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Hello! I’m Anjali. I’m a board certified health coach, author, wife, mom and food lover from the SF Bay area (now living in Seattle, WA!); with a passion for delicious food and a desire to make healthy eating easy, tasty and fun! Learn more about me here and stay for a while!

Anjali Shah

The Truth About Fake Meat & Protein Bars (or: Should You Eat Soy Protein?)

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A few weeks ago, I was chatting with the husband about protein bars.

Since he (and I) are vegetarian and since we are both super active, I’m always looking for healthy, veggie-friendly protein. Unfortunately, with all of the fake-meat-soy-products and soy-based protein bars out there – that’s often hard to come by.

This is because soy protein isolate has been used as a high protein source in many veggie-friendly products – which I tend to avoid eating (more on that later).

I was explaining all of this to the husband, and he pointed out that the information out there on soy in general is super confusing, as is knowing what types of nutrition bars or veggie-friendly protein products are healthy to eat.

And he’s right! I was confused about soy protein for the longest time (half the articles out there tout it as a superfood, and half of them vehemently disagree with eating soy), and it was only after I did lots of reading and research that I was able to come to a few conclusions of my own.

So here it is …

The Picky Eater’s Guide to Soy: What to Eat and What Not to Eat!

First, let’s look at unprocessed soy products like tofu, tempeh, miso, etc. as well as non-soy protein that people sometimes confuse as soy (seitan).


What are these products? 

  • Edamame are whole “young” soy beans – they are picked before the bean has hardened so you can eat them right from the pod.
  • Tofu is made from whole soy beans. It is the bean curd that is mashed into blocks (after coagulating soy milk).
  • Tempeh is made from fermented whole soy beans. The fermentation process binds the soy beans into a cake form.
  • Miso is a thick paste made from fermented soybeans and barley or rice malt. It is used in Japanese cooking to make soups or sauces.
  • Soy Milk is produced by soaking dry soy beans and grinding them up with water.
  • Seitan isn’t soy at all! It’s actually a wheat protein made from wheat gluten.

Should you eat them? (you’ll see a theme here 🙂 )

  • Edamame: Eat only if it’s 100% organic and non-GMO
  • Tofu: Eat only if it’s 100% organic and non-GMO
  • Tempeh: Eat only if it’s 100% organic and non-GMO
  • Miso: Eat only if it’s 100% organic and non-GMO
  • Soy Milk: Eat only if it’s 100% organic, non-GMO, and if the only two ingredients on the label are Whole Organic Soy Beans and Water
  • Seitan: If it’s organic, 100% natural (no chemicals or other ingredients you can’t pronounce), and if you can tolerate gluten – it is fine to eat.

Why is it important to only eat organic soy?

Because over 90% of the soy in this country is genetically modified (GMO), unless it is organic. That means it’s more chemically altered, sprayed with toxic pesticides, and more processed compared to its organic relative.

The Bottom Line: Out of all of the unprocessed, whole soy products above – I’d recommend sticking to the fermented versions like tempeh and miso and enjoying the other soy products in moderation (more on why in the question below). And always choose 100% organic, non-GMO for any soy products you buy!


Now – onto the second question: What’s with the whole estrogenic-properties-of-soy thing? 

Soy contains phytochemicals called isoflavones (aka phytoestrogens). Phytoestrogens are natural plant hormones that mimic estrogen in our bodies. For some people, these estrogens may help balance their hormones, but they can also throw off the hormonal balance for other people. The jury is still out on whether phytoestrogens are beneficial or “superfood-like.”

Eating soy is NOT the same as taking estrogen by any means. But some people are more sensitive to phytoestrogens than others — which is why I try to only eat whole soy products in moderation (not more than once or twice a week max). And I probably wouldn’t use soy-based forumla for babies because who knows how those phytoestrogens affect little ones.

BUT fermented sources of soy (like miso, tempeh, and natto) are actually better than non-fermented sources. Fermentation increases the digestibility of soy, adds good bacteria, and reduces the plant estrogen content in soy foods.

