BEIJING — Older people in China remember the Great Famine of 1958-61, when 15 million to 45 million people died of hunger and related causes.

Today, nearly every street corner in Beijing and many other cities seems to boast a McDonald’s. There are KFC outlets in almost every Chinese city, 3,700 in all. Meanwhile, newly minted members of the Chinese middle class have rushed to buy cars, leaving bicycles that were once a major source of exercise rusting on the street.