25 facts about food allergies

Food allergies are very common. According to the organization Food Allergy and Research Education (FARE), 32 million Americans have food allergies. That’s about one in 10 adults. The figure also includes 5.6 million children, which is approximately two kids in every classroom. Also according to FARE, almost half (40%) of children with food allergies have more than one food allergy.

There are more than 170 foods that have been reported to cause an allergic reaction. But eight specific types of food are responsible for more than 90% of them. The "big eight" are milk, eggs, peanuts, tree nuts, wheat, soy, fish, and shellfish. The Food and Drug Administration requires all food product labels to have the food source name of any ingredients that are these allergens. They also require labels to tell you if they contain any protein that is derived from one of these major allergens.

It’s been estimated that 150 to 200 fatalities a year in the U.S. are due to food allergies. However, this statistic has been challenged by Forbes and the New York Times, among others. In 2019, the National Food Allergy Death Registry recorded just eight fatalities from food allergies. Further, a 2017 study reported that death due to food allergy was between 0.03 and 0.3 deaths per million people.

It’s possible to outgrow allergies but it depends on what kind of allergy and how severe it is. Research has shown that 60% to 80% of children who have a milk or egg allergy will be able to eat those foods by the time they’re 16 years old, but only 20% of kids with a peanut allergy will outgrow it. Evidence also suggests that tree nut allergies and fish or shellfish allergies are even harder to outgrow, with only 14% and 4% to 5% respectively, of people being able to eat those later in life.

One day you might not need to ask if the baked good was made in a peanut-free environment. Smart kitchenware, such as plate or cutlery, could warn people with allergies if there are problem ingredients.

Back in 2011, industrial designer Hannes Harms, created a prototype system that uses edible radio-frequency ID (RFID) tags to track food from production to your plate. The smart plate that comes with the system can then read the RFID tags and tell you exactly what's in your dinner. In 2016, a Canadian teen made smart cutlery that detects allergens, nutrients, and toxins. The product is apparently still in the research and development phase but the spoon, fork, and chopstick could be a meal changer.

Between 1997 and 2011 food allergies in children have increased from 3.4% to 5.1%, according to data from the Centers for Disease Control and Prevention. One theory behind the rise in food allergies is the “hygiene hypothesis”, which suggests that the environments that kids are growing up in are too sterile and they aren’t being exposed to enough germs to train their immune system on what’s good or bad. Other research has pointed to increased use of antibiotics and vitamin D deficiency. But so far there’s no clear answer as to why rates are increasing.

Food allergies can be serious and life threatening. According to FARE, every three minutes someone ends up in the emergency room because of a food allergy and each year 200,000 people need emergency medical care for an allergic reaction to food. They also note that child hospitalizations for food allergies as well as treatment for anaphylaxis related to food allergies has increased dramatically in recent years.

While not actually a food allergy, people with this syndrome develop symptoms of an allergic reaction, such as itchy mouth, scratchy throat, swelling of the lips, after eating raw fruits, vegetables and sometimes tree nuts.

The syndrome is also referred to as pollen-food allergy syndrome and happens when the immune system is triggered by pollen and similar proteins in the food. People who have this type of allergy usually don’t react if the fruit or vegetable is cooked because heat changes the proteins the immune system usually reacts to.

Food allergies cost U.S. families a lot of money. Researchers reporting in the Journal of the American Medical Association to be $4,184 per child annually (around $25 billion). Roughly $4.3 billion, or $724 per child, of that amount relates to direct medical costs and out-of-pocket costs for families was $5.5 billion with about a third of that being for special food.

One 2017 study in the Journal of Pediatrics found children with a food allergy were more likely to have anxiety. The study looked at more than 80 children between the ages of four and 12. The researchers found that those with food allergies had more symptoms of social anxiety and higher levels of anxiety in general.

Allergies in general have also been linked to mood disorders such as depression and anxiety.

After being bitten by the lone star tick people have reported allergies to red meat such as pork and beef. Sometimes the allergy can be especially severe and people can react to any animal by-products including wool, soaps, vaccines, and more.

It’s called alpha-gal allergy, and it’s totally thrown a wrench into how scientists thought allergies occur and how they’re triggered. For example, one huge difference with this allergy is that alpha-gal is a sugar, not a protein. Also reactions take hours to occur, while most food allergies happen within minutes of exposure.

If having a food allergy wasn’t bad enough, it turns out a third of children are bullied for it. A 2014 study from The Journal of Allergy and Clinical Immunology: In Practice found that 32% of children with food allergies had been bullied at least once, and about a third of the kids who were bullied more than twice a month.

Television and movies may have given us some skewed ideas of what an allergic reaction looks like. Symptoms of a food allergy appear within a few minutes to two hours after a person has consumed the food they’re allergic to. The most common food-allergy symptoms are tingling or itching in the mouth, hives/itching, swelling of the lips, face, tongue, and throat, but it can also happen to other parts of the body. Symptoms can also manifest in trouble breathing, abdominal pain, nausea or vomiting, diarrhea. A person might also get dizzy or faint.