Side note: People with low thyroid functioning need to limit their soy consumption since soy contains substances called goitrogens which can slow the production and/or release of thyroid hormones in the body.

The Bottom Line: Eat soy in moderation and choose fermented when possible!


Lastly – the big question: What’s the deal with soy protein isolate and all of the veggie-friendly protein bars/products?

If you take a look at the nutrition label of most protein bars, veggie burgers, or fake-meat products, you’ll see soy protein isolate featured as one of the main ingredients.


So what is soy protein isolate? 

Soy protein isolate (SPI) is basically the isolated protein component from the soy bean. Creating SPI requires a heavily chemically engineered process to “isolate” that protein: the end result of which is a denatured protein that is stripped of all the nutrients (fiber, minerals, complex carbs) that the original bean contained.

Additionally, to isolate the soy protein, the soy beans are soaked and sprayed with chemicals like aluminum and hexane – which often leaves behind residue that you don’t want to be eating. Hexane is a neurotoxic petrochemical solvent that is listed as a hazardous air pollutant with the Environmental Protection Agency (EPA). The spray-drying method used for soy can also form nitrites – compounds that can form carcinogens in the body.

And if that’s not enough, SPI is always GMO and filled with pesticides.

Lastly, SPI has a higher concentration of trypsin inhibitors – which are chemicals that reduce trypsin (an enzyme that helps digest protein) in the body.

So SPI may have started out as a plant, but once it gets to you, it’s far from it. The products that use SPI also have the craziest list of ingredients and are super processed themselves (methylcellulose or disodium inosinate anyone?) – which is another reason to stay away from those products altogether. Remember if you can’t pronounce it, you probably don’t want to be eating it.

Some tips about SPI – it can be “hidden” under other names like:

  • textured vegetable protein (TVP)
  • soy protein concentrate
  • Soya, Soja or Yuba,
  • textured soy flour (TSF)
  • textured soy protein (TSP)

The Bottom Line: NEVER eat products containing soy protein isolate or any “terms” related to soy protein isolate in the list above. Read your ingredient lists carefully and stay away from products with long ingredient lists you can’t pronounce!

This can be hard because lots of popular brands: Clif Bars, LUNA Bars, MorningStar, etc. have SPI on their ingredients list. But there are many other products out there that don’t! You just have to be a little more diligent and read the labels (health food stores and Whole Foods definitely have other options). 


The Bottom Bottom Line: What to do if you’re vegetarian or want non-meat-protein sources?

#1 | Stick to natural, whole protein sources like beans, eggs, cottage cheese, Greek Yogurt, lentils, nuts, seeds and organic, non-GMO natural sources of soy like edamame, tempeh and tofu (free of sugar, artificial sweeteners, or other additives)

#2 | Try making veggie burgers at home or buy frozen veggie burgers that don’t have SPI like this kind from Amy’s

#3 | Stick to protein-bar brands that don’t use Soy Protein Isolate like Zing , LaraBar UBER, and CORE FoodsKIND is a good option as well, but read the labels carefully – some of their bars do have soy protein isolate in them! The KIND bars that don’t are a tasty and healthy snack.

#4 | If you like protein powder – try Amazing Meal or SunWarrior

That’s basically it!

In general shopping for healthy packaged food can be a challenge, but remember it’s all about reading the ingredients and knowing which ones to avoid. I hope this post helps you navigate the world of soy!

Check out these other helpful healthy eating guides!

95 responses to “The Truth About Fake Meat & Protein Bars (or: Should You Eat Soy Protein?)”

  1. Hi Anjali,
    Thank you for the detailed post! It cleared a lot of questions about protein choices for vegetarians. However I would like to know we if you have any authoritative articles to support the link between eating soy affecting people with hypothyroidism.

    • Hi Jaya! Thanks for reaching out! I’m glad you found this post helpful. To your question – it’s not necessarily that people with hypothyroidism have to avoid soy completely, but soy can have an effect the absorption of hypothyroid medication (indicated here), and I think this article describes how soy can affect the thyroid at a more general level. Hope that helps, let me know if you have any other questions!

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