The Best 6 Soy Protein Powders of 2023

Are Soy Protein Powders Beneficial?

Soy protein powder can be beneficial for those with high protein needs, such as highly active individuals or competitive athletes. It can serve as an easy means of refueling to promote muscle growth and recovery after a workout. Particularly for plant-based eaters with higher protein needs, soy protein powder can be a great resource. Populations who may benefit from soy protein powder include:

• Athletes. Endurance athletes’ protein needs can be nearly double those of an average sedentary adult, and strength-based athletes’ protein needs can be even higher. Therefore, as an athlete, you may benefit from supplementary forms of protein. Particularly if you are a vegan athlete, soy protein powder can be a beneficial addition to your refueling regimen since it is a complete protein. If you are not a competitive athlete but you are a highly active individual, you likely still fall into this category.
• People following a plant-based diet. A common concern for people eating plant-based is inadequate protein consumption. While there are plenty of plant-based protein food options, if you do not enjoy these or find it difficult to get enough at certain times of day (such as breakfast), then you may not be meeting your protein needs. Soy protein powder can be an easy means of boosting your protein intake. 
• People on-the-go. When we’re on the go, it can be hard to always get a complete meal. Soy protein powder can be a helpful resource if you need an easy, portable meal or snack. For example, you can have a well-balanced smoothie for breakfast using soy protein powder as one ingredient.

Who May Not Benefit From Soy Protein Powder?

• People with an iodine deficiency. Some research shows that soy may have a negative effect on thyroid function in those with an iodine deficiency. Therefore, if you are iodine deficient, you may want to consider a different vegan protein powder option.
• People who are pregnant. Pregnant individuals have higher protein needs, but there is little research on the effect of soy isoflavones on fetal health, so you may want to avoid soy protein powder until more research is available. 
• People who are sedentary or minimally active. If you are generally healthy, minimally active, and eat a diet that includes a good source of protein at each meal, then your protein needs are likely achievable through food alone. 
• People with kidney problems. Because overconsumption of protein can be taxing on the kidneys, you may want to be careful with protein powder intake if you have a kidney problem. Protein powder has high amounts of protein in a small volume, so it can be easier to exceed protein needs.

How We Selected

Our team works hard to be transparent about why we recommend certain supplements; you can read more about our dietary supplement methodology here.

We support supplements that are evidence-based and rooted in science. We value certain product attributes that we find to be associated with the highest quality products.

It's important to note that the FDA does not review dietary supplements for safety and effectiveness before they go to market. Our team of experts has created a detailed, science-backed methodology to choose the supplements we recommend.

To help come up with this list, we consulted with sports dietitian Starla Garcia, M.Ed, RDN, LD.

What to Look For

Third-Party Testing

Supplements that are third-party tested are sent to a lab where they are tested to ensure they contain what they say they contain and are not contaminated with specific high-risk, common contaminants. However, it’s important to note:

1. Third-party testing does not test to see if a product is effective or safe for everyone, and it does not ensure the supplement will not interact with other supplements or medications.
2. Not all third-party testing is created equal. It is not uncommon for supplement companies to pay labs for certificates after conducting minimal to no testing. 
3. The third-party certifications we can trust are: ConsumerLab, NSF, and USP. However, these certifications are difficult to obtain and/or expensive for manufacturers, so many companies choose not to get their products tested by one of these three organizations. 
4. Sometimes products tested by these three companies are more expensive to try to offset the cost they pay for certification.
5. Just because a supplement is not tested by one of these three companies, it does not mean it’s a bad product. We recommend doing some research on the reputability of the manufacturer and calling up the manufacturer and their testing lab to determine their protocols and decide if you feel comfortable consuming the supplement.

Protein powders may contain trace amounts of heavy metals, especially those that are plant-based. This is likely related to plants’ uptake of heavy metals through the air, water, and soil. However, the levels found in protein powders have not been found to be harmful when consumed in moderation. Purchasing third-party tested products helps ensure the product does not contain harmful levels of heavy metals.

Form

While soy protein can be found in concentrated and hydrolyzed forms, soy protein isolate is the form used for soy protein powders. This means the protein itself has been extracted from the soybean, removing the carbohydrates and fat.

Ingredients & Potential Interactions

It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included relative to the recommended daily value of that ingredient. Please bring the supplement label to a healthcare provider to review the different ingredients contained in the supplement and any potential interactions between these ingredients and other supplements and medications you are taking.

Protein powders can contain added sweeteners, food allergens, or performance enhancers. Reading the ingredient list and purchasing third-party tested products whenever possible can help you avoid consuming a product that aggravates intolerances or contains ingredients you are allergic to.

Soy Protein Powder Dosage

Always speak with a healthcare professional before adding a supplement to your routine to ensure that the supplement is appropriate for your individual needs and to understand which dosage to take.

The Dietary Guidelines for Americans recommend that sedentary adults consume 0.8 grams of protein per kilogram of body weight each day. For a 150-pound individual, this means 55 grams of protein, and for a 200-pound individual, this means 73 grams of protein.

However, this can vary greatly based on your physical activity level, whether you are pregnant or lactating, or if you have other medical conditions that affect protein needs. For a competitive athlete, protein needs can reach 1.4 to 2 grams per kilogram of body weight, which is why protein powders can particularly benefit this population.

It is generally best to get your nutrition from a variety of sources. While soy protein powder can contribute to meeting your protein needs, you may want to regularly incorporate a variety of protein sources to ensure you get enough methionine and reap the nutritional benefits of other food sources of protein.

How Much Is Too Much?

While there is no tolerable upper limit (UL) for protein, research has shown that consuming over 2 grams per kilogram long-term can result in renal, vascular, and digestive abnormalities. Researchers have proposed an upper limit of 3.5 grams per kilogram of body weight.

There are other risks of consuming too much soy protein, which include:

• Inadequate consumption of vitamin B12
• Inadequate methionine consumption
• Overconsumption of heavy metals
• Inadequate consumption of carbohydrates and fats