Question: If are trend of keeping clean is too keep up. what do you think will become of the future of less devoelped and more developed countries?

Mark Fogg answered on 16 Jun 2010:

The ‘Hygiene Hypothesis’ suggests there could be more allergies in the developed world and initially, fewer people dying from disease in the under developed world. Eventually, as hygiene improves in the under developed world, I suspect there will be more allergies there too.
Fortunately, science is helping us understand what’s happening. We will hopefully be able to get the balance right, between fighting disease through good hygiene and being too obsessed, thereby causing allergies. After all, cleanliness is not all bad, you wouldn’t want to go back to the days when you die of diseases like Typhoid or Cholera, or were smelly all the time, would you?