How to Find a Protein Powder That’s Easy on the Stomach

📌 Overview and Key Takeaways

This is a Dietitian’s guide on how to find a protein powder that is easy on the stomach.

Discover how to supplement your protein intake without causing stomach issues.

Last Updated
Jan 8, 2026

Author and Medical Reviewer

Written by Jack, Founder

Jack is the Founder of Drink Wholesome.

Medically reviewed by Brittany, MS, RD and Jenn, PA-C

Kayla is a Registered Dietitian with a MS in Nutrition.

Jennifer is a Physician Assistant with a BA in Nutritional Sciences.

Protein Powder That’s Easy on the Stomach

Why Does Digestion Matter?

How easy your protein powder is to digest can make a huge difference in terms of both how it makes you feel and how it fuels your body.

First of all, protein powders that are easy to digest are less likely to cause digestive issues like bloating and stomach pain.

If you ask me, that is reason enough to consider digestion before adding a new protein powder to my diet.

Digestion is far more complex than just how protein powder makes you feel in the short-term, however.

Because protein powder is something you consume regularly, if not every day, it can have a huge impact on the health of your gut microbiome.

And this collection of microorganisms not only helps you break down and absorb what you eat, but it also plays in important role in most essential physiological processes, including immunity and metabolism (Biochem J, 2017).

Are Some Types of Protein Easier to Digest than Others?

Some types of dietary protein are easier to break down and absorb than others.

The best way to measure these differences is by using the Protein Digestibility Corrected Amino Acid Score (PDCAAS), which takes into account both the amino acid profile of the protein and how easy it is to break down and absorb that protein (Br J Nutr, 2012).

Protein sources like eggs and dairy have a PDCAAS of 1.0, which is the highest possible score.

Most other protein sources score considerably lower, but that does not mean that they are not as good for you.

For starters, the PDCAAS is biased towards a dietary protein’s amino acid profile.

As a reminder:

• Amino acids are the building blocks of protein.
• There are 20 amino acids in the human body, 9 of which are essential, meaning we must get them from food.
• A dietary protein with all 9 essential amino acids is considered a complete protein.

Because eggs and dairy are complete proteins, they have a much higher potential PDCAAS than incomplete proteins like nuts or legumes.

This does not mean that eggs or dairy have more nutritional value, however.

Someone who eats a variety of protein sources is going to get all the essential amino acids they need.

In fact, 99% of adults easily meet 100% of their essential amino acid needs by eating a balanced diet (J Nutr, 2023).

In other words, the idea that some types of proteins are better for you only applies to someone who is not eating a balanced diet.

Plus, digestibility can be scientifically measured, it is also highly subjective.

For instance, people with lactose intolerance have a hard time digesting dairy, despite its high PDCAAS, because it contains lactose, a sugar that they cannot fully break down.

In short, although some types of protein are easier to digest than others, worrying about these differences is not good use of your time.

Instead, what you should be concerned about is how much processing and how many additives were used to make your protein powder.

Which Protein Powders Are Easy on the Stomach?

Although the type of protein powder you use does not matter, not all protein powders are created equal when it comes to digestion.

Many contain ingredients known to cause painful stomach issues and even long-term gut health problems.

Here are some of the top offenders:

🚫 Avoid Food Additives

Emulsifiers, thickeners, and other ultra-processed additives look nothing like real food, making them hard to digest.

As a result, they feed your gut bacteria, which release gas as they eat.

And too much intestinal gas can cause bloating, stomach pain, and even constipation.

Regularly eating certain food additives can also alter the composition and function of your gut microbiome (North Clin Istanb, 2019).

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

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

⚠️ 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 Added Vitamins and Minerals

Added vitamins and minerals in protein supplements might cause stomach issues too.

Certain micronutrients can affect gut barrier function and immune response, indirectly influencing gastrointestinal health.

In one case, the chronic overconsumption of vitamins (A, selenium, zinc) led to permanent stomach pain (J Int Soc Sports Nutr, 2015).

🚫 Avoid Dairy-Based Proteins

Dairy-based proteins like whey and casein, although not an issue for everyone, can cause stomach issues.

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.

This is particularly true for casein protein, which forms a gel-like substance in your stomach that slows down digestion.

🚫 Avoid Protein Concentrates and Isolates

If you have a sensitive stomach, you might also want to avoid ultra-processed 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 your gut break them down.

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

Studies show that regularly eating protein concentrates and isolates might disrupt your gut microbiome (Nutrients, 2018) and cause the formation of toxic byproducts in your gut (Mol Nutr Food Res, 2024).

Individuals with pre-existing digestion problems should thus look for protein supplements made from whole food protein sources like egg whites and almonds, which are easier to digest and absorb.

Order Samples to see for yourself.

Sources

1. The Biochemical journal (Biochem J). Introduction to the human gut microbiota. 2017.
2. The British journal of nutrition (Br J Nutr). Advantages and limitations of the protein digestibility-corrected amino acid score (PDCAAS) as a method for evaluating protein quality in human diets. 2012.
3. The Journal of nutrition (J Nutr). Amino Acid Intake and Conformance With the Dietary Reference Intakes in the United States: Analysis of the National Health and Nutrition Examination Survey, 2001-2018. 2023.
4. Northern Clinics of Istanbul (North Clin Istanb). Food additives and microbiota. 2019.
5. JGH Open: An Open Access Journal of Gastroenterology and Hepatology (JGH Open). Gut microbiota dysbiosis in functional gastrointestinal disorders: Underpinning the symptoms and pathophysiology. 2021.
6. Journal of the International Society of Sports Nutrition (J Int Soc Sports Nutr). The risks of self-made diets: the case of an amateur bodybuilder. 2015.
7. Nutrients (Nutrients). Effect of a Protein Supplement on the Gut Microbiota of Endurance Athletes: A Randomized, Controlled, Double-Blind Pilot Study. 2018.
8. 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 Registered Dietitian and reviewed by a Physician Assistant. We rely on peer-reviewed research and trusted medical sources, and regularly update our content to ensure accuracy and clarity.