The protein transition: What determines the animal-to-plant (A:P) protein ratios in global diets

Adam Drewnowski ^1* Kayla Hooker ²

• ¹ University of Washington, Seattle, United States
• ² Washington State University Spokane, Spokane, Washington, United States

Several high-income countries have announced plans to reduce the animal-to-plant (A:P) protein ratios in their population diets. The current A:P ratio in those countries is around 65:35, with two thirds of the protein coming from animal sources, meat, eggs, and dairy. Proposals to reduce the dietary A:P protein ratio to 50:50 (France), 40:60 (The Netherlands), or even lower are sometimes referred to as a "healthy protein transition." Using the term "protein transition" may be a misnomer since an opposing and far more important protein transition is currently taking place in the rest of the world. In most low-and middle-income countries (LMIC), the dietary A:P protein ratio is closely associated with, if not determined, by gross national incomes (GNI). As incomes rise, LMIC populations adopt more varied and more nutrient-rich diets with more animal proteins and especially meat. This protein transition, manifested by a strong observed relation between rising incomes and higher A:P protein ratios, follows a well-known principle of economics known as Bennett's Law. Consumer education and regulatory and policy measures aimed at reducing dietary A:P protein ratios worldwide may not uncouple the fundamental relation between powerful economic forces and global diet structures.