Tofu has just been crowned the highest-ranked protein source in a new scientific scoring system from researchers at the University of Cambridge. The BPI Score, published in Frontiers in Sustainable Food Systems in July 2026, evaluated 20 high-protein foods according to their impacts on both people and the planet. Tofu came first with a score of 36, while plant-based proteins occupied every position in the top quintile. Cheddar cheese ranked last.
So what makes tofu so exceptional?
First, protein quality. Soy is one of the few plant foods that naturally provides all nine essential amino acids. Research assessing digestibility has found tofu protein to be highly digestible, with one study measuring approximately 95% true ileal amino-acid digestibility. A 2024 study also found tofu had a DIAAS of 79–91 depending on the soybean cultivar and preparation.
But the Cambridge research went beyond simply asking, “How much protein does this food contain?” Its People Score considered nutritional characteristics such as sodium and saturated fat alongside affordability and accessibility. Tofu received the highest People Score. Its Planet Score was also the highest, reflecting exceptionally low greenhouse-gas emissions, land use and water pollution compared with many animal-derived proteins. For example, the study cites tofu at 0.61 kg CO₂e per 100 g of protein, compared with 64.19 kg for beef.
This matters because what we eat isn’t just a question of personal nutrition. Food is simultaneously a health issue, an environmental issue and an animal issue.
A growing body of research associates healthier plant-based dietary patterns with lower risks of cardiovascular disease, type 2 diabetes, cancer and premature death. A 2023 systematic review and meta-analysis covering 37 publications from 24 cohorts found that replacing animal foods with plant foods was associated with better cardiometabolic outcomes and lower mortality.
Then there is the planet. Animal agriculture is a major driver of greenhouse-gas emissions, land use, freshwater use and pollution. Major food-system research has repeatedly identified dietary shifts towards plant-based foods as an important part of reducing these pressures.
And finally, the animals.
The BPI Score did not include animal welfare in its first version — something its author explicitly acknowledges. But for anyone who considers animals individuals rather than commodities, that omission is enormous. Scientific research increasingly recognises sentience across farmed mammals, birds and aquatic animals, while intensive farming can prevent animals from expressing behaviours that matter to their wellbeing.
So perhaps the most powerful thing about tofu isn’t simply that it can build muscle.
It’s that we can obtain the protein we need without requiring an animal to become the protein source.
Healthier choices. Lower environmental impact. And, most importantly, a food system capable of recognising that animals are someone — not something.