The Diet, Health, and Environment Trilemma

As populations become more affluent and urbanized, diets are shifting such that they are becoming higher in calories and include more highly processed foods and animal products. These dietary shifts are driving increases in diet-related diseases and are also causing environmental degradation. These linked impacts pose a new key issue for global society—a diet, health, and environment trilemma. Recent dietary shifts have contributed to increasing diet-related health and environmental impacts, including an 80% increase in global diabetes prevalence and an 860% increase in global nitrogen fertilizer use. Furthermore, if current dietary trajectories were to continue for the next several decades, diet-related diseases would account for three-quarters of the global burden of disease and would also lead to large increases in diet-related environmental impacts. We discuss how shifts to healthier diets—such as some Mediterranean, pescetarian, vegetarian, and vegan diets—could reduce incidence of diet-related diseases and improve environmental outcomes. In addition, we detail how other interventions to food systems that use known technologies and management techniques would improve environmental outcomes.