Protein Bars and the Digestibility Dilemma: Are You Really Getting the Protein You Paid For?

Protein bars have long been marketed as a convenient and nutritious way to boost protein intake, especially for fitness enthusiasts and busy professionals. However, a recent study has uncovered a surprising issue: many protein bars may not be as digestible as their labels suggest.

In Short

• A study examines protein bar digestion.
• Over 81% met high-protein label standards.
• Full bars have lower digestibility than milk-based proteins.

The Study and Its Findings

Researchers at the Hungarian University of Agriculture and Life Sciences examined data from OpenFoodFacts.org on 1,600 protein bars. Although 81% met the EU’s "high in protein" criteria—requiring at least 20% of their calories from protein—the study raised concerns about their digestibility.

But when researchers simulated how our bodies digest these bars, they uncovered an important drawback.

Scientists evaluated protein quality by testing four protein bars with different sources: plant-based (pea and rice), animal-based (milk), and two mixed-source varieties combining milk, egg, collagen, and soy. Using a digestion simulation, they discovered that even bars with high-quality proteins exhibited reduced digestibility when consumed as a complete product.

Why Digestibility Matters

In simple terms, digestibility refers to how well your body can break down and absorb the protein you eat. The study revealed that ingredients like sugars, fats, and fibers—added to enhance texture and taste—may hinder the absorption of essential amino acids. Even the best-performing bar, composed entirely of milk proteins, fell below the Food and Agriculture Organization’s (FAO) recommended threshold for high protein quality.

What This Means for Consumers

While protein bars remain a convenient snack, experts caution against relying on them as a primary protein source. Instead, consumers should look beyond the label and consider the type and digestibility of the protein they are consuming. Whole food sources such as lean meats, dairy, eggs, and legumes may offer better protein absorption and nutritional benefits.

Researchers suggest that sugars, fats, and fibers—added for texture and taste—may hinder amino acid absorption.

The Call for Clearer Labeling

The findings emphasize the importance of stricter standards and more transparent labeling for protein claims in processed foods. As consumers become more aware of digestibility issues, manufacturers may need to rethink their formulations to ensure their products truly deliver the promised nutritional value.

In the meantime, the best approach is to diversify protein sources and prioritize whole foods for optimal health and muscle recovery.

The study questions how we assess protein-rich foods, warning against overreliance on protein bars. Consumers should look beyond the label. "It's not just about how much protein a bar contains. The type and digestibility of that protein matters too," the researchers said.

Conclusion

The recent study sheds light on an important issue in protein bars: Digestibility. While many products meet labeling standards for being "high in protein," their actual digestibility and absorption fall short. Additional ingredients like sugars, fats, and fibers may hinder the body's ability to fully utilize the protein, raising concerns about their nutritional value.

This research emphasizes the need for clearer labeling and more transparent assessments of protein quality in processed foods. Until stricter standards are introduced, consumers should focus on whole food sources for optimal protein intake, ensuring they get the nutrients their bodies truly need.

References:

1. Mackie, Alan. "Insights and gaps on protein digestion." Current Opinion in Food Science 31 (2020): 96-101. https://www.sciencedirect.com/science/article/abs/pii/S2214799320300254

2. Samuel, Kerenhappuch Susan, and Nazni Peerkhan. "Pearl millet protein bar: nutritional, organoleptic, textural characterization, and in-vitro protein and starch digestibility." Journal of Food Science and Technology 57, no. 9 (2020): 3467-3473. https://link.springer.com/article/10.1007/s13197-020-04381-x

3. AlJaloudi, Rawan, Maher M. Al-Dabbas, Hani J. Hamad, Rawan A. Amara, Zaher Al-Bashabsheh, Mahmoud Abughoush, Imranul H. Choudhury, Bha’A. Aldin Al-Nawasrah, and Sehar Iqbal. "Development and characterization of high-energy protein bars with enhanced antioxidant, chemical, nutritional, physical, and sensory properties." Foods 13, no. 2 (2024): 259. https://www.mdpi.com/2304-8158/13/2/259

(Input from various sources)

(Rehash/Mradula U Naik/MSM)