Food Allergy/Toxicity

Overview Definition

A classic food allergy occurs when the body's immune system responds to otherwise benign proteins (allergens) as though they threatened the health and integrity of the system. In a classic reaction, the immune system attempts to counter the food allergens by stimulating IgE and IgG antibodies. When these antibodies react with the allergen, histamine and other chemicals (mediators) are released.

Type 1 Reactions

You know when you have one because your body suffers a notable and almost instant reaction such as itching, swelling, hives, and breathing difficulties. While most food allergies are mild, in some cases, they can cause anaphylactic shock. Because this type of reaction can be life threatening, this type of food allergy must be taken seriously. Approximately 5% of children younger than age 3 have Type 1 food allergies. According to the National Institute of Allergy and Infectious diseases, fewer than 2%—about 4 million Americans—have Type 1 food allergies.

Type 2 Reactions

The majority of food allergy reactions are Type 2 reactions. These are not immediate, making them almost impossible to detect without sophisticated testing. Different foods break down at different rates, causing symptoms anywhere from 24-72 hours after ingestion, depending on the food and your unique body chemistry. Because of the delay in onset of symptoms it is often difficult to associate the use of food with reactive symptoms. Unfortunately, the foods that cause this toxic shock vary widely according to your individual susceptibility. Perfectly healthy foods can cause a variety of symptoms that can affect any organ system in your body. This type of reaction is far more common than many people believe. Many allergists believe that only a few people have food allergies. A 23 year ongoing study reveals that 95% of the population has this Type 2 toxic reaction to common everyday foods that you eat regularly.

Food Intolerance/Hypersensitivity

Another source of adverse reactions to food are caused by nonimmulogic mediated mechanisms. Also called food intolerance or food hypersensitivity, adverse food reactions can occur because a person lacks the enzymes needed for proper digestion, such as for the lactose in milk, or has a sensitivity to such common preservatives, colorings and additives such as monosodium glutamate (MSG), sulfites, and gluten. Some adverse reactions are caused by food-borne microbial pathogens and toxins.

Signs and Symptoms

Clinically, the digestive system, the immune system, the cardiovascular system and the nervous system are the most frequently affected. Common clinical dysfunctions include cramps, constipation, diarrhea, hemorrhoids, Crohn's disease, colitis, congestion, inflammation, fatigue, hyperactivity, anxiety and depression. The weakest link in an individual's system is often the first to show a sign of dysfunction.

Diagnosis

Physical Examination

Physical assessment includes noting characteristic symptoms, signs, and pattern of reaction, as well as a history of past exposures and reactions to related foods.

Laboratory Tests

There are several tests that help in the diagnosis of food reactivity. They all have there advantages and disadvantages. Unfortunately, there is no one simple, !00% reliable, inexpensive test available for food sensitivity testing. This is because no one test can measure all types of food reactions mentioned above. What we look for is a test that can give the most reliable information, which if followed, will lead to significant improvement in health.

The skin tests performed by allergists are for IgE Type 1 reactions are give no useful information for IgG Type 2 reactions.

In our office we test primarily for Type 2 food allergies because most people already know their Type 1 reactions. We use a Type 2 food allergy test that is highly scientific, accurate, and reproducible, having been meticulously developed over the past 20 years.

Other Diagnostic Procedures

Elimination/Reintroduction

This is considered the “gold standard” for diagnosis. It involves an elimination or oligoantigenic (few foods which do not commonly cause sensitivity reactions) diet followed by re-introduction of foods one at a time until there is a return of a symptom. The food is then avoided again, re-introduced again and if the same symptom returns you can assume you have identified the sensitizing food.. This must not be done if there is any reason to suspect an anaphylactic reaction. The test can become confusing when combinations of foods are the problem.

Challenge or provocative testing

This involves placing food extracts under the tongue or injecting them under the skin. However, this test tends to be expensive and unreliable. Provoking symptoms is not advised for patients who have experienced anaphylactic reactions to foods, insect stings, or medications.

Enzyme Linked Serum Assay (ELISA)

This correlates well with RAST but is less expensive. ELISA IgG & ELISA IgG4 measures IgG & IgG4 respectively.

ELISA/ACT (Enzyme enhanced Lymphocyte Blastogenesis Assay/Advanced Cell Test)

This test is said to give virtually no false-positives and less than .2% false negatives. It will measure delayed hypersensitivity reactions, requires a 12 hour fast and then a blood draw. The test must be performed within 72 hours of drawing the blood, assuming sample is stored between 10-30 C in all-plastic container. If you are using steroids, they must be stopped 4 days before the test; aspirin and antihistamines must be stopped 2 days before the test. This test is also expensive.

Sublingual Test

With this test, the antigen (food) is put under the patient’s tongue and the patient’s reactions are observed: wheezing, pallor, fainting etc. The patient’s subjective symptoms are recorded simultaneously. There are many false positive reactions. It is a cross between homeopathy and conventional allergy, using very small doses to try and induce a reaction. This test seems to produce the most inconsistent results. There are several negative studies including ones which showed fewer reactions to corn than distilled water and objective changes found in patients using distilled water.

