Can Protein Powder Cause Gallstones​?

📌 Overview and Key Takeaways

Can protein powder cause gallstones​?

This is a Dietitian’s guide on how to supplement your protein intake without causing cholelithiasis or gallstone attacks.

Last Updated
Feb 24, 2026

Author and Medical Reviewer

Written by Kayla Kamen, MS, RD

Kayla Kamen is a Registered Dietitian with a MS in Nutrition.

Medically reviewed by Jennifer Fossett, PA-C

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

Protein Powder for Gallstones

Can Protein Powder Cause Gallstones​?

Gallstones are hardened deposits that form inside your gallbladder, which is a small organ located under your liver that stores and releases bile – a digestive fluid that helps you break down fats.

The presence of gallstones is known as cholelithiasis and most people (70-80%) with cholelithiasis have no symptoms (“silent gallstones”).

But gallstones can move and block bile flow, triggering painful side effects such as stomach pain, nausea, and vomiting.

The formation of gallstones is associated with metabolic risk factors such as obesity and insulin resistance, as well as diets high in refined sugars, saturated fats, and low in fiber.

Protein powder does not directly cause gallstones.

In fact, studies indicate that neither total dietary protein intake nor type of dietary protein is associated with gallstone formation, including in high-risk populations such as pregnant women (JPEN J Parenter Enteral Nutr, 2015).

But even though protein powder consumption itself is not a direct cause, it could still contribute indirectly to gallstone formation in certain situations:

• Rapid Weight Loss: High-protein diets and protein supplements are often associated with rapid weight loss, which can increase the risk of gallstone formation because the liver secretes extra cholesterol into bile when the body burns fat quickly.
• Artificial/Ultra-Processed Ingredients: Many protein powders contain emulsifiers, thickeners, and other ultra-processed and/or artificial additives that can worsen digestive symptoms.
• Low Fiber Intake: If protein powders replace balanced meals, fiber intake might drop, which can lead to poor digestion and bile imbalances.

It follows that it is important to be mindful of your protein powder intake, in terms of both how you use it, and what is in it.

What Is the Best Protein Powder for Gallstones?

Not all protein powders are created equal.

As you just learned, some contain ingredients known to exacerbate gallstone attacks.

They can also cause long-term gut health problems, which could contribute to the formation of gallstones.

Among top offenders are food additives and protein concentrates and isolates.

🚫 Avoid Food Additives

Regularly eating emulsifiers, thickeners, and other additives can alter the composition and function of your gut microbiome (North Clin Istanb, 2020).

These shifts, known as gut dysbiosis, have been shown to alter bile acid metabolism, cholesterol absorption, and the enterohepatic circulation (Pharmacol Ther, 2022), all of which are mechanistically linked to cholelithogenesis (World J Gastroenterol, 2023).

Moreover, multiple studies demonstrate that shifts in gut microbial composition are associated with gallstone disease (Front Med (Lausanne), 2025).

⚠️ 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 Protein Concentrates and Isolates

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 and cause the formation of toxic byproducts in your gut (Nutrients, 2018; Mol Nutr Food Res, 2024).

You 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.

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.

Sources

1. JPEN. Journal of Parenteral and Enteral Nutrition (JPEN J Parenter Enteral Nutr). Dietary fat and protein intake are not associated with incident biliary sludge and stones during pregnancy. 2015.
2. Northern Clinics of Istanbul (North Clin Istanb). Food additives and microbiota. 2020.
3. Pharmacology & Therapeutics (Pharmacol Ther). Bile acid metabolism and signaling, the microbiota, and metabolic disease. 2022.
4. World Journal of Gastroenterology (World J Gastroenterol). Gastrointestinal microbiome and cholelithiasis: Current status and perspectives. 2023.
5. Frontiers in Medicine (Front Med (Lausanne)). Advances in research on the role of gut microbiota in the pathogenesis and precision management of gallstone disease. 2025.
6. Nutrients (Nutrients). Effect of a Protein Supplement on the Gut Microbiota of Endurance Athletes: A Randomized, Controlled, Double-Blind Pilot Study. 2018.
7. 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.