It’s an allergy season again. If you’re one of the 81 million Americans who suffer from hay fever, spring is both a blessing and a curse. Yes, the days are longer, but they are accompanied by itchy eyes, runny nose, and the endless search for antihistamines. On days when the pollen count is higher, seasonal allergies are like an attack—from the outside world, but also from our bodies’ heightened immune systems.
There are increasing numbers of allergy sufferers, too. In 1997, about 0.4 percent of American children were reported to be allergic to peanuts. By 2008 the figure was 1.4 percent. In the United Kingdom, hospitalizations due to severe food allergies tripled between 1998 and 2018. Although rates of asthma — often caused by allergies — have leveled off in the United States, they continue to rise globally thanks to increasing rates in developing world. We’re also seeing a rise in unusual allergies, such as alpha-gal syndrome, where some people who have been bitten by lone star ticks develop strong reactions to red meat.
Given the heightened sensitivity, it is hard to shake the feeling that something is out of control. Either it’s the outside world, our bodies, or the complex interplay between the two, but something is going wrong. The question is why – and what can we do about it?
A good place to start is to find out what the hell allergy actually is. in her book Allergies: How our immune system reacts to a changing world, medical anthropologist Teresa MacPhail is trying to do just that. One theory is that allergic reactions evolved as the body’s way of flushing out carcinogens and toxins — from insect stings to snake bites. Even a few centuries ago, a severe immune response to a deadly snake bite might have been a beneficial way for the body to respond, one researcher told MacPhail.
As the world changes, our overactive immune systems begin to seem decidedly out of touch with the threats we face. It doesn’t help that the cropping seasons are longer, exposing people to pollen early each spring. At the same time, changing diets and lifestyles are throwing our microbiomes out of whack and possibly making children more susceptible to food allergens. Stress may also affect our susceptibility to allergies – we know that stress hormones trigger a kind of response in mice’s cells like allergens.
If that sounds a bit indecisive, you’re right. As MacPhail discovered, it’s hard to say exactly why allergies are on the rise—doctors don’t even fully agree on what an allergy is He is Or how best to diagnose one. But MacPhail has good reason to dive into the intricacies. In August 1996, her father was hitchhiking down New Hampshire on his way to the beach with his girlfriend. A solitary bee flew through the open car window and stung him on the side of his neck. Soon after, her father passed away from anaphylactic shock. He was 47. “You’re really here today because you want to know why your father died,” an allergist told MacPhail during an interview.