Pea Protein VS Soy Protein: Which is Better for You??

pea protein vs soy protein

By now, you probably already know the importance of getting adequate protein in your diet. Protein is needed by every cell in your body. It also helps build and repair muscle, skin, and other tissues within the body.

In my opinion, protein is one of the most important macronutrients there is. It is especially beneficial to preserve lean muscle mass during weight loss while you lose fat.

I always recommend meeting your protein needs through a well-balanced diet, but it isn’t always easy. Especially if your protein needs are high or you are a vegan. One way to ensure your protein needs are met is by taking a high-quality protein powder supplement.

Lately, pea protein has been gaining attention as a good source of plant-based protein. However, we still see many impressive soy protein supplements pop up, too!

In this article, I will take an in-depth look at pea protein vs soy protein, two popular plant-based protein powders on the market. I will discuss pea protein vs soy protein and their nutritional composition. By the end of the article, I hope you will better understand each to choose one that fits your lifestyle best.

What is Pea Protein?

Pea protein is made from extracting protein from peas, often yellow split peas. The protein is extracted through a manual food production process where dried peas are ground into a very fine powder.

Once that’s done, the majority of the starch and fiber are removed to create pea protein concentrate. Pea protein powder has a unique smooth, creamy texture. In my opinion, I consider it to have an earthy, natural taste.

Unlike other protein powders like whey, it is lactose-free since it is not derived from dairy.

While pea protein contains all nine essential amino acids to be considered a complete protein, it is relatively low in methionine, an essential amino acid.

Depending on the brand of pea protein you choose, some powders may not meet the ratio of essential amino acids necessary to be considered a complete protein. 

Many companies may add methionine or other plant-based proteins like rice or hemp protein high in methionine to provide a more complete amino acid profile.

Pea protein powder is also a great source of BCAAs (leucine, isoleucine, and valine) that promote muscle growth, reduce muscle soreness, and support healthy blood flow.

Lastly, some older studies suggest it may absorb fewer heavy metals than soybean. However, we really need more research because any plant-based protein from the ground will absorb some amount of heavy metals and be higher than non-plant-based protein sources like whey protein. This is because heavy metals are naturally present in water and soil.

pea protein image

Nutritional Composition of Pea Protein Per 30 gram, 1-ounce Serving

Here’s a look at the average nutritional composition of a 1 ounce (30 gram) scoop of pea protein powder:

  • Calories: 120
  • Protein: 22.5 grams
  • Fat: 2.25 grams
  • Carbs: 1.5 grams
  • Fiber: 1.5 grams
  • 7% Daily Value (DV)
  • Sodium: 345 milligrams, 15% DV
  • Iron: 42% of the DV

What is Soy Protein?

Soy protein isolate (SPI) is made from… you guessed it! Soybeans. Soy protein powder is made through a process known as “acid-washing.” Basically, this involves soaking soybeans in either acid or alcohol to remove the dietary fiber and sugar. From there, it’s further processed until you are left with a fine powder that is around 95% protein. It’s also nearly carb and fat-free!

Soy protein is often used in protein bars, meat alternatives, and other packaged foods to amp up the protein.

Unlike many other plant-based proteins, soy protein is a complete protein. This means that it contains all nine essential amino acids that your body cannot make. Soy protein is also a good source of branched-chain amino acids (BCAA’s).

Is Soy Protein Bad for You?

Recently, there has been a lot of controversy about the use of soy protein. Most of this can be attributed to the chemical processes used to isolate the protein in soy. It can lead to substances and chemicals left behind in the powder.

Studies show that protein powders like soy may have high levels of heavy metals in them. However, at this time, researchers believe the amount found in protein powders is not sufficient to lead to cancer or any adverse health effects.

Even if it’s likely not enough to be toxic or harmful, it’s important to try to limit toxins and chemicals as much as possible from our diet to avoid overexposure. 

Many people shun soy because of the fear that soy can lead to adverse health outcomes.

