The prevalence of peanut and nut allergies are hard to know precisely. Getting reliable stats can be tricky because sometimes people think they have a food allergy when they don’t (they may have a ‘food intolerance’). Other times people may not realise that they have a food allergy because symptoms are missed or ignored. However, in the UK, 1 in 70 (1.4%) people are thought to have nut or peanut allergies. The rates of peanut and nut allergies seem to be on the rise (no one knows why) and have tripled in the space of a decade. In the USA, the CDC reports 3.9% of under 18’s have a food allergy (not just peanuts).
Nut and peanut allergies can cause gut or bowel problems but it is more common to have symptoms such as itching, flushing, hives, as well as swelling around the mouth. Only 4% of peanut or nut allergy sufferers have digestive symptoms such as cramping and diarrhoea.
In the severest cases, anaphylaxis occurs – a life threatening reaction that can cause the throat and tongue to swell and for wheezing and shortness of breath. There can be a massive and sudden decrease in blood pressure and death is a very real possibility. Anaphylaxis is always a medical emergency needing a prompt injection of adrenaline (e.g. from an ‘EpiPen’).
In a personal aside, a friend of mine (who is now in her late 40’s) has a peanut allergy. While in Paris about 10 years ago she was accidentally exposed to peanut oil and ended up needing to be medi-vaced to a military hospital, as it was the closest place with adrenaline. She’s still alive and well but I now know that anaphylaxis can be really, really scary.
More hopefully, a successful early trial of a treatment for nut allergy was recently reported. Starting with carefully measured, tiny doses of peanut flour and gradually increasing them, allergic children can be made tolerant to the peanuts.
Answer by Lewis Pike and Dr Stu
Question from Rob Langone
Read more: Food allergies (NHS Choices)
Image source: EuroMagic, on Flickr