Women not just in the United States but the rest of the industrialized world are getting fatter and fatter, while Japanese women are experiencing the opposite effect, why? Even though many Japanese women have the ideal bmi they still see themselves as overweight;

“I am quite fat, actually,” said Michie Takagi, a 70-year-old grandmother and retired clothing store executive. She has a body mass index (BMI) of 19.9, which is at the thin end of normal. While the average American woman has gained about 25 pounds over the past 30 years, Takagi has gained 4.5 pounds, typical for her age cohort in Japan, according to U.S. and Japanese government figures.

Japan is a bit odd, unlike most countries where women and men have been packing more pounds over the years the trend is reversed in Japan.

Skinnier still are Japanese women younger than 60, who were thin by international standards three decades ago and who, taken as a group, have since been steadily losing weight.

The trend is most pronounced among women in their 20s. A quarter-century ago, they were twice as likely to be thin as overweight; now they are four times more likely to be thin. For U.S. women of all ages, obesity rates have about doubled since 1980, rising from 17 percent to 35 percent.

The reasons for  the small percentage of overweight women is simple, social pressure:

women looking critically at other women — is the most important reason female skinniness is ascendant in Japan, according to Hisako Watanabe, a child psychiatrist and assistant professor of pediatrics at the Keio University School of Medicine in Tokyo.

“Japanese women are outstandingly tense and critical of each other,” said Watanabe, who has spent 34 years treating women with eating disorders. “There is a pervasive habit among women to monitor each other with a serious sharp eye to see what kind of slimness they have.”

Although Japanese women have been getting skinner the opposite has occurred for Japanese men and children;

Adult men and children of both sexes are gaining weight at a pace that worries the government. A quarter-century ago, 20 percent of men in their 50s were overweight; now, 32 percent are.

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