A recent article in the Guardian on the Pacific island nation of Nauru causes Dalrymple to recall his visit there in the 1980s:

When I visited it all those years ago it had become immensely rich because of the phosphate rock that covered its surface…Not more than twenty years before, the inhabitants had lived by subsistence on fish and coconuts, but now they had one of the highest per-capita incomes in the world.

This sudden accession to wealth was not altogether a good thing for the local population (4,000 when I visited, 10,000 now). There was little for them to do, either in the way of work or entertainment. Practically everything—rent, telephone, electricity, water—was supplied to everyone free of charge. One of the major occupations of the population was eating, which it did on a vast scale. Many Nauruans became enormously fat…

This is all explained in greater (and very entertaining) detail in his second book, Fool or Physician: The Memoirs of a Sceptical Doctor.