What are the bad ingredients in protein powder?

Written by Jack Schrupp and reviewed by Ella McGonagle, M.S. Nutrition

What are the bad ingredients in protein powder? In this article, I will review the ingredients in an average protein powder to give you a better idea of what might be in your protein powder.

“If you have a sensitive gut, you need simple ingredients.”

-Brittany Carpenter, MS, RDN/LDN


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The bad ingredients in protein powder.

What are real foods?

What are food additives?

The review.

Why drink wholesome?

What are real foods?

Real foods are foods close to nature. Picture an almond or a banana. A real food consists of one ingredient and has undergone little to no processing. 

What are food additives?

Food additives are heavily-processed derivatives of real food added to protein powder to improve characteristics like shelf life and texture. They generally fall into one of the following categories: flavors, colors, preservatives, anti-caking and gelling agents, emulsifiers, stabilizers, or thickeners. Although not necessarily bad for you in small quantities, additives can add up quickly (especially if you drink a protein shake every day) and cause gastrointestinal (GI) side effects like bloating, constipation, diarrhea, gas, and stomach pain. This is because food additives are hard to digest, and sit in your gut for longer than food should, which gives your gut bacteria more time to eat. As they eat, these bacteria produce gas, which causes bloating and stomach pain. Gas also slows colonic transit (the amount of time it takes food to travel through the colon), and can lead to constipation. In the long term, food additives can disrupt regulatory pathways in the intestine, which can result in the development of inflammatory bowel disease (IBD) and systemic inflammatory disorders.

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vanilla protein powder lifestyle image 1

When buying protein powder for sensitive stomachs, one ingredient to avoid in particular is artificial sweeteners. Artificial sweeteners are among the most harmful food additives in the long term as they alter the composition of your gut microbiota (the collection of microorganisms that help you digest food). This can lead to serious, chronic GI problems, widespread inflammation, and permanent damage to the gut microbiome. Some sweeteners, especially sugar alcohols like xylitol, are also poorly absorbed by the gut (meaning they feed those hungry gut bacteria), and cause diarrhea because they draw water into your intestine. Now you finally have something to blame for those post-protein shake trips to the bathroom!

Here is a list of the most common food additives in protein powder:

acacia gum, acesulfame potassium, artificial flavors, aspartame, carrageenan, cellulose gum, dextrin, dextrose, erythritol, gellan gum, guar gum, gum arabic, inulin, locust bean gum, “natural” flavors, maltodextrin, rice syrup solids, soy lecithin, silica, sucralose, sunflower lecithin, xanthan gum, xylitol

When it comes to identifying food additives, go with your gut. 😉 As a rule of thumb, they are the ingredients that you cannot pronounce. 

BSN protein powder
BSN protein powder ingredients

The review.

I reviewed the ingredients in one of BSN SYNTHA-6’s most popular protein powders, which also happens to be one of the most popular protein powders on Amazon.com. I counted all the real foods and all the food additives, and gave the protein powder a Wholesome Score, which is calculated on a scale from 1 (not wholesome) to 5 (wholesome). The more real foods and the fewer food additives a protein powder has, the higher its Wholesome Score is. This is not a scientific determination, but rather an honest attempt at greater transparency. Too often we use protein powder without thinking twice about what we are putting into our bodies. Now without further ado, here are the ingredients in BSN SYNTHA-6 Whey Protein Powder.

Protein Matrix Comprised of (Whey Protein Concentrate, Whey Protein Isolate, Calcium Caseinate, Micellar Casein, Milk Protein Isolate, Egg Albumen, Glutamine Peptides), Polydextrose, Sunflower Creamer (Sunflower Oil, Corn Syrup Solids, Sodium Caseinate, Mono- and Diglycerides, Dipotassium Phosphate, Tricalcium Phosphate, Soy Lecithin, Tocopherols), Natural and Artificial Flavor, MCT Powder (Medium Chain Triglycerides, Nonfat Dry Milk, Disodium Phosphate, Silicon Dioxide), Lecithin, Cellulose Gum, Salt, Yellow 5, Sucralose, Acesulfame Potassium, Papain, Bromelain.

Real Food Count: 4

Egg Albumen, Cocoa, Nonfat Dry Milk, Salt

*Notice that I did not include Whey Protein Concentrate, Whey Protein Isolate, or Milk Protein Isolate in this list. Although these ingredients may seem like real foods, they are not. Protein concentrates and isolates are heavily-processed ingredients chemically or mechanically stripped of everything but the protein. We will not go into the details, but some manufacturers use chemical solvents like hexane to isolate (separate) the protein from the food. This means that what you end up putting into your body looks nothing like real food.

Additive Count: 21

Glutamine Peptides, Polydextrose, Sunflower Oil, Corn Syrup Solids, Sodium Caseinate, Mono- and Diglycerides, Dipotassium Phosphate, Tricalcium Phosphate, Soy Lecithin, Tocopherols, Natural and Artificial Flavor, Medium Chain Triglycerides, Disodium Phosphate, Silicon Dioxide, Lecithin, Cellulose Gum, Yellow 5, Sucralose, Acesulfame Potassium, Papain, Bromelain

Wholesome Score: 1 (terrible)

Of the 25 listed ingredients, 21 of them are food additives, making BSN SYNTHA-6 Whey Protein Powder about as far from real food as you can get. It is for this reason that I gave it a Wholesome Score of 1 (out of 5). According to my criteria, BSN SYNTHA-6 Whey Protein Powder is not something you want to put in your body.; although it has protein, it is also full of added junk.

So, what are the bad ingredients in protein powder? To put it simply, the bad ingredients are anything that is not real food.

Why drink wholesome

drink wholesome is additive-free, dairy-free, and made with real foods, not protein isolates – 99% of supplements fail to meet at least one of these criteria. 

the alternative:

Protein Matrix Comprised of (Whey Protein Concentrate,  Whey Protein Isolate, Calcium Caseinate, Micellar Casein, Milk Protein Isolate, Egg Albumen, Glutamine Peptides), Polydextrose, Sunflower Creamer (Sunflower Oil, Corn Syrup Solids,  Sodium Caseinate, Mono- and Diglycerides, Dipotassium Phosphate, Tricalcium Phosphate, Soy Lecithin, Tocopherols), Natural and Artificial Flavor, MCT Powder (Medium Chain Triglycerides, Nonfat Dry Milk, Disodium Phosphate, Silicon Dioxide), Lecithin, Cellulose Gum, Salt, Yellow 5, Sucralose, Acesulfame Potassium, Papain, Bromelain.

*This is the actual ingredient list of one of the best-selling protein powders in the United States.


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This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. drink wholesome is not intended to diagnose, treat, cure or prevent any disease.