现在,一方面由于信息革命和技术革命,人们已经从繁重的体力劳动中解放出来,活动量明显地减少;而另一方面,由于人类生活水平的不断提高,出现营养过剩的情况.如果对饮食缺少合理的限制,人的体重自然就会增加,以致肥胖已成为一种世界性的流行病. Now, on the one hand, because of the information revolution and the technological revolution, people have liberated themselves from heavy physical labor and their activity has been significantly reduced. On the other hand, due to the continuous improvement of human living standards, there has been an oversupply situation. Without reasonable restrictions, people’s weight will naturally increase, so that obesity has become a worldwide epidemic.