What are the ingredients in Protein One?

December 21, 2025 •

3 min read

Protein One bars and powders are known for being keto-friendly and low in sugar. The ingredients in Protein One products vary by flavor and product type, but typically feature a blend of different protein sources, sweeteners, and fibers to create a low-calorie, high-protein snack.

Quick Summary

A detailed look at the core ingredients found in Protein One bars and powders. Explore the different protein sources, such as whey and soy isolates, along with key fillers, fibers, and sweeteners that give them their unique nutritional profile.

Key Points

Protein Blend: Protein One products use a mix of whey protein isolate, soy protein isolate, and milk protein concentrate for a balanced protein profile.
Low-Sugar Sweeteners: Instead of high sugar, they use sugar alcohols like maltitol and erythritol, along with stevia extract, for sweetness.
High in Fiber: Chicory root extract is a primary ingredient that provides a significant source of dietary fiber, contributing to fullness.
Binders and Oils: Ingredients such as vegetable glycerin, palm kernel oil, and soy lecithin are included to give the bars their chewy texture and shelf stability.
Flavor Specific Additions: Other ingredients like cocoa powder, natural and artificial flavors, and fruit powders are added to create the product's specific flavor profile.
Allergen Warning: The products typically contain milk and soy, and may have cross-contamination warnings for other common allergens.
Keto-Friendly Formulation: By utilizing fiber and sugar alcohols, Protein One products are formulated to be low in net carbs, which aligns with ketogenic diet principles.

Core Protein Sources

Protein One products primarily utilize a blend of dairy and plant-based proteins. This typically includes:

Dairy-based Proteins

Whey Protein Isolate: A rapidly absorbed protein.
Milk Protein Isolate: Provides both whey and slower-digesting casein.
Calcium Caseinate: A form of casein known for its slow digestion, contributing to satiety.

Plant-based Proteins

Soy Protein Isolate: A complementary protein source that also impacts texture.

Sweeteners and Sugar Alternatives

To achieve a low sugar content while maintaining sweetness, Protein One incorporates various sugar substitutes:

Maltitol Syrup & Erythritol: Sugar alcohols providing sweetness with fewer calories than sugar, though potentially causing digestive issues in some.
Stevia Extract: A natural, calorie-free sweetener often used with others for balanced flavor.
Sucralose: A highly potent artificial sweetener found in some versions, particularly the Protein One Max line.
Allulose: A low-calorie rare sugar featured in some keto-friendly bars.

Fibers and Binders

Fiber is crucial for texture and promoting fullness:

Chicory Root Extract: A significant source of dietary fiber and a prebiotic, aiding digestion and adding bulk.
Vegetable Glycerin: Acts as a binder and humectant, keeping bars moist.

Other Additives and Flavorings

Additional ingredients contribute to flavor, texture, and stability:

Palm Kernel Oil: Used for fat content and texture, especially in coatings.
Soy Lecithin: An emulsifier preventing ingredient separation.
Collagen: Adds chewiness and protein in some bars.
Cocoa Powder: Provides chocolate flavor in relevant varieties.
Natural and Artificial Flavor: Used to create diverse flavor profiles.

Ingredient Comparison: Protein One Bars vs. ONE Bars

Comparing Protein One to ONE Bars reveals some key differences in their formulations for similar flavors:


Ingredient Category	Protein One Bars (e.g., Chocolate Chip)	ONE Bars (e.g., Chocolate Chip Cookie Dough)
Primary Proteins	Soy Protein Isolate, Whey Protein Isolate, Whey Protein Concentrate, Calcium Caseinate	Protein Blend (Whey Protein Isolate, Milk Protein Isolate)
Fibers	Chicory Root Extract, Allulose	Isomalto-Oligosaccharides (Prebiotic Fiber)
Sweeteners	Maltitol Syrup, Stevia Extract, Allulose	Maltitol, Sucralose
Fats	Palm and Palm Kernel Oil, Canola Oil	Palm Kernel Oil, Sunflower Seed Butter
Emulsifiers	Soy Lecithin	Soy Lecithin, Sunflower Lecithin

Conclusion: A Look at the Overall Composition

Protein One products are formulated to be low-calorie, high-protein snacks with minimal sugar, utilizing a blend of protein isolates, sugar alcohols, stevia, and fiber from sources like chicory root extract. While effective for protein supplementation and managing sugar intake, the presence of sugar alcohols may cause digestive discomfort for some. Consumers should always review the specific ingredients list for the most accurate information on their chosen product.

For a general guide on how to evaluate different protein bar options, see this article by Health.com: Are Protein Bars Actually Healthy? Here's How to Pick the Best Ones for Your Goals.

What are the ingredients in Protein One? A breakdown of what's inside your snack.

Primary Protein Sources: Whey, soy, and milk protein isolates form the foundation for muscle support.

Sweeteners and Fiber: Maltitol, stevia, and chicory root extract provide low-calorie sweetness and fiber content.

Additives and Fats: Palm kernel oil and soy lecithin are included for texture, moisture, and binding.

Allergen Information: Contains milk and soy; may be manufactured on equipment that processes other allergens like peanuts.

Nutritional Comparison: Formulation differs slightly by flavor and whether it's a bar or powder.

Read the Label: Always check the specific packaging for the most accurate and up-to-date information.

Potential Side Effects: Large amounts of sugar alcohols can cause digestive discomfort in some people.

How Ingredients Impact Nutrition: The combination of protein, fiber, and low sugar contributes to its keto-friendly profile.

Frequently Asked Questions

The main source of protein in Protein One products is a blend of dairy and plant-based isolates, including whey protein isolate, soy protein isolate, and milk protein isolate.

Yes, Protein One bars are formulated to be low in sugar, typically containing only 1 gram per bar. The sweetness comes from sugar alcohols like maltitol or erythritol and natural sweeteners like stevia extract.

Protein One uses chicory root extract as a key source of dietary fiber. This prebiotic fiber adds bulk, aids digestion, and contributes to the bar's chewy texture.

Yes, Protein One uses a combination of sweeteners. While they use stevia extract, many products also contain artificial sweeteners like sucralose or sugar alcohols such as maltitol and erythritol.

People with allergies should carefully check the label. Protein One products contain milk and soy. They may also have cross-contamination warnings for other ingredients like wheat, peanuts, or tree nuts, depending on the flavor and manufacturing process.

Vegetable glycerin is included as a humectant and binder. It helps to maintain the bar's moisture and chewy consistency over time, preventing it from drying out.

Yes, some Protein One bar flavors, particularly certain versions of the 90 Calorie bars, list collagen as an ingredient. It is used to contribute to the texture and protein content.