I guess bananas in Japan aren't expensive enough to keep a new diet craze from making them scarce:
The Morning Banana Diet regime is simple: A banana (or as many as you want) and room temperature water for breakfast; eat anything you like for lunch and dinner (by 8 p.m.). A three o'clock snack is okay, but no desserts after meals, and you have to go to bed before midnight. Sumiko Watanabe, a pharmacist in Osaka designed this stress-free diet to help increase the metabolism of her husband Hitoshi Watanabe, who had been rather overweight. In due course, Mr. Watanabe lost 37 pounds and introduced the diet on mixi, one of Japan's largest social networking services.
I'd gladly trade them 100 pounds of bananas for 100 pounds of sashimi grade fish... think I can cash in before the craze fades?