Where did the health crisis begin?

What are the causes of the health crisis in China? In the twenty years from 1982 to 2002, the metabolic syndrome of China residents can go from "zero" to "the first in the world"? Is it a genetic change? No The genes of a species cannot be fundamentally changed in a few decades; Is it overnutrition? Not really; The health status of people in China is unbalanced nutrition and excessive poisoning. In fact, most of the foods we eat now are not only nutritious but also toxic besides providing calories!