It’s one of those questions that seems to rear its ugly head about this time every year. Especially by those who swear that they have never before had hayfever and have suddenly found themselves with watery, itchy eyes and constant sneezing. Here we ask, is hayfever really getting worse? And could the reason be that we are just too clean?
Hayfever – the facts
Hayfever or seasonal allergic rhinitis is an immune reaction to allergens, with pollen being the most common cause. It usually results in inflammation of the nasal mucous membranes and symptoms include sneezing, watery eyes and an itching, drippy nose when sufferers come into contact with their allergy triggers.
Current research from the National Aerobiology Research Unit suggests a significant increase in the incidence of seasonal allergies over the last twenty years.
So what’s causing this increase?
• Researchers suggest that urbanisation as well as increasing environmental pollution can increase susceptibility to hayfever, or environmental sensitivity
• Overall shifts in global weather patterns negatively affect urban areas because consistently high humidity levels cause pollens to remain low to the ground, which causes further respiratory aggravation for allergy sufferers
• The hygiene hypothesis – is our society becoming too clean?
The ‘hygiene hypothesis’
Our environment has become increasingly sterile with hand sanitisers, wipes and anti bacterial sprays galore. Our overly clean environment however is causing real problems for our immune systems, which are struggling to differentiate between real threats and harmless things like pollen and dust-mites.
Immunologist Professor Graham Rook recently commented that people’s allergies have got worse because we no longer have the same exposure to dirt. In the 19th century, he says, farm workers rarely suffered from hayfever. “Sophisticated townies were more likely to get it. Summer sneezing was a sign of culture.”
Numerous studies have provided very compelling evidence that your body actually benefits from regular exposure to dirt. Being exposed to a bit of bacteria means that the immune system can do what it’s supposed to: develop a tolerance to it.
This is what has been found so far:
• NHS Digital data shows that there were over 29,500 hospital admissions for allergic reactions in 2015-16 compared to 22,200 in 2011-12. Doctors say that rising levels of cleanliness and living in a much cleaner world are lowering people's natural resistance to substances such as dust and pollen.1
• Children who grow up in extremely clean homes are more likely to develop asthma and hayfever than children who grow up on farms or in houses with a little bit of dirt, according to a 2002 study in The New England Journal of Medicine.
• Children who are overly hygienic are at an increased risk of developing wheezing-- a symptom of asthma -- and eczema. A study in the Archives of Disease in Childhood found that children with the highest degree of personal hygiene -- those who washed their faces and hands more than five times per day, cleaned before meals, and bathed more than two times each day -- were the most likely to develop eczema and wheezing.
• Children who are raised with pets, or who have older siblings, are less likely to develop allergies, possibly because they are exposed to more bacteria.
What can you do about it?
We’re not suggesting that you stop washing your hands or wiping your surfaces, but it might be worth a second thought before you reach for the hand sanitiser or anti-bacterial wipes, again. Perhaps there is some truth in the age old adage ‘a bit of dirt never hurt’ and maybe it’s something that we as a society need to bear in mind a little more often - as with most things, the key is about finding that happy balance.