There are three things needed to sustain life: oxygen, food, and water. That’s why aquagenic urticaria, or an allergy to water, is so awful. While it is very rare and is usually only triggered by things like showers, pools, or rain, people who have the disease often have to watch what they eat and drink. They might avoid fruits and vegetables with high water content or switch to soda instead of drinks that are mostly water-based.

Adult allergies are way less common than childhood allergies. Just over 10% of adults have a food allergy, according to a l arge study done in 2019. Also interesting, is that only 15% of people with food allergies are first diagnosed in adulthood, according to FARE. The most common allergy in adults is shellfish.

In 2012, a doctor infected himself with hookworms and claimed they had positive effects on his health. He said they could cure or at least help alleviate the symptoms of food allergies, inflammatory bowel disease, and asthma. The worms apparently suppress the immune system. But don’t believe the hype: When actual scientific studies were conducted, results were not positive at all.

Manipulating the gut microbiome could maybe help treat food allergies. A 2004 study published in the The Journal of Immunology found that if you got rid of their gut bacteria in mice they had allergic responses to peanuts. Researchers have continued to look into how the gut microbiome can impact allergic reactions. There’s been some mixed results with things like using probiotics, but there’s been some promising animal study results with fecal transplants. 

African American children are at a bigger risk of developing a food allergy than white children. A 2016 study published in the Journal of Allergy and CLinical Immunology found that of 817 children, African American children were more likely to have allergies to wheat, soy, corn, fish, and shellfish than other races. Hispanic children were the least likely to develop a food allergy, according to data from the National Health Interview Survey.

If you’re allergic to latex you might also be allergic to some foods, specifically fruit. It’s called latex-fruit syndrome and it happens because of something called cross-reaction. The body is sensitive to certain proteins in latex and some of these proteins are found in fruit like bananas, kiwis, peaches, and more. People who have this syndrome can also react to vegetables, grains, and some nuts.

Data from the National Health Interview Survey, conducted between 1997 and 2011, revealed that higher income levels were associated with a higher prevalence of allergies. It found that kids whose family had an income of more than 200% of the poverty level had a food allergy prevalence of 5.4%. This is compared to lower levels of income where the rate was less than 5%.

The number of people with food allergies might be overestimated. That finding comes from a 2019 study published in JAMA Network Open and led by Dr. Ruchi Gupta, MD, MPH, from Ann & Robert H. Lurie Children's Hospital of Chicago and Northwestern University. Gupta's research looked at more than 400,000 people across the U.S. and found that one in 10 adults actually have a food allergy, but almost 20% reported they were allergic to certain foods even if they didn’t have the allergic reaction symptoms to back it up.

Many adults seem to be confusing food intolerance with allergic reactions, according to the researchers. A food-intolerance reaction is usually limited to digestive issues and is quite mild in comparison to an allergic reaction, which involves an immune system response that affects multiple systems.

One company in Japan came up with possibly the coolest allergy test ever. Dermatologist Mami Nomura and ad agency J. Walter Thompson came up with a temporary tattoo, which when applied properly can turn red if the person is allergic to buckwheat. Buckwheat, while not super popular in the U.S., is very common in Japan, especially in soba noodles. For the tattoos, much like a skin prick test used to test for allergies in a clinical setting, the user needs to prick their skin, then they apply the tattoo using a soba noodle broth. If you’re allergic to buckwheat then the red irritated skin will show in the clear part of the tattoo.

There is currently no cure for food allergies, just tools for management. The best method is avoidance but depending on severity the use of antihistamines or an epinephrine autoinjector (EpiPen) can deal with unexpected run-ins. There’s also been limited success for some people to use immunotherapy, also called allergy shots, to train the body to become less allergic to things. Patients are exposed to low, increasing doses of an allergen over a period of time.

[Pictured: An allergy and immunization technician injects a patient with an immunotherapy allergen during their visit with the immunization clinic.]

It’s a myth that if you delay introducing allergenic foods, like peanuts, to your children you can protect them from getting the food allergy. In fact, research has shown that giving small doses of the allergenic food can help reduce the risk of them developing the allergy. The American Academy of Allergy, Asthma and Immunology recommends adding egg, peanuts, fish etc. into a baby’s diet between the ages of four and six months. They also say moms shouldn’t remove any allergens from their diet while breastfeeding.

While allergies are by no means contagious, it is possible to contract one. A case study published in 2018 by the Department of Medicine at University of California-San Diego found that one woman developed a peanut allergy after receiving a lung transplant from a donor with a peanut allergy. The case was extremely rare: The doctor who treated the woman told LiveScience that there have only been four or five reported cases of this ever happening.