日本是世界上人均寿命最长的国家。然而在20世纪20年代,日本人的平均寿命也不过45岁。在30年代后,日本人的平均寿命逐渐增长,到20世纪末,男性平均寿命已达到76.4岁,而女性更是高达8l岁以上。不到一个世纪,日本便从低寿国家跃升为长寿国。那么这是什么缘故呢?经国外专家进行的大 Japan is the country with the longest life expectancy per capita in the world. However, in the 1920s, the average life expectancy of Japanese people was only 45 years. After the 1930s, the average life expectancy of Japanese people gradually increased. By the end of the 20th century, the average life expectancy of men has reached 76.4 years, while that of women has reached as high as 81 years. In less than a century Japan leapt from longevity to longevity. So what is the reason? The large by foreign experts