Outside the sumo ring, obesity is not the most pressing problem in generally snake-hipped Japan. It is thus symbolic of Japan’s pharmaceutical industry that Takeda should this week have struck a deal with Amylin Pharmaceuticals, a US biotechnology firm, to develop fat-busting medicines whose main markets will be in wide-girthed America and Europe. With diminishing prospects at home, Japanese pharmaceutical companies have little option but to scour the globe for richer pickings.

This week’s deal involves a modest upfront payment of $75m to secure Amylin’s pipeline of anti-obesity drugs. The Japanese company will fork out far bigger sums to test and develop Amylin’s medicines as they move towards a place on the pharmacy shelf.