Natasha Salmon suffers from food allergies, she cannot be in close proximity to a bowl of peanuts without struggling to breathe. Natasha’s allergies first developed when she was five, and they are developing as she grows older – the 21-year-old student from Surrey became allergic to raw fruit and vegetables as well as nuts when she turned 15 and says her allergies are getting worse.
“There is no doubt that my allergies are getting worse. My immunologist can’t explain why, though it’s thought to be related to my hay fever. I just have to deal with them and hope they subside.”
Food allergies like Natasha’s have risen over the last 20 years, with 1-2% of adults and 4-6% of children now thought to be affected. So, why the rise in allergies? A recent theory has been published in the Annals of Allergy, Asthma and Immunology suggesting that certain chemicals called dichlorophenols may be to blame. Researchers in the US looked at food allergies in over 2,000 people and discovered that those with high levels of dichlorophenols in their urine had an 80% higher risk of having an allergy.
The theory suggests that these chemicals (which may be found in purified tap water, disinfectants and pesticides) have anti-bacterial properties that could potentially affect the microflora in the gut which are said to protect us against food allergies.
So, is it time to ditch the tap water and only drink bottled? Jonathon Brostoff, professor of allergy and environmental health at Kings College London doesn’t think so. He believes that the study is flawed for several reasons, for one, food allergy diagnosis is complicated and testing by blood tests alone is only 50% reliable.
“Another problem is that the study didn’t publish its results on how many people with the lowest levels of dichlorophenols tested positive for food allergy,” he adds. “It might be possible that these chemicals affect the balance of the immune function and the risk of food allergy, but we would need far more data to show cause and effect.”
Even if a link between the two was discovered, UK water is very safe according to Professor Jeni Colbourne (head of UK’s Drinking Water Inspectorate).
“In the UK there are strict controls requiring water companies to monitor water for the presence of phenols and to minimise the presence of such disinfectant by-products,” she says. “Water tastes foul when dichlorophenols are present, even at exceptionally low concentrations, so taste and odour monitoring is the other safeguard. Even if present in trace amounts in tap water, consumers would be reporting it in very large numbers.”
If you are struggling with food allergies, a nutritionist could help you. To find out more, take a look at our Food Allergy and Food Intolerance page.
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