How to Find the Best Bariatric Protein Powder

📌 Overview and Key Takeaways

This is a Dietitian’s guide on how to find the best bariatric protein powder.

Discover how to safely supplement your protein intake before and after bariatric surgery.

Last Updated
Jan 27, 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.

Bariatric Protein Powder

Is Protein Powder Good for Bariatric Patients?

Bariatric surgery, also known as weight loss surgery, is a surgical procedure that aims to help people who are severely obese lose weight.

It involves changing the digestive tract to limit the amount of food you can eat and there are different types, including:

• Gastric bypass surgery, which involves creating a small pouch at the top of the stomach and rerouting the small intestine to this pouch
• Sleeve gastrectomy, which involves removing a large portion of the stomach, leaving behind a small sleeve-shaped section
• Adjustable gastric banding, which involves placing an inflatable band around the upper part of the stomach

Bariatric surgery is typically recommended for people who have a body mass index (BMI) of 40 or higher, or a BMI of 35 or higher with other obesity-related health conditions such as diabetes, high blood pressure, or sleep apnea.

It is usually considered a last resort after other weight loss methods, such as diet and exercise, have been exhausted.

Pre-op Diet

A liquid diet is required for bariatric patients 7-14 days before surgery.

It helps reduce the amount of fat around the liver, which is important because your liver sits on top of your stomach where the surgeon will be performing the surgery.

During the pre-op period, protein shakes are a must-have.

Protein is the most satiating (filling) nutrient, so it helps curb cravings and hunger pangs, making the pre-op period more comfortable.

Post-Op Diet

A liquid diet is also required for most bariatric patients about 7 days after surgery.

For the first day or so after surgery, you will only be allowed to drink clear liquids.

Once you can stomach clear liquids, you will be able to add thick liquids (like protein shakes) to your diet.

The “thick liquid” phrase also lasts for about 7 days and getting lots of protein at this time is important for several reasons.

For starters, protein helps with wound healing (Br J Nurs, 2001).

It follows that not eating enough protein post-surgery can compromise your ability to heal.

Research also shows that postoperative protein consumption is linked to long-term weight loss (Obes Surg, 2011).

In other words, a high protein diet can help you reach your ultimate weight loss goals.

Keep in mind that most people should be able to meet their protein needs by eating foods like eggs, fish and meat, but some, especially those with dietary restrictions, may need to supplement their diet.

Protein powder is great because it can be mixed with just milk or water to make a simple protein shake, or added to smoothies, oatmeal, and other recipes.

That said, not all protein powders are created equal.

What is the Best Protein Powder for Bariatric Patients?

As long as you are eating a balanced diet – getting protein from a variety of sources – the type of protein powder you use does not matter.

But ingredients do matter.

In fact, the ingredients in many protein powders can contribute to health problems for bariatric patients.

Among these most problematic ones are food additives and protein concentrates and isolates.

🚫 Avoid Food Additives

Regularly eating emulsifiers, thickeners, artificial sweeteners and other ultra-processed additives can alter the composition of your gut microbiome (North Clin Istanb, 2019).

Over time, this can lead to gut dysbiosis (Microorganisms, 2022), which is linked to a wide range of chronic diseases, including obesity and type 1 diabetes (J Exp Med, 2019).

It follows that bariatric patients with healthy gut microbiomes tend to have better outcomes (Crit Rev Food Sci Nutr, 2023).

⚠️ 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.

Sources

1. British Journal of Nursing (Br J Nurs). The importance of patients’ nutritional status in wound healing. 2001.
2. Obesity Surgery (Obes Surg). Dietary protein intake and bariatric surgery patients: a review. 2011.
3. Northern Clinics of Istanbul (North Clin Istanb). Food additives and microbiota. 2019.
4. Microorganisms (Microorganisms). Gut Microbiota Dysbiosis: Triggers, Consequences, Diagnostic and Therapeutic Options. 2022.
5. The Journal of Experimental Medicine (J Exp Med). The gut microbiome: Relationships with disease and opportunities for therapy. 2019.
6. Critical Reviews in Food Science and Nutrition (Crit Rev Food Sci Nutr). Gut microbiota in bariatric surgery. 2023.
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.