Do your protein powder blends contain soy? Eric Wu February 12, 2019 15:53 Updated All of Gainful's products are 100% soy-free! Related articles What is the difference between whey protein isolate and concentrate? Are Your Flavor Boosts Keto Friendly How do I gain weight? What are your vegetable protein sources? Do your shakes include fruit and vegetable nutrients? Comments 0 comments Please sign in to leave a comment.