subscribe for monthly delivery.
Legion Athletics Plant+
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Legion Athletics Plant+ is a rice and pea protein powder blend containing 25 grams of protein per serving—on the higher end compared to other brands. Brown rice protein concentrate has 18 amino acids, including eight essential ones, and when combined with the pea protein, provides a complete protein source. Plant+ comes in six flavors—Salted Caramel, Cinnamon Cereal, Apple Pie, Dutch Chocolate, French Vanilla and Mocha Cappuccino—and Legion avoids the use of artificial ingredients, utilizing only natural sweeteners and flavors. Subscribers save 10% on monthly deliveries.
KOS Organic Vegan Protein
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KOS Organic Vegan Protein features an organic blend of plant-based protein sources, including peas, flax seeds, chia seeds, pumpkin seeds and quinoa. This supplement has a typical macronutrient profile for a plant-based protein and has 160 calories, 20 grams of protein, 9 grams of carbs and 6 grams of fat. KOS is known for having some of the best-tasting plant-based protein on the market, with notable flavors including Blueberry Muffin, Chocolate Chip Mint, Chocolate Peanut Butter and Salted Caramel Coffee. Subscribers save 20% on monthly deliveries.
Gainful
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Gainful is a supplement brand that personalizes its products to suit your fitness and dietary needs. This means they offer consumers both whey and plant-based protein powder options. The brand's plant-based protein is usually a blend of organic yellow pea, organic brown rice and organic oats, and the exact macronutrients vary depending on the exact formula they personalize for you. Gainful offers individual flavor packets to enhance your shake. Flavors include Caffé Mocha, Chocolate Peanut Butter, Cinnamon Toast, Cookies & Cream, Matcha Green Tea, Madagascar Vanilla, Strawberry Cream and Sea Salt Caramel. This is a more expensive option, but it includes a personalized formula and access to a registered dietitian.
Our Picks for the Best Whey Protein Supplements
Transparent Labs 100% Grass-Fed Whey Protein Isolate
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Transparent Labs 100% Grass-Fed Whey Protein Isolate is one of the leanest proteins on the market with 28 grams of protein and only 120 calories per serving. Transparent Labs offers supplements free from artificial sweeteners, flavors and colors, and they have a wide variety of flavors ranging from Cinnamon French Toast and Chocolate Peanut Butter to French Vanilla and Oatmeal Chocolate Chip Cookie. While not the lowest-cost protein on this list, you pay for ingredient quality and label transparency.
XWerks Grow
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XWerks Grow Whey Protein Isolate is also made using 100 percent grass-fed whey. Each serving contains 25-27 grams of protein, depending on the flavor you choose. The four flavors include Chocolate, Vanilla, Peanut Butter and Strawberry, and XWerks is known for having one of the best-tasting whey protein powders on the market. Consumers love that this product mixes easily in a shaker bottle, rarely clumps and has just the right amount of sweetness. Subscribers save 5%.
Legion Athletics Whey+
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Legion Athletics Whey+ rivals both Transparent Labs and XWerks as another lean protein supplement at 100 calories and 22 grams of protein per serving with no sugar, artificial sweeteners flavors or food dyes. Whey+ is offered in 17 flavors: Dutch Chocolate, Apple Pie, Banana Bread, Chocolate Peanut Butter, Salted Caramel, Cinnamon Cereal, Birthday Cake, Chocolate Hazelnut, Cocoa Cereal, Cookies & Cream, French Vanilla, Fruity Cereal, Honey Cereal, Mocha Cappuccino, Strawberry Banana, Mint Chocolate and Pumpkin Pie, and the brand offers an unflavored option. This protein is made with whey from grass-fed cows from small dairy farms in Ireland, and it’s non-GMO, gluten-free and soy-free. Subscribers save 20%.
Gainful
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As we noted in our picks for the best pea proteins on the market, Gainful is a personalized supplement company that offers both a whey protein concentrate and a whey protein isolate formula. The cost of this subscription-based service is relatively high, but it includes individual sessions with a registered dietitian, which are a great resource. The flavor packets allow you to choose from a variety of different flavors on a daily basis, and Gainful avoids artificial sweeteners, flavors and colors in its products.
Whey Protein vs Pea Protein FAQs
Does pea protein affect hormones?
Since pea protein is derived from plants and not animal products, it’s very unlikely that it will affect any hormones in the body outside of the ones that regulate hunger levels such as leptin and ghrelin. There is no evidence to suggest that pea protein affects sex hormones such as testosterone and estrogen. Pea protein is generally considered a safe and healthy source of dietary protein.
Does whey protein increase estrogen?
There is no scientific evidence showing that whey protein increases estrogen levels in the body. If you’re concerned about potential hormone disruptions, I suggest finding a protein powder made with whey from cows that were never treated with steroid hormones (XWerks Grow is a good example).
What protein is the least inflammatory?
Being hypoallergenic, pea protein is considered less inflammatory than whey protein. That being said, whey protein is considered safe for the majority of people. In fact, one study that measured C-reactive protein (CRP), a common marker of inflammation in the body, in response to whey protein intake found that supplementation reduced circulating CRP levels in the blood. The only issue is for individuals with lactose intolerance or milk allergy; in these cases, whey protein can cause mild inflammation.
Are pea and whey protein heavily processed?
Pea protein is considered a processed food since it goes through a manufacturing process to extract the protein from the peas; however, the processing is considered minimal since it’s mechanical, not chemical. Whey protein is considered heavily processed because it goes through multiple stages of alteration from its original form. It’s important to note that just because something is processed doesn’t necessarily mean it’s bad for you or unhealthy. What matters more is the amount and type of processing. Aim for unprocessed or lightly processed foods and foods that are processed without chemicals or excessive heat.
What is the healthiest form of protein?
Both whey and pea protein are considered healthy if you need to add some extra protein to your diet. If you don't have any sensitivities or allergies to these products, then they’re both excellent sources of additional dietary protein. One isn’t healthier than the other unless you have a specific intolerance or allergy.
Are whey and pea protein hard to digest?
Whey protein is digested well by most individuals and absorbed rapidly in the body at around 10 grams per hour. This makes it an excellent choice for rapid muscle repair and recovery post-workout. Depending on the pea protein manufacturer and total fiber content of the supplement, it may take slightly longer for pea protein to digest than whey. However, one study shows that, despite the slight difference in digestion time, the absorption of amino acids between the two protein powders is similar (around 90 percent).
Final Thoughts
Both whey and pea protein powder supplements are phenomenal sources of additional dietary protein. For most people, the only major reason for consuming one type over the other is dietary restrictions or preferences. Outside of elite bodybuilders and athletes, there is a negligible difference between the health, weight loss and muscle gain benefits offered by the two products, so my suggestion is to find a protein powder that digests well, tastes great and fits within your budget.
Prices are accurate and items in stock as of publish time.
