How to Stop Feeling Sick After Protein Shake

📌 Overview and Key Takeaways

This is a Certified Nutrition Coach’s guide on how to stop feeling sick after drinking a protein shake.

Discover how to reduce symptoms like bloating, diarrhea, and stomach pain.

Last Updated
May 22, 2026

Author and Medical Reviewer

Written by Jack, CNC

Jack is a National Academy of Sports Medicine Certified Nutrition Coach.

Disclaimer: This article is for general informational purposes only and is not a substitute for personalized medical advice. Consult a licensed healthcare professional before making changes to your diet.

Feeling Sick After Drinking a Protein Shake

If you just drank a protein shake and feel sick to your stomach, you have come to the right place.

This article will help you understand why your protein supplement upset your stomach and how to manage your symptoms.

How Do I Relieve Stomach Pain from a Protein Shake?

The first thing you should do if your protein shake makes you feel sick is stop drinking it.

It is likely that one or more of the ingredients is upsetting your stomach.

The next course of action is to address your symptoms.

Most symptoms will go away after a few hours, but there are a few things you can do to make yourself more comfortable.

How to Resolve Nausea:

• Drink lots of water. The body needs water to efficiently digest and absorb nutrients from foods and beverages. Dehydration makes digestion difficult, which increases the likelihood of an upset stomach.
• Sit or stand. People with an upset stomach should avoid lying down or going to bed.
• Eat ginger. Ginger might help reduce nausea.

How to Reduce Bloating and Gas:

• Exercise. Physical exercise, like going on a walk, can help you pass gas and reduce bloating.
• Drink peppermint tea. This easy home remedy also has a long history of reducing bloating and gas.

How to Deal With Diarrhea:

• Drink water, broth, or sports drinks. Staying well hydrated and getting lots of electrolytes is important if you have diarrhea.
• Eat plain foods. There is no particular food or food group that can reduce diarrhea, but bananas, white rice, applesauce, and toast are all safe things to eat.

How to Get Rid of Constipation:

• Drink warm water. Drinking lots of water, especially warm or hot water, can help you poop.
• Exercise. Movement can stimulate the muscles in your digestive system.
• Eat more fiber. Fiber increases the size of your stool, which helps it move through your digestive tract. It also softens your stool, making it easier to pass.
• Drink coffee. Caffeine can stimulate the muscles in your digestive system.

Depending on the nature and severity of your symptoms, these tips and tricks might help you feel better.

Please keep in mind that every stomach is different, however, so what works for one person might not work for someone else.

It is also important to note that most gastrointestinal symptoms just need time to subside.

If the do not go away after a few days, however, then please consult a healthcare professional.

Why Do Protein Shakes Make Me Feel Sick?

Many protein shakes contain ingredients that can cause painful side effects and even long-term digestive health problems.

Among these ingredients are food additives, dairy-based proteins, and protein concentrates and isolates.

🚫 Avoid Food Additives

Ultra-processed food additives like emulsifiers, thickeners, and artificial sweeteners tend to be hard to break down and absorb.

As a result, they can cause digestive issues like bloating, diarrhea, and stomach pain.

Regularly eating certain additives can also alter the composition and function of your gut microbiome – the collection of microorganisms living in your digestive tract (North Clin Istanb, 2020).

These shifts, known as gut dysbiosis, have been linked to a number of chronic digestive issues (JGH Open, 2021).

Gut dysbiosis is so problematic because it causes a cascade of problems, including intestinal permeability, systemic inflammation, and impaired nutrient absorption.

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

• acacia fiber
• acacia gum
• acesulfame potassium
• artificial flavors
• ascorbic acid
• aspartame
• calcium carbonate
• carrageenan
• cellulose gum
• dextrin
• dicalcium phosphate
• dipotassium phosphate
• erythritol
• gellan gum
• guar gum
• gum arabic
• inulin
• locust bean gum
• maltitol
• maltodextrin
• mono- and diglycerides
• ‘natural’ flavors
• rice bran extract
• rice dextrin
• rice hulls
• rosemary extract
• silica
• silicon dioxide
• sodium alginate
• soluble corn fiber
• sorbitol
• soy lecithin
• sucralose
• sunflower lecithin
• tocopherols
• tricalcium phosphate
• xanthan gum
• xylitol
• zinc oxide

As a rule of thumb, if you cannot find it in nature or make it at home, it is probably a food additive.

🚫 Avoid Dairy-Based Proteins

Dairy-based proteins like whey and casein, although not a problem for everyone, can cause digestive issues too.

This is usually because they contain lactose – a sugar many individuals with sensitive stomachs cannot fully digest.

But you might be sensitive to dairy-based proteins even if you are not lactose intolerant.

For starters, the digestion of some caseins releases a bioactive peptide that has been linked to digestive issues (Adv Nutr, 2017).

Casein also forms a gel-like substance in your stomach that slows down digestion (Crit Rev Food Sci Nutr, 2023).

For sensitive individuals, particularly true for those with cow’s milk protein allergy or intolerance, slower digestion can contribute to bloating, constipation, and other side effects.

🚫 Avoid Protein Concentrates and Isolates

If you have a sensitive stomach, you might also want to avoid protein concentrates and isolates.

Most protein supplements are made from one or both of these ultra-processed protein sources, which have been mechanically and/or chemically stripped of everything but the protein.

This includes the enzymes, fiber, and other natural digestive aids that help you break them down.

You therefore do not digest them in the same way that you do whole foods, which could affect your gut health.

For example, one study shows that regularly consuming protein concentrates and isolates might disrupt your gut microbiome (Nutrients, 2018).

Another study shows that it could cause the formation of toxic byproducts in your gut (Mol Nutr Food Res, 2024).

Although further research is needed, individuals with sensitive stomachs can play it safe by choosing protein supplements made from minimally-processed protein sources like egg whites and almonds.

They are more gut-friendly.

Order Samples to see for yourself.

Sources

1. Northern Clinics of Istanbul (North Clin Istanb). Food additives and microbiota. 2020.
2. JGH Open (JGH Open). Gut microbiota dysbiosis in functional gastrointestinal disorders: Underpinning the symptoms and pathophysiology. 2021.
3. Advances in Nutrition | Journal (Adv Nutr). Systematic Review of the Gastrointestinal Effects of A1 Compared with A2 β-Casein. 2017.
4. Critical Reviews in Food Science and Nutrition (Crit Rev Food Sci Nutr). Milk proteins: Processing, gastric coagulation, amino acid availability and muscle protein synthesis. 2023.
5. Nutrients (Nutrients). Effect of a Protein Supplement on the Gut Microbiota of Endurance Athletes: A Randomized, Controlled, Double-Blind Pilot Study. 2018.
6. Molecular Nutrition & Food Research (Mol Nutr Food Res). In Vitro Fermentation of Animal and Plant Protein Isolates by the Human Gut Microbiota Under High and Low Carbohydrate Conditions. 2024.

Editorial Guidelines

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This article was written by a Certified Nutrition Coach’s and reviewed by a Registered Dietitian. We rely on peer-reviewed research and trusted medical sources, and regularly update our content to ensure accuracy and clarity.