The overall rating for soy protein is 2.1 out of 3 meaning there is some evidence that this supplement does some (not all) of what it claims. Using this supplement may lead to some improvements.

What is soy protein?

Few foods evoke greater emotion than soy. It elicits fears of decreased testosterone, less optimal strength, and feminization of masculine features. There’s plenty of misinformation about soy. The truth is there are plenty of health and performance benefits to consuming soy protein with plenty of research to back it up. Read More

Table of Contents

  1. Articles
  2. Simple Report
  3. Detailed Report
  4. Overall Effectiveness Rating
  5. Research Rating
  6. Claim Ratings
  7. Dosing
  8. The Bottom Line
  9. References


Soy Protein Simple Report

  • Supplement: Soy Protein
  • Supplement Category: proteins
  • Number of Products Containing Soy Protein: 0
  • Effectiveness Rating: 2.1 out of 3
  • Research Rating: 36 (above 80 indicates sufficient research)
  • Number of Studies: 10
  • Number of Claims: 10
  • Effective Dosage Range: 22.2 - 50 grams per day

Soy Protein Detailed Report

Overall Effectiveness Rating

The overall effectiveness rating for soy protein is 2.1 out of 3. This rating means the evidence is mixed on the supplement's ability to deliver positive results. While some of the research supports its use, other evidence does not. Using this supplement may lead to positive results. Note, this effectiveness rating is for soy protein as a whole; there are also individual ratings for the claims below.

Read more: What is the effectiveness rating?

Research Rating for Soy Protein

There are 10 studies in the database on soy protein; the research rating is 36. A score above 80 means the effectiveness rating for this supplement is reliable. A score under 80 means there is insufficient evidence to ensure a reliable effectiveness rating. Note, this research rating is for soy protein as a whole; there are also individual ratings for the claims below.

Read more: What is the research rating?

Claim Ratings

The overall ratings above are an average of the individual claim ratings below. Individual claims may have higher or lower ratings compared to the supplement's overall rating. For example, some supplements may have excellent backing for one claim, but be completely useless for another. Click on a claim below for more information.

Body Composition (weight, muscle, body fat) Claims Effectiveness Rating Research Rating
decrease body fat
increase muscle mass
increase weight loss

Protein Synthesis Claims Effectiveness Rating Research Rating
increase protein synthesis

Performance Claims Effectiveness Rating Research Rating
increase strength

Cardiovascular Health Claims Effectiveness Rating Research Rating
lower LDL (bad) cholesterol levels
increase HDL (good) cholesterol levels
lower total cholesterol levels

Recovery Claims Effectiveness Rating Research Rating
reduce muscle damage
reduce muscle soreness


The Supplement Database includes 5 studies on soy protein dosing. These studies indicate an effective dose ranges from 22.2 to 50 grams per day, the average dose being 37.4 grams per day. For a more detailed dosing analysis visit: Supplement Dosing for Soy Protein.

The Bottom Line

Overall, the evidence shows that soy protein is extremely beneficial. Soy protein has numerous health benefits including decreasing the risk of some cancers and heart disease. It can increase strength and muscle mass, decrease body fat, and improve the recovery process. Soy is just as capable as other, more popular, protein supplements. Read full article: Final Verdict: Is soy protein worth taking?


Title of Study
Consumption of fat-free fluid milk after resistance exercise promotes greater lean mass accretion than does consumption of soy or carbohydrate in young, novice, male weightlifters
Effect of soy and milk protein supplementation on serum lipid levels: a randomized controlled trial
Effect of whey and soy protein supplementation combined with resistance training in young adults
Effects of Whey, Soy or Leucine Supplementation with 12 Weeks of Resistance Training on Strength, Body Composition, and Skeletal Muscle and Adipose Tissue Histological Attributes in College-Aged Males
Four Weeks of Supplementation With Isolated Soy Protein Attenuates Exercise-Induced Muscle Damage and Enhances Muscle Recovery in Well Trained Athletes: A Randomized Trial
Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men
Muscle strength gains during resistance exercise training are attenuated with soy compared with dairy or usual protein intake in older adults: A randomized controlled trial
One-year soy protein supplementation does not improve lipid profile in postmenopausal women
Supplementation with soy-protein-rich foods does not enhance weight loss
Whey Protein Supplementation During Resistance Training Augments Lean Body Mass