Soy Protein Isolate

Questionable Keto Ingredient

What is Soy Protein Isolate?

Soybeans can also be used to make soy protein powder. To make soy protein isolate, defatted soybean flakes are washed in water or alcohol to take out the dietary fiber and sugars. The flakes are then dehydrated and turned into a powder. The end result contains little fat and no cholesterol. Soy protein powder is often used in infant soy formula and numerous dairy and meat alternatives. One ounce (28 grams) of soy protein isolate powder provides 95 calories, 2 grams of carbs, 1.6 grams of fiber, and 23 grams of protein. It also gives you copper, manganese, phosphorus, and other nutrients.

Keto Status?



High Protein and low carb. Concerns are raised about the phytoestrogen content of soy, which might disrupt natural hormone levels in the body. Phytoestrogens are naturally occurring plant chemical compounds with estrogen-like properties. These phytoestrogens bind to estrogen receptors in the body, and soy is a considerable source of phytoestrogens.

For more information on possible risks associated with phytoestrogens, follow this link:

Possible Side Effects From Ingesting Soy Protein Isolate?

Hypothyroidism, endocrine problems, digestive issues

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PLEASE NOTE – I Heart Keto Mart will add more sources and up-to-date research articles as they come to our attention. We welcome any of our viewers to send us any information/research/articles that you think would be of interest to our rating decision. Keep in mind – we are not rating ingredients solely on their general health benefits or side effects. To see our rating process, click on the link below.

I Heart Keto Mart Rating Guide

I Heart Keto Mart rates all ingredients through a “keto diet” & “low carb diet” lens. As an example, peas would be rated as “Acceptable” on a non-keto healthy diet; however, due to their carbohydrate level, we rate them “Objectionable”. We also rate all sweeteners that typically cause a rise in blood sugar and insulin levels as “Objectionable”. If you prefer a natural sweetener, like honey, over a sugar alcohol like erythritol, you may not agree with our “Objectionable” rating. I Heart Keto Mart rates all ingredients based first and foremost for those that have a sugar/carbohydrate addiction. Ingredients are rated for those who must moderate if not completely abstain from any sugars. If you have questions about this, please refer to this article: Why Some Whole Foods Are Not Keto Friendly


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