In a paper published in Frontiers in Sustainable Food Systems, Dr. Chris Macdonald explored the best sources of protein currently available.
To answer the question, Macdonald had to build a new holistic scoring system that combines measures of environmental impact, health, affordability and availability into a single framework.
Applying the 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. Tofu ranked first overall, while cheddar cheese ranked last.
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.
TOFU DOMINATION
Link to open access article https://www.frontiersin.org/journals/sustainable-food-systems/articles/10.3389/fsufs.2026.1677796/full



Well, if I had to guess, I’d say they started with the result they wanted, and worked backward from there.
I haven’t read the article and I’m not saying you’re wrong, but in general plant foods are known to have less environmental impact than animal products because animals are higher on the food chain, and it takes more energy to raise an animal for consumption (including the resources to grow food for the animal) than to just grow plants and consume them directly.