For example, one study from 2016 found women who had a higher soy intake had an increased risk of having elevated levels of thyroid-stimulating hormone (TSH). Elevated TSH may indicate an underactive thyroid.

However, researchers concluded that soy is more than likely safe, but excess consumption may pose health risks for some people, such as those with undiagnosed hypothyroidism.

With that said, there have also been studies that show soy protein meal replacements and shakes may support weight loss. However, we really need more solid studies.

Another study found that a higher intake of foods containing soy can lead to decreased risk of breast cancer. However, there is very little evidence to suggest taking soy isoflavone supplements decreases the risk and incidence of breast cancer.

According to the National Center for Complementary and Integrative Health, soy is generally safe for most people without soy allergies. Studies surrounding the short-term use of soy protein supplements and extracts show safety. However, the safety of long-term use lacks sufficient evidence.

Based on the weak evidence surrounding the negative effects of the short-term use of soy, most soy protein powders are considered safe in moderation for the general population.

image of soy protein

Nutritional Composition of Soy Isolate Protein Per 28 gram, 1-ounce Serving

Here’s a look at the average nutritional composition of a 1 ounce (30 gram) scoop of pea protein powder:

  • Calories: 96
  • Protein: 23 grams
  • Fat: 1 gram
  • Carbs: 2.1 grams
  • Fiber: 1.5 grams
  • Calcium:5% Daily Value (DV)
  • Sodium: 285 milligrams, 11% DV
  • Iron: 22% of the DV

While these numbers are pretty impressive, it’s important to remember the whole form of soybeans contains additional nutrients such as fiber and iron.

Read more: Weight Loss For Busy Moms

Pea Protein Vs Soy Protein: Similarities and differences

Pea protein:

  • Offers a nearly complete amino acid profile
  • Easy to digest 
  • High in protein
  • High in iron and fiber
  • Can effectively build muscle
  • Can help you meet your protein needs
  • Free of common allergens
  • High in BCAAs

Soy protein:

  • High in protein
  • Is a common allergen
  • A complete protein
  • Can effectively build muscle
  • Can help you meet your protein needs
  • Easy to digest
  • High in BCAAs
  • Usually cheaper

How to Choose the Best Protein Powder

The main thing you’ll want to do when choosing a protein powder is check for third-party testing. This can ensure your powder contains a safe level of heavy metals, the ingredients listed on the label, and is free of pesticides. 

If you opt for pea protein powder, I always recommend looking for a brand that pairs another plant-based protein source as well. This helps make a more complete amino acid profile.

You’ll also want to choose a protein powder free of added sugar and sugar alcohols which may cause bloating and belly pain in some people. 

Most importantly, you’ll want to choose a flavor that appeals to your taste buds. Thankfully, there’s a wide range of flavors in protein powders. You can also blend them in smoothies or other beverages to add more flavor. 

pea protein vs soy protein image comparison

The Final Verdict: Which Is Better, Pea Protein vs Soy Protein?

Pea protein and soy protein powder are both good options for protein powder. Soy protein is a complete protein source, whereas pea protein is “nearly complete.” It’s also cheaper.

However, understandably, some people are hesitant to use it because of the controversy surrounding its use. Though we don’t have any strong research to support negative side effects, I certainly do not encourage its use in someone with doubts.

I personally am a fan of pea protein and regularly drink shakes made with it. The best plant-based protein powder is one that fits your lifestyle, taste preferences, and budget! 

As always, it’s best to get your protein through whole food sources as much as possible. Consult with your health care provider before starting any supplements, including these two protein powders!

Does pea protein cause acne?

No, contrary to popular belief, pea protein does not cause acne. Dairy-containing protein powders such as whey and casein may affect insulin-like growth factor 1 (IGF-1) hormone, which can cause breakouts in some people. 

Is pea protein safe while breastfeeding?

Most protein powders are safe for breastfeeding, including pea protein. To maximize safety, be sure to choose a protein powder from a reputable company that is free of caffeine, ginseng, and fat burners. Always speak with your doctor before taking any supplementation during pregnancy. Check out the best protein powder for breastfeeding!

Scroll to Top