According to the Merck Manual:

Food allergy is an exaggerated immune response to dietary proteins.

Food allergy should be distinguished from nonimmune reactions to food (eg, lactose intolerance, irritable bowel syndrome, infectious gastroenteritis) and reactions to additives (eg, monosodium glutamate, metabisulfite, tartrazine) or food contaminants (eg, latex dust in food handled by workers wearing latex gloves), which cause most food reactions. Prevalence of true food allergy ranges from < 1 to 3% and varies by geography and method of ascertainment; patients tend to confuse intolerance with allergy.

Food allergies are usually diagnosed by a skin test, RAST, or an elimination diet. It is important to diagnose food allergies, because they have the potential to cause fatal reactions. Food allergies tend to be self-evident, because once the substance is ingested, or even inhaled by the sensitive individual, an anaphylactic reaction of swelling, hives, and breathing problems can occur. Most people with severe food allergies, such as peanuts, need to carry an epi-pen (or purification essential oil if you so choose) in case they are exposed to their trigger.

Food sensitivities are defined as the inability to properly digest or assimilate food. They are a relatively new paradigm in medicine and evidence is still being compiled about their correlation to disease processes. Serum labs, such as ALCAT and cytotoxicity, have been used to diagnose sensitivities. Many holistic providers also use muscle checking and/or elimination challenges with these tests.

I am strong believer in the “you are what you eat/absorb” theory so this makes sense. Due to the fact that our food supply is continually being more tainted with chemicals, toxins, and additives, I can understand why this issue of improper digestion is becoming more common. Clinically, I have seen many vague symptoms, such as headaches, muscle and joint problems, digestive disturbances, and skin problems, virtually disappear when patients comply with an elimination diet of the most common food sensitivities. Invariably, when they add the triggering food back into their diet, they once again experience the symptom, and it is sometimes a more extreme response.

“Dr. Sarah, why is it more noticeable now?” they ask me. My belief is that the body has just gotten cleaned out and so it can now communicate more effectively when it is overpowered by offending agents. When the body is weak due to a heavy build-up of a variety of chemicals that it can’t absorb, its response to them will also be weak. However, when the body is rebuilding and increasing in vitality, it is able to respond more powerfully and effectively about what is bothering it.

As my clients can attest to, I like to suggest blood tests from their PCP in order to obtain an objective measure and baseline value. I also implement other tools including integrative lab work for each individual which helps assess their specific food triggers. I rely on a combination of clinical symptoms, the elimination challenge, blood tests such as ALCAT, and my background in Applied Kinesiology.  This is because I believe in unifying science with intuition and the body’s innate healing potential. For this reason, I believe it’s important to have an integrative, broad viewpoint on diet.

Three important Side Notes:

1. In his new book, The Genotype Diet, Dr. Peter D’Adamo explains how certain foods can cause different reactions in different people due to genetic predispositions and environmental cues. According to Dr. D’Adamo, one person’s fountain of youth could be another’s poison. He explains this through epigenetic factors and dietary influences such as methylators and acetylators of DNA. This book provides cutting edge science on how we can literally modify our genetic expression by what we put in our mouth. If food can do this, not absorbing it correctly can certainly attribute to a wide array of symptoms.

2. It is important to note that your digestive tract contains half of your immune system response and contains more serotonin receptors than in your brain. This is why you feel so tired and sad after a sugar high and why you lash out in anger when your blood sugar is low. It is also why people with chronic yeast infections or Candida have such poor health and mood imbalances with their mal-absorption symptoms.

3. Due tot the fact that I am a Naturopathic Doctor, I want to get to the cause of the food sensitivity. I usually find the problem is usually due to poor gut permeability or leaky gut syndrome. I have found that once the gut is cleaned up and the barrier is restored, many people can once again enjoy the foods they are sensitive to on a moderate basis. This is a good thing, because most people don’t like life sentences of avoidance!