The nationally broadcast programme made by Kansai Telecasting (KTV) set off a craze for natto, a notoriously smelly and slimy delicacy consisting of fermented soya beans. The programme, Revealed! Encyclopaedia of Life, presented evidence that a diet including two servings of natto a day would cause substantial weight loss in two weeks.

Supermarket shelves were emptied and natto makers struggled to keep up with the surge in demand. Now the deception has been exposed by a weekly news magazine and KTV has admitted that it faked the results of blood tests and mistranslated the words of an American scientist who appeared in the programme.

At the peak of the boom, demand increased threefold and natto suppliers took out advertisements in newspapers apologising to customers for the shortage. Now they are left with a surplus of rotting soya beans. “Today the orders have suddenly stopped,” one supermarket told the Mainichi newspaper. “We’ve already produced natto but it has only a one-week use-by date. If we don’t receive any orders we might have to dispose of it. We could lose hundreds of thousands of yen.”

Another natto dealer said: “We ordered a huge number of natto containers and boxes for shipments, but they might not fit in the warehouse. The television station caused trouble for supermarkets, industry workers, consumers and lots of other people.”

Yesterday Japan’s Internal Affairs and Communications Ministry summoned KTV executives to a meeting to determine whether charges should be brought against the broadcaster.

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