During the past two decades, China has been rapidly changing from a mostly agrarian environment of food production and consumption to a more urban environment typically found in Western industrialized societies.

This means transitioning from a simple diet mainly comprised of a few locally-produced plant-based foods to a diet comprised of significantly more animal-based foods. Such a poor-to-rich transition leads to more food variety, more food availability (i.e., more calories), more total and animal-based protein and more total fat.

It also means less dietary fiber and antioxidants, almost exclusively found in plant-based foods. When transition opportunities arise in poor societies, there is a tendency to desire foods having nutritional characteristics typically found in rich Western industrialized societies in order to minimize or eradicate the diseases generally associated with poverty.

These 'diseases of poverty' are mostly infectious and communicable, like tuberculosis, pneumonia and parasitic diseases, among others. It has been well established that these diseases occur primarily because of poor sanitation and secondarily because of poor nutrition resulting from an inadequate consumption of calories (total food), protein and certain vitamin and mineral micronutrients.