How many people would believe a doctor who says eating two packages of natto fermented soybeans every day helps you lose weight?

A responsible doctor would never make such a claim. But when popular TV show host Masaaki Sakai said just that in early January, citing academic findings and comments from "experts," while guest commentators "oohed" and "aahed" at data that reported remarkable weight losses, tens of thousands of viewers believed it. The sticky, smelly stuff began to fly off store shelves nationwide, prompting two major natto makers to issue apologies for not keeping up with demand.

Then came the real shocker. A couple of weeks later, the Osaka-based Kansai Telecasting Corp., which produces the popular health and entertainment show "Hakkutsu! Aruaru Daijiten II (Encyclopedia of Living II)" announced that the show's producers had faked the test results and altered experts' comments to make out that natto was a slimming product. In the days that followed, it was exposed in other media that the show had a history of making things up. It had, for example, claimed that lettuce induced sleep, miso soup helped weight loss and wasabi made you younger.