In Japan, being thin isn't just the price you pay for fashion or social acceptance. It's the law.

So before the fat police could throw her in pudgy purgatory, Miki Yabe, 39, a manager at a major transportation corporation, went on a crash diet. In the week before her company's annual health check-up, Yabe ate 21 consecutive meals of vegetable soup and hit the gym for 30 minutes a day of running and swimming.

''It's scary,'' said Yabe, who is 160 centimetres tall and weighs 60 kilograms. ''I gained two kilos this year.''

In Japan, already the slimmest industrialised nation, people are fighting fat to ward off dreaded metabolic syndrome and comply with a government-imposed waistline standard.

Metabolic syndrome, known here simply as ''metabo'', is a combination of health risks, including stomach flab, high blood pressure and high cholesterol, that can lead to cardiovascular disease and diabetes.