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When parents think of food allergies affecting their children, peanut allergies are often the number one contender. It’s when a child inadvertently eats a peanut-containing or peanut-contaminated food and has an allergic reaction—sometimes within minutes or sometimes much more slowly, as with an allergy contributing to ADHD.

Those reactions can range from distressing, like a runny nose, to the disastrous and deadly, like anaphylactic shock.

But whether the symptoms of food allergy are just annoying or actually life-threatening, the physiological basics of the reaction are the same. The immune system mistakenly identifies a protein in peanuts as a foreign invader.

It then creates an “antibody” to alert invader-slaying cells about the substance—in this case, the antibody is called “immunoglobulin E” (IgE). As the antibody does its job, it triggers the release of “histamine.” This chemical expands capillaries, the tiniest of blood vessels, triggering a runny nose and eyes, redness, itching, swelling and the like.

Intriguingly, children with ADHD have a much higher rate of IgE allergies than children without the disorder—in fact, one study shows they are seven times more likely to have IgE-caused food allergies, including dairy allergies, than non-ADHD children.1

They are also more likely to have ear infections, eczema, and asthma, all of which are linked to allergies. I see it this way, as it fights allergens, the active immune system creates inflammation.

For children with ADHD, the brain also gets inflamed as a byproduct. But there’s another brain-inflaming allergy most parents are unaware of.

Immunoglobulin G allergies and ADHD

There’s a second kind of food allergy that’s far less known — and it can be just as troublesome to a child. Particularly an ADHD child who is 6 or younger, when the immune system is at its most vulnerable.

These food allergies aren’t mediated by IgE. Instead, they’re mediated by another antigen: “immunoglobulin G” (IgG).

These allergies don’t kick in merely minutes after your child eats. They usually happen hours afterwards—or even two to three days! I call this type of allergic reaction “delayed hypersensitivity.”

Doris Rapp, MD was a pediatric allergist and author of the national bestseller Is This Your Child?—Discovering and Treating Unrecognized Allergies in Children and Adults.

In her book, Dr. Rapp writes, “Many traditional allergy specialists believe that allergies can only affect limited and specific parts of the body. The nose, eyes, lungs, skin and intestines are accepted areas. They would not believe that the brain functions of children could be influenced by a food.”2

And in her chapter on hyperactivity, she writes “Some of these children merely have undetected allergies affecting their brain.”

Allergies, she continues, can produce the following symptoms, among many others:

  • Hyperactive, uncontrollably wild, unrestrained
  • Nonstop talk, repetition, loud talk, stuttering
  • Inattentive, disruptive, impulsive
  • Short attention span, unable to concentrate
  • Nervous, irritable, upset, short-tempered, moody
  • High-strung, excitable, agitated

Another specialist, Marshall Mandell, MD, systematically tested ADHD children with oral drops of hundreds of different food proteins. Before and after the drops, he tested the children for handwriting legibility and math ability.

I have a vivid memory of one ADHD child who received a drop of peanut antigen: his handwriting went from readable to unreadable, and he was no longer able to solve the type of math problems he’d been solving easily just an hour before.

Remember, neither the mother nor her child knew which drop was which: the child received many drops, and only peanut caused the behavioral problems. Needless to say, the mother stopped feeding her son daily peanut butter-and-jelly sandwiches with “healthy” whole wheat bread!

How to Detect an Immunoglobulin G (IgG) Allergy

In my practice, IgG food allergy is the main (and sometimes the only) problem I need to detect and correct in about 25% of ADHD children under 12 and about 75% of ADHD children under 6.

But how can you tell if your ADHD child has an IgG food allergy? There are two main ways.

  • At-home pulse test—An IgG food allergy can cause the heart to race, sometimes up to 20 or 30 beats per minute above normal. If you suspect a food is an allergen, check your child’s pulse before he eats and again one to two hours later. If his pulse is racing, consider eliminating the food from his diet.
  • Doctor-ordered blood test—The “IgG Food Allergy Test,” available from Great Plains and many other labs, tests nearly 100 foods. I give this test—a finger prick blood test—to every one of my ADHD patients under 12. I also give it to adolescents and adults I suspect might have an IgG food allergy: those who have an IgE allergy to pollen or other substances; a family history of allergies; or an allergy-related disease like asthma or eczema.

The IgG Food Allergy Test rates the IgG response from 1 to 5, with 1 the weakest and 5 the strongest. If the test score is 3.5 or higher, I recommend parents do their best to eliminate the food from the child’s diet.

Dairy is by far the most common food allergen, followed by wheat, corn and eggs.

The current IgG Food Allergy Test is very accurate. With newer, more sophisticated and more accurate testing, it has become relatively easy to detect which foods are the culprits causing allergies.

For some children, eliminating the offending food(s) can completely resolve ADHD allergies. For others, this is part of a multi-factor approach—because there are multiple factors to take into account.

There is never a one-size-fits-all approach for finding allergies to reduce ADHD.

However your child responds, once the food (or foods) have been eliminated, her immune system will start to calm down. You can usually reintroduce the food after one to three years, if your child eats the offending food no more than once every three to four days. More frequent intake tends to retrigger an IgG food allergy, so it’s something to keep an eye on.

I discuss food allergies, as well as a wide variety of natural and medicinal methods to help children suffering from ADHD in my award-winning book, Finally Focused.

Yours in health,

James M. Greenblatt, MD
Founder, Medical Director, Psychiatry Redefined