Neutralization therapy

This testing involves both diagnosis and therapeutic aspects. Different concentrations of each antigen (food) are injected beneath the skin. One then observes whether there is a wheal/flare reaction (similar to what many people get when bitten by an insect such as a mosquito). The neutralization dose is the strongest dilution of antigen which does not produce a wheal/flare reaction. A study that was done in an attempt to disprove this idea , but it was found that it does work.

Scratch, Skin testing

This is used by conventional allergists. There are many false positives and false negatives. It measures only IgE mediated reactions which cause the release of substances, especially histamine (hence the use of antihistamines for many allergic patients). The histamines cause vasodilation, an increased capillary permeability resulting in a wheal and flare reaction within 15 minutes or so. With inhalants, skin testing gives fair results but with food it gives very poor results. A clinically significant response cannot be diagnosed by the presence of a positive serological or skin prick test alone, neither can the diagnosis be invalidated by their absence. Even when the food allergy is of the immediate type, skin prick test and measurement of allergen specific IgE may be negative. The test is painful and time consuming and not useful in young children. In addition, the test is influenced by drugs such as antihistamines and steroids.

Kinesiology

Used by many chiropractors, the food is placed on the patient and certain muscles are tested for strength and weakness. This test is inexpensive, fast, and gives immediate results. As yet, there are no “scientific studies”, but it definitely does work for some people.

D’Adamo Blood Type

Dr. James D’Adamo has developed diets and exercise programs for each of the four different blood types (O, A, B, AB). It is based on research that certain diseases are more common among one blood group over another and his own clinical experience. People with type O blood seem to do better if they consume flesh protein and do a lot of physical activity. Type A blood type people are primarily creative and do better with low energy food and light exercise such as yoga. They are suited to be vegetarians. Type B people are a balance between type’s O and A. They are both practical and mental and can eat from a balance of both the animal and vegetable kingdom with a mix of light exercise and more vigorous activity. Type AB are somewhere between type A and B but are often towards one type or the other and therefore some are best suited for type A diet/exercise and others are better suited towards type B characteristics. For a complete discussion of this type of evaluation read Dr. D’Adamo’s book, The D’Adamo Diet.

Electro-acupuncture according to Voll (EAV) testing

In a controlled, comparative study performed by Julia Tsuei M.D., F.A.C.O.G. between RAST, RASP, scratch, cytotoxic, food challenge and electro-acupuncture according to Voll (EAV) methods of allergy testing, EAV test results proved to be accurate and reproducible. There was a high degree of compatibility of the EAV with the other 5 tests, especially the food challenge test which is considered to be the most sensitive of the currently available tests. The study demonstrated great sensitivity.

Treatment Options Treatment Strategy

Managing food allergens or sensitivities usually means avoiding offending foods and treating symptoms when they occur. Naturopathic physicians are particularly skilled in guiding patients so that reactions are minimized, thus avoiding unnecessary food restrictions. Usually, once the food is eliminated from the diet, symptoms will abate. However, avoidance takes persistence and may not always be possible. For example, the substance may be present as an unspecified additive within another food or "hidden" in another form. Other factors such as the amount of the food, which parts of the food are used, or the way in which it is prepared can influence the systemic response. Therefore, treatment may be necessary to address occasional allergic symptoms.

Drug Therapies

Complementary and Alternative Therapies

The key to treatment of food allergy is complete avoidance of allergens for four to six months. Reducing inflammation, minimizing hypersensitivity reactions, and restoring the integrity of the digestive tract are ways in which alternative therapies may help resolve food allergies. Hypersensitivity reactions may be associated with stress and anxiety. Mind-body techniques such as meditation, tai chi, yoga, and stress management may help normalize immune function.

Nutrition

Note: Lower doses are for children.

Herbs

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, it is important to ascertain a diagnosis before pursuing treatment. Herbs may be used as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, teas should be made with 1 tsp. herb per cup of hot water. Steep covered 5 to 10 minutes for leaf or flowers, and 10 to 20 minutes for roots. Drink 2 to 4 cups/day. Tinctures may be used singly or in combination as noted.

Homeopathy

An experienced homeopath should assess individual constitutional types and severity of disease to select the correct remedy and potency.

Acupuncture

Acupuncture may help restore normal immune function and reduce the hypersensitivity response.

Massage

Therapeutic massage may help reduce the effects of stress.

Patient Monitoring

A diet based on vegetables, fruits, and high-fiber foods and one that is also low in fat and refined sugar is considered best when addressing any type of allergy. Because there seems to be a connection between the inflammatory process and animal fat, it may help to reduce consumption of animal products.

Other Considerations

Prevention

Conservative introduction of solid foods as child is weaning may help prevent hypersensitivity conditions. If there is a strong family history of allergies or atopic conditions and/or if the child's immunity has been compromised in infancy, delay the introduction of highly allergenic foods until one year or older.

Complications/Sequelae

Some research suggests a link between food allergies and celiac disease, arthritis, chronic infection, depression, anxiety, and chronic fatigue.

Prognosis

Most infants outgrow their Type 1 sensitivities to food by 2 to 4 years. Adults with food allergies tend to retain them for years. While there is no cure for food allergies, prognosis for remaining symptom-free is excellent as long as offending foods are identified and avoided and the digestive system and immune system is treated.

Pregnancy

Nutritional support may safely relieve symptoms during pregnancy.