SKEPTOID BLOG:

Nut Allergies In Schools: Epidemic or Hysteria?

With kids in the United States going back to school, parents are finding an increasing move towards "nut-free" foods in the public school system, as schools strive to eliminate peanuts and tree nuts from snacks and lunches. Many schools proudly state that they are "Nut-Free Zones," the thought being that children with nut allergies are so prevalent and allergies are so dangerous that it puts children's lives at risk. That risk is magnified at school since children without nut allergies offer their food to friends and classmates, unknowingly putting lives at risk. Some schools won't even allow foods with nuts onto school property.

A common misinterpretation is that children are developing severe and deadly allergies to nuts of all kinds, and this allergy is so prevalent that protection at all levels needs to be taken. Medically speaking, is there any truth to any of this? Is there any evidence that nut allergies are increasing in number or severity? Are blanket bans on nuts and nut products the best answer? Similar to other public school health issues this is a misunderstood area of public health. Let's take a skeptical look at the data and the precautions to parse out what is really happening.

Research has shown that reports of pediatric nut allergies between tripled between 1997 and 2008. Some of this data suffers from methodological error and reporter bias. Many of the studies were limited to patient reporting. Actually diagnosing a food allergy is somewhat subjective. It is a complicated, multi-level procedure. Many people self diagnose their food allergy. Patient history is a large part of the diagnosis but not the only part. And many people commonly think that skin tests provide the most information about allergies. This isn't really true; allergists use several tests to determine whether or not someone suffers from a sensitivity.

Diagnosing childhood food allergies is more complicated, and nut allergies do tend to appear in childhood. Parents often give histories of food allergies that are not truly food allergies. More commonly these allergies arenon-allergic food reactions, such as food intolerance. Many times food intolerance is mistakenly classified as a food allergy.

Testing is more objective; after careful physical examination and history-taking it is a large part of the diagnosis. Primary care physicians and pediatricians often undertake this daunting task, but true diagnosis typically requires a specialist. Additionally, self-reported "allergies" are commonly included in medical records without any true medical evaluation. Most physicians document food allergies on intake sheets by patient report. There is no intrinsic screening test for allergies. Sometimes parental history is the only factor that is used to diagnose the food allergy. That makes at least some of the data very unreliable. Proper diagnosis is complicated. As the organization Food Allergy and Research (FARE) describes on their website, foodallergy.org:

The first step an allergist will take to diagnose a food allergy is a thorough medical history. The allergist will ask questions to determine if food allergy may be causing your symptoms and to identify the culprit food(s), and will then perform a physical exam.

Next, the allergist may conduct tests to help identify a food allergy. While these tests alone do not always provide clear-cut answers, the allergist will combine your test results with the information given in your medical history to provide a diagnosis. These tests may include:

These tests are all proven diagnostic methods. Depending on your medical history and initial test results, you may have to take more than one test before receiving your diagnosis.

There are a host of unproven and questionable tests that are sold or used by providers. They are not recommended. FARE, in another section of their website, continues:

Unproven tests can be risky. First, they may lead to false diagnoses, with the associated anxiety and useless strict avoidance diet. Worst, they may lead truly allergic people to believe they are not allergic to certain foods, which could cause them to eat a food they are allergic to and have a life-threatening reaction.

Please note that this table only lists some of the more common tests that the National Institute of Allergies and Infectious Disease and other experts deem to be unproven and experimental. If you have a question about any test not listed here, talk to an allergist. [emphasis added]

A through evaluation by a competent provider is the best method to diagnose a true food allergy. This is expensive and time consuming. Overall, most of the epidemiology data on allergies lacks scientific objectivity. As I noted earlier, rates of food allergies in the population are heavily weighted by subjective patient reporting and the reliability of the seemingly increasing statistical rate of nut allergies is uncertain. There are several variables that give rise to sudden increase of a diagnosis. The best way to know if rates of nut allergies are actually rising is to have a simple screening test for the allergy, but that just doesn't currently exist.

For the sake of the argument let's assume that the data are 100% factual and that the numbers do show an increase in nut allergies. What does that mean?

The above graph is overly simplistic, but it approximates to a 2% increase in all food allergies. From 1997 to 2007 there was a 18% increase in all food allergies reported for children. Anaphylaxis is the life-threatening allergic reaction that everyone fears most. Anaphylactic shock occurs equally among several foods. Interestingly, although nuts do not have a higher rate or greater severity of anaphylaxis, eight foods or food groups account for 90% of serious allergic reactions in the United States: milk, eggs, fish, crustacean shellfish, wheat, soy, peanuts, and tree nuts. For children the plurality of the severe reactions occur at school, approximately 18-25% of reactions. Additionally, one out of every four allergic reactions at school are due to a previously unknown food allergy.

