Plant-based diets are traditional in developing countries: 21st century challenges for better nutrition and health

The chronic degenerative diseases were virtually unknown in original hunter-gatherer societies. At the dawn of the 21st century, however, they represent the most important public health challenge to populations of both the industrialized, affluent nations of the temperate zones and the low-income developing countries of the tropics. The developing countries most closely reflect the legacy of our traditional foreparents while constituting three-quarters of the world's populace and public health interest. For economic, traditional, religious and cultural reasons, the majority of the dietary fares in the developing world are largely plant based. This is associated with high prevalences of deficiency states in vitamin A, iron, zinc, riboflavin and vitamin B12. Poor linear growth and chronic energy deficiency are concomitant conditions. Conversely, the major chronic diseases have low prevalences among the rural peasantry and tribal groups, with the exception of gastro-esophageal cancer, osteoarthritis and cataract. As a site for intensive research in food and nutritional sciences, Guatemala provides important lessons about the origin and evolvement of a congruent plant-based diet within a food system and which factors of demographic expansion, urbanization, environmental stress and food technology will carry it through the 21st century. We can conclude that, whatever was the 'original' dietary pattern of pre-agricultural humankind, a plant-based diet regimen provides the lowest content of promoters and the highest content of inhibitors of metabolic dysregulation that lead to the major causes of disease and debility in adults over 40 years of age. For developing countries, the challenge is to maintain and reinforce the traditional eating patterns while improving their delivery of micronutrients and obviating any adverse environmental consequences in their traditional preparation patterns. For developed countries, there is an opportunity to find a 'road map' of guidelines to allow correction of current, pathogenic dietary and lifestyle patterns by examining the food-ways of traditional developing societies' cuisines.