Home Hygiene & Health
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Module 4 - Are we too clean for our own good?

What are the origins of this idea?

In proposing the hygiene hypothesis, Strachan suggested  that lower incidence of  childhood infections could explain the 20th century  rise in allergies. This was based on studies showing that larger family size appeared to protect against hay fever. 

Strachan suggested that smaller families provided insufficient microbial exposure because of less person to person spread of infection – but also because of “improved household amenities and higher standards of personal cleanliness”

From this the notion that “we have become too clean for our own good” has arisen

Experts agree

Most experts now agree that the “hygiene” hypothesis is a misnomer.

Whilst the link between microbial exposure and inflammatory disease is probably correct, the idea that children who have more infections are less likely to develop allergies is now largely discounted.

This means that allergies are not the price we have to pay for freedom from infectious diseases

Respiratory infections can actually increase allergy risks

There is now evidence that childhood infections, far from protecting, actually increase the risk of allergies