So why are nuts specifically the bogeyman of the school system? What makes them significantly more dangerous? I am sure that the serving of shellfish in cafeterias is at best a rare thing. Nuts are ubiquitous in foods, candies, chocolates. Are they more so than milk, eggs, or wheat? Generally the answer is no. Those are all common food ingredients.

Frankly I can find no good reason why nuts and tree nuts have become such a buggyboo in the US. Yes, there is a risk that a child with a known allergy can be exposed to the allergen at school. Additionally children may be exposed to an allergen at school that they have never come across and have a severe allergic reaction. This is inherently true for any of the above-mentioned foods.

Despite all the hysteria, anaphylactic allergic deaths in the US are relatively rare events. The average number of deaths per year, for both adults and children in the US, is about 150 for all food allergies combined. 500 people die annually from the measles. Motor vehicle deaths are the number one killer of children. The death of any child by any cause is tragic. Still, children die from choking on food at five times the rate of anaphylactic shock in the US.

In a paper for the British Medical Journal, Dr. Nicholas Christakis of Harvard Medical School proposed that increased reporting of peanut allergies, and the prevention efforts taken by schools, parents, and consumers, are suggestive of mass psychogenic illness: public hysteria far out of proportion to the level of danger.

I am forced to agree. The numbers and relative risks do not appear to be supported by enough real scientific or medical data to justify an abject ban on peanuts and tree nuts in schools. I can find no real reason why this has been given any special consideration over other allergies. Worse, this is creating an undercurrent of public hysteria that peanuts or nuts overall are bad for kids.

This anecdote is an example of how hysteria has negative consequences related to peanuts:

I have had the personal experience of parents bringing their child for an emergency evaluation of peanut exposure. The child appeared perfectly healthy on first examination. During patient history it was revealed to me the the parents brought the child in because they thought it might be the "peanut butter disease." Since I was not really sure what that meant to them I asked them to define "peanut butter disease." They proceeded to tell me that peanuts had been banned at school, they weren't sure why, but they were sure it was something wrong with the peanut butter. They wanted their child checked out to be certain that there was no poisoning or infection from the peanut butter.

You would be right to point out this is anecdote, not science. It did happen enough that the children's hospital eventually had to include a statement on the website about nut allergies and the school system.

Some proponents for nut-free zones at school would point out that taking every step to protect children is worth it. I agree superficially. In this case the steps are ineffective, or worse, misinformation. Nut-free zones do nothing to stop anaphylactic reactions of other foods. They give a false sense of security to parents about food allergies. This may result in parents failing to properly warn children who have known allergies. Children and parents may assume falsely that all other foods are OK to share with other children. It produces a public misconception about the level of danger and the prevalence of nut allergies. Some research shows that introducing peanuts at a young age lowers the risk of developing the allergy. One study show lowered risk if non-allergic pregnant women eat peanuts intra-partum. Hysteria may cause people with poor understanding of the issue to avoid nuts altogether. Nutritionally nuts, peanuts specifically are a relatively inexpensive, high-quality nutrient for low income families. And they're delicious. Banning peanuts and tree nuts generates unnecessary hysteria and possible financial stress. The bottom line is that the concern generated far outweighs the minor benefit.

The best way to deal with this is not through lunchroom or classroom restrictions. Rather, training for teachers, teachers' aides, and lunchroom workers is the key. Having staff that know how to identify an allergic reaction, where an epi-pen is located, and having available equipment is a much more effective solution. Having good information about allergies is always vitally important. Including physicians in the communications with the school system is also extremely useful and effective. These measures can provide some real protection. Plus, they encourage parents to actually go forward with the proper testing to determine the actual allergy issue involved, rather than the supposed one.

In my opinion banning nuts is a hysterical measure that feels good while offering little real prevention of severe allergic reactions. It helps somewhat with one small section of a tiny population at risk. It is a cheap and less helpful solution than staff awareness, training, and epi-pens.

I also find it acutely ironic that schools will let an unvaccinated children go to school, yet feel that a peanut butter sandwich in a lunch box is an unacceptable risk. Realistically what is more dangerous for the kids?

Bring it up at PTO and school meetings, ask good questions, be skeptical when it comes to a non-descriptive solve all solution for school age children problems. Chances are those solutions sound good but fail with scrutiny. Most solutions that work require individualized plans, not blanket rules. Bureaucracies love rules and hate individual plans because generalized rules often work best for the bureaucracy. That doesn't mean it works the best.