CAMBRIDGE, United Kingdom — Consumers are increasingly confronted with competing claims about which protein sources are healthiest, most sustainable, and best value for money. A new study published in Frontiers in Sustainable Food Systems argues that existing food labels tell only part of the story and introduces a new multidimensional framework designed to evaluate protein sources more holistically.
Developed by Dr. Chris Macdonald of the University of Cambridge, the new scoring system combines measures of environmental impact, health, affordability, and availability into a single framework for comparing high-protein foods.
Applying scoring system to 20 commonly consumed protein-rich foods, the analysis found a striking pattern: every product in the highest-scoring quintile was plant-based, while every product in the lowest-scoring quintile was animal-based. T ofu ranked first overall, while cheddar cheese ranked last. E
Looking beyond single-issue food labels
The paper argues that many existing food rating systems focus on only one aspect of a product. While useful, these single-dimension labels can obscure important trade-offs and make it difficult to compare foods comprehensively.
Rather than proposing another front-of-package label, the author describes the BPI Score as a decision-making framework intended to improve food literacy among consumers, policymakers and organizations.
Measuring people and planet together
An environmental subcategory incorporates greenhouse gas emissions, water pollution, land use and freshwater use, standardised per 100 grams of protein to enable fair comparisons across foods. The analysis found particularly large environmental differences between many plant- and animal-based protein sources. For example, the paper reports that beef generated substantially higher greenhouse gas emissions and required much more land than tofu when compared on an equivalent protein basis.
A 'people' subcategory combines nutritional considerations (including sodium, saturated fat, cholesterol and whether a food provides all essential amino acids) with measures of affordability and supermarket availability.
As noted in the paper, “Against deliberate corporate obfuscation and marketing myths, the goal of a holistic score is not to create a new label, but to foster a new literacy, one that empowers us to see the reality of the systems we are funding.
Ultimately, beyond the spreadsheets and scores, lies a fundamental reckoning: our protein choice is a referendum on the compassion we are willing to show to animals, to the planet, and to future generations.”
Journal
Frontiers in Sustainable Food Systems
Article title
"What are the best sources of protein? Introducing the BPI Score"
Author
Dr Chris Macdonald. Fellow at Lucy Cavendish College, University of Cambridge. Director of the Better Protein Institute.
Link to article
https://www.frontiersin.org/journals/sustainable-food-systems/articles/10.3389/fsufs.2026.1677796/full
DOI
https://doi.org/10.3389/fsufs.2026.1677796
Contact
Chris.Macdonald@lucy.cam.ac.uk
Method of Research
Systematic review
Subject of Research
Food
Frontiers in Sustainable Food Systems
Commentary/editorial
People
What are the best sources of protein? Introducing the BPI Score
29-Jul-2026
The author(s) declared that this work was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.