Allergy rates are growing in the UK and women are more likely to report suffering from an allergy than men. Why are we most at risk and what is that we’re reacting to?
Due to the recent tragic case of Natasha Ednan-Laperouse who died due to eating a unlabelled Pret a Manger baguette that contained sesame, the prevalence and severity of allergies has been headline news and highlighted in public consciousness more than ever before. Pret a Manger has since announced that it will be listing all ingredients (particularly highlighting 14 common allergens ) on products sold while campaigners and MPs are urging environment secretary Michael Gove to change food safety regulations to make it a legal requirement for large food retailers in particular to display clear allergan information on individual products.
It’s a change that’s desperately required in the UK especially given that we have the highest prevalence of allergic conditions in the world according to Allergy UK , with 20 per cent of the population affected by one or more allergic disorders. The same proportion of people report experiencing a hypersensitivity to certain foods, while in the 20 years to 2012 there was a 615 per cent increase in the rate of hospital admissions for anaphylaxis in the UK. It seems that allergy cases are snowballing and women are one of the most vulnerable groups, with a reported allergy rate of around 50 per cent. What’s causing our immune systems to increasingly react to substances that might normally be harmless and why are women bearing the brunt of the allergy epidemic?
The truth is that the experts are currently as boggled as we are, as research published in The Journal of Allergy and Clinical Immunology last year indicates. The study involved assessing 2.7 million adults and children between 2000-2013 in the US and concluded that women were more likely than men to suffer from food allergies, with the most common allergies being shellfish, fruit and vegetables and dairy. Interestingly, men were more prone to peanut allergies than women, but otherwise a health facility reported that women had it worse and researchers were at a loss as to why. Of 100,000 participants who were found to suffer from a food allergy, the most common symptoms were rashes, vomiting and coughing, while 16 per cent experienced life-threatening anaphylactic reactions.
This most serious form of allergic reaction was also shown to be more common among women in a 2014 study published by the US National Institute of Allergy and Infectious Diseases, with researchers this time linking the anaphylaxis imbalance between genders to the female hormone oestrogen . Experiments showed that female mice experienced more severe and prolonged anaphylactic reactions than males due to the effect of the oestrogen hormone oestradiol on blood vessels. Oestradiol enhanced the activity of an enzyme in the lining of vessels that increased the production of nitric oxide, triggering swelling and a drop in blood pressure leading to anaphylactic symptoms. When this enzyme was blocked by researchers, however, there were no differences in reactions between male and female mice.
While more research is required, scientists have hypothesized that it’s this hormonal interaction that could explain why more women than men are admitted to hospital for severe allergic and anaphylactic reactions. Oscillating oestrogen levels could also account for why women become more susceptible to allergic conditions post-puberty - pre-adolescence, boys are actually more likely to suffer allergies than girls, but this reverses in the teenage years. Similarly, endocrinologists have linked fluctuating hormones to the rise in allergies among women in mid-life, as rollercoastering oestrogen during the perimenopause and menopause could contribute to the increase in asthma, eczema , hayfever and food allergies reported in women of this age group, even if they hadn’t suffered with any hypersensitivity previously.
It could simply be that women are more diligent about documenting and seeking help for allergies, or that men have different types of antibodies that inhibit reactions, and until we have wider research and evidence to draw on we won’t know for sure, but the hormonal clue seems too prevalent to ignore. Oestrogen yo-yos could also clarify why some women experience more severe reactions at different times during their menstrual cycle and why allergies appear to worsen during adolescence, pregnancy or around childbirth.
Theoretically everything from hormonal birth control to HRT during the menopause could help to redress the gender allergy gap, but as with many aspects of women’s health , more investment in research is key, particularly seeing as Allergy UK predicts that 30 million of us could be suffering with allergic conditions by 2030, with allergy onset in later life among women a key area of concern. Until then, greater awareness and information around allergies is essential, on a political level and just if you have friends coming round for dinner. No one knows for sure why allergies are increasing globally and everything from our more sterile environments to an over reliance on antibiotics and a lack of diversity in Western diets have been blamed for impairing our immune systems and making allergies more widespread, but improving quality of life and outlook for sufferers is something we can all contribute to until researchers crack the allergy code.
For more information, resources and support relating to allergy and allergic reactions visit the Allergy UK website