Protein quality has long been defined by how efficiently a protein supports growth, favoring animal sources due to their complete amino acid profile. However, this metric was shaped by outdated research, industry influence, and a narrow focus on growth rather than long-term health. While plant proteins are often labeled as “lower quality” due to slightly lower digestibility and amino acid content, they may actually be more beneficial for longevity by promoting metabolic health and reducing disease risk.

The real issue may not be protein inadequacy but the underconsumption of protective plant foods, challenging the conventional wisdom that prioritizes protein quantity over overall dietary quality.