Why do protein shakes make me feel sick?

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

Most protein shakes make me feel sick, which is why I created drink wholesome. It 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. This makes it perfect for people with gut issues and sensitive stomachs, as well as for people just looking to boost their protein intake without the processing and added junk. Order samples to see if my protein powder is right for you. 

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

-Brittany Carpenter, MS, RDN/LDN


vanilla protein powder

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3 protein powder samples


Protein shakes can make you feel sick.

Can protein shakes make you feel sick?

Why do protein shakes make me feel sick?

Why drink wholesome?

Can protein shakes make you feel sick?

Protein shakes are notorious for making people feel sick or nauseous (as if they are going to vomit). Nausea can last anywhere from a few minutes to a few hours, and understanding why it occurs can be tricky. Sometimes, it is simply a question of eating too much or eating too fast, but it can also be related to the type of food you ate, and how it affects your digestion. 

Believe it or not, most protein supplements are not easy to digest. There are several reasons why this is so, and we will get into those shortly. All you really need to know is that foods that are hard to digest cause a number of unpleasant side effects, one of which is nausea. 

making a protein shake with protein powder

Why do protein shakes make me feel sick?

There are two types of protein shakes: ready-to-drink (store-bought) protein shakes, and homemade protein shakes made with protein powder. Both are known to make people feel sick, and for the same reasons. Virtually all ready-to-drink protein shakes and most protein powders contain ingredients that are hard to digest.

The ingredients that tend to be the hardest to digest are food additives like emulsifiers, stabilizers, thickeners, sweeteners, and flavors. Ingredients like these look nothing like real food, and your gut does not know what to do with them. Additives therefore sit in your digestive tract for longer than food should, which leads to one of two outcomes: either water is drawn into your intestines, resulting in diarrhea, or the additives feed your gut bacteria, which produce gas. The accumulation of gas can cause feelings of nausea, as well as bloating, flatulence, stomach pain, and even constipation.

But wait, there is more. Over time, eating food additives can disrupt regulatory pathways within the intestines, contributing to the development of inflammatory bowel disease (IBD) and other systemic inflammatory disorders. Food additives, particularly artificial sweeteners, also possess the potential to disturb the delicate balance of the gut microbiome — the collection of microorganisms that help you digest food. As you can imagine, this can significantly impact your gut health and impair your ability to digest food.

woman drinking a protein shake

Why drink wholesome

drink wholesome is additive-free.

One of the reasons why our protein powder will not make you feel sick is that we do not use food additives. As you just learned, food additives are bad news for digestion, and one of the leading reasons why protein shakes can make you feel sick. 

vegan vanilla protein powder serving suggestion
vanilla protein powder lifestyle image 1

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

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.

drink wholesome is dairy-free.

Another reason why our protein powder will not make you feel sick is that we do not use dairy-based protein like whey and casein. Whey and casein, which are byproducts of  the production of cheese and yogurt, are notorious for making people feel sick. This is especially true for individuals with lactose intolerance, as they lack the enzymes needed to fully break down lactose, the sugar in dairy. As you now know, the presence of undigested food can result in a number of undesirable side effects, including nausea.

drink wholesome is made with real foods.

A final reason why our protein powder will not make you feel sick is that we do not use protein isolates. The majority of protein powders, in contrast, rely on either one or both of these protein sources, which are basically foods stripped of everything but the protein. Instead of being labeled as “peas” or “whey,” concentrates and isolates appear as “pea protein” or “whey protein” on the ingredient list.

Creating protein concentrates and isolates involves rigorous mechanical and chemical processing. In some instances, chemical solvents like hexane are utilized to extract the protein from its natural source. Consequently, your protein powder bears no resemblance to real food.

Your digestive system has evolved to handle minimally or unprocessed real foods, not artificial copy cats. Consuming anything other than real food can, therefore, lead to adverse side effects. While the long-term effects of consuming processed food products such as protein isolates are still under investigation, emerging studies suggest that they can significantly disturb the balance of the gut microbiota, causing lasting damage to the digestive system.

In addition to its vital role in food digestion, the gut serves as a protective barrier against harmful pathogens, plays a crucial part in educating the immune system, and affects various physiological processes. As a consequence, disruptions to the delicate equilibrium of the gut microbiome have been closely associated with the development of chronic illnesses. Considering this connection, I strongly advise against consuming protein powders made with protein concentrates and isolates.

vegan chocolate protein powder lifestyle image 1
chocolate protein powder serving suggestion

Instead of protein concentrates or isolates, we make protein powder with egg whites and almonds. Egg whites are simply pasteurized and dried, and almonds are just roasted, pressed to remove some oil, and ground. These minimally-processed ingredients yield a protein powder that is easily digestible and beneficial for gut health, and a healthy alternative to protein concentrates and isolates.

For individuals who do not have allergies or sensitivities to eggs, egg white protein emerges as an exceptional choice for enhancing gut health. With a low fiber content and minimal FODMAPs, egg whites are gentle on the digestive system. Moreover, they possess the highest protein digestibility-corrected amino acid score (PDCAAS) among all whole foods. Our happy customers consistently provide positive feedback, noting fewer digestive issues when consuming our egg white protein powder than when consuming other protein sources.

For those unable to consume eggs, our vegan almond protein powder serves as a superb replacement. Almonds, unlike protein concentrates or isolates, are abundant in healthy fats, fiber, and essential nutrients like calcium and vitamin E. We prioritize almonds over other minimally-processed plant protein sources due to their remarkable gut-friendly properties. Research indicates that almonds exhibit prebiotic characteristics, fostering the diversity and composition of the gut microbiome, ultimately supporting better gut health.

To summarize, our protein powders undergo minimal processing to prioritize the well-being of your gut.


easy to digest

“I have tried every other protein powder and it all makes me throw up sick! I tried yours tonight and my stomach doesn’t hurt and I’m not sick!!” – Mallory

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drink wholesome will not make you feel sick. 


vegan chocolate protein powder

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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.