Tales of people developing allergies to red meat have been making the rounds lately. I feel bad for others afflicted with the ailment, but I’m happy to know I'm not a freak.
I've had a confirmed allergy to red meat for more than three years now, but it's only recently that I've come to understand what’s happening.
An Allergy to Taxes?
My story begins when I was sitting in the tax office in 2013. I noticed I was getting itchy and feeling really hot, so I went to the bathroom and splashed some water on my face. I saw in the mirror that I was pretty red, but I was determined to finish my business. A few minutes later, when I was with a tax processor, it became difficult to breathe and I could feel my face swelling.
He must have noticed, too. He resolved my issues and had me out of there in less than five minutes—maybe he didn't want me to die in his office!
I knew I was in rough shape, but I did my best to keep my cool and take the fastest route to a nearby urgent care clinic. I tried to fill out the paperwork, but the nurses realized I was in a bad way and got an IV full of Benadryl in my arm within minutes. Apparently, when people think you're dying, they give you speedy service!
A few hours later, I awoke from a deep, medically induced nap and had a prescription for an Epi-pen. But I had no idea what caused the attack.
I went to an allergist and we discussed all the things I had eaten that day, a childhood bee sting, and my love of spicy foods, but we really didn't have any clue about what had happened to me.
Fortunately I was back on my feet pretty quickly. But every few months or so, I would find myself waking up in the middle of the night with labored breathing and a strange rash at the base of my hairline and on my arms and legs.
I'd typically apply some anti-itch cream or take some Benadryl and sleep it off, feeling fine the next day. But I just couldn't match cause with effect.
Finally, a pattern emerged.
Once, on a road trip, my friends and I found ourselves in a small town that was having a rib fest. I'm a pretty socially conscious person, so I try not to eat too much red meat in my daily life, because not eating meat is a great way to reduce your carbon footprint.
But I have a weakness when it comes to ribs. I joyfully ate a full rack of ribs that night, but I spent the rest of my trip under the influence of Benadryl and smothered in anti-itch cream.
Later it hit me: I'd had these same symptoms after grilling ribs at home, after eating a very beefy stew with a Boy Scout troop I worked with, and after a moment of weakness with a fast food cheeseburger.
So I made an appointment with my allergist to have her test me for allergies to red meat. At first she scoffed at the idea but essentially said she'd take my money. About a week later, she was eating her words and told me I should stop eating red meat. But she couldn't really identify why.
I'd browsed the internet and heard of others with similar allergies, but it wasn't until I listened to a RadioLab podcast that I really came to understand what has happened to my body. I have developed an allergy to alpha-gal, a sugar molecule found in mammal meats.
It’s likely that several years earlier I was bitten by a lone star tick, a species that lives across most of the eastern half of the United States and is named for the Texas-shaped white spot on its back.
As Wired magazine describes it, "Something in the tick’s saliva hijacks humans’ immune systems, red-flagging alpha-gal, and triggering the massive release of histamines whenever red meat is consumed."
A cancer drug trial helped scientists learn about the illness.
Some of the nation's foremost researchers at the Asthma and Allergic Disease Center at the University of Virginia have been looking into the alpha-gal story.
Their work began when two pharmaceutical companies were developing a drug to help treat colon cancer. The drug makers noticed that some recipients of the treatment—mostly in the southeastern United States—had harsh allergic reactions to the experimental medicine.
The UVA scientists determined that the people experiencing ill effects were having a specific allergic reaction to alpha-gal carbohydrates found in the medicine.
Clever epidemiologists on the team noticed that when they made a map of where these allergic reactions occurred, it looked almost identical to one showing outbreaks of Rocky Mountain spotted fever—another disease carried by the lone star tick.
"At this time," wrote the researchers "three members of our group developed red meat allergy and each one distinctly remembered being bitten by ticks weeks or months prior to the development of symptoms."
Using before-and-after blood samples, the researchers found that after getting bitten, the participants’ antibodies that react to alpha-gal "had increased dramatically (4 to 10-fold)."
"Following up on this connection," the UVA researchers wrote, "we started to ask patients about tick bites and rapidly became aware that most of those with delayed anaphylaxis had experienced recent bites from adult or larval ticks."
The scientists were excited to recognize what was causing these allergic reactions to both the cancer drug and mammal meat, but they still couldn't identify the exact mechanism.
Three dominant theories are:
1) There's something in the tick saliva that mimics alpha-gal and causes our bodies to "label" that carbohydrate a bad thing that should be attacked.
2) The ticks pick up alpha-gal chemicals when they suck on other mammals' blood and then transmit it to humans when they bite us.
3) The ticks are carrying another organism, perhaps a bacteria, that is causing the reaction.
The researchers note that "it remains a striking challenge to identify why the response is so strong and why it is directed so consistently against the alpha-gal carbohydrate residue."
Living With a New Allergy
While scientists work out what to do about it, I try to remind myself that this disease has helped me make an ethical lifestyle choice—eating less mammal meat. But it’s not always easy. It turns out that even something as simple as broth can set off a reaction!
The first thing that caused me trouble that day at the tax office was a favorite dish, authentic Chinese hand-pulled noodles in beef broth. It kills me that I can't have them again.
I traveled to Savannah, Georgia, last winter and went to a restaurant famous for their seafood boil. My partner and I made sure to ask for our meal without any red meat, but the restaurant’s kitchen is essentially just a giant vat of steaming shrimp, crawfish, corn, potatoes—and sausage.
A few hours after the mouthwatering seaside meal, I felt my palms itching and that familiar rash starting at the base of my hairline. I reluctantly popped a Benadryl, knowing it would knock me out for about 12 hours of my vacation.
When I awoke the next morning, I learned I had slept through a breathtaking display of dolphins splashing around just a few feet off the beach where we were. Grrrrrr…lone star!
This doesn't have to happen to you.
Ticks hang out in the woods, in shrubs, and in weeds and tall grasses. Check yourself regularly whenever you're in these areas in warmer months.
I'm not suggesting that you don't go outside, but make sure that you take precautions when you head into nature.
There are several strategies for avoiding tick bites when you’re outdoors: Tuck your pants in your socks, apply bug spray that has DEET as the active ingredient, and wear light-colored clothing so you can tell when ticks are crawling on you. You can even buy clothes that are treated with a tick-murdering chemical called permethrin.
These strategies should help keep you safe (unless you want to miss out on eating ribs and seeing dolphins, of course). And as always when it comes to health concerns, get in touch with a healthcare professional if you think you may have encountered the lone star tick.