Scientists sniffing out the Western allergy epidemic

But generations before did not suffer from this epidemic, so what is it that's making us so allergic in our modern world? Many theories have come and gone over the years, but now scientists think they may have discovered what's to blame - and BBC Two's Horizon has put this theory to the test, BBC News reports. Every one of us is covered head to toe with bacteria, and intriguingly scientists believe these microscopic bugs are the key to explaining why we are becoming more allergic. Families under the microscope The bacteria that cover our skin, line our mouths and fill our guts not only outnumber our own cells by about 10 to one but may play a vital role in training our immune systems. Changes to our lifestyles are influencing these microorganisms, and allergies are the consequence. To see if this theory played out in the real world, Horizon put the lives of two allergic families under the microscope. In one of the families, eight-year-old Joe suffers from severe asthma, hay fever, eczema, and nut, pet and dust mite allergies. In the other, four-year-old Morgan's list of allergies is seemingly endless. Along with severe eczema and hay fever, he is allergic to dairy products, nuts, soya, kiwi fruit, avocado, banana, latex, cats, dogs and horses. Both families gamely agreed to provide bacterial swabs of their skin, guts and even their homes in the hope they might offer clues about why they suffer from allergies.