Recently some American scientists have given a useful piece of advice to people in industrialized nations. They say people should eat more of the same kind of food eaten by humans living more than 10,000 years ago. ___71___
The scientists say that the human life has changed greatly. Our bodies have not been able to deal with these changes in lifestyle and this had led to new kinds of sickness. ___72___ So they are called “disease of civilization”. Many cancers and diseases of the blood system are examples of such diseases.