Food Intolerance: Is What I’m Eating Hurting Me?
Food intolerance and sensitivity are terms used interchangeably when referring to troublesome, but non-life threatening responses to ingested food. The World Allergy Organization defines food intolerance as reactions which are not regulated by the immune system, such as lactose intolerance (lack of an enzyme to digest lactose, a milk sugar) or reactions to food additives like sulfites or artificial colors. Food allergy, in contrast, causes immediate and possibly life-threatening reactions by the immune system. The World Allergy Organization definition of food intolerance is not consistent with how the term is used among natural health practitioners. For the purpose of this article, we will define food intolerance and sensitivity as non-allergic responses of the body to ingested food, which involve the immune system.
Celiac disease (CD) is a form of food intolerance, as it is not a true allergy to gluten. In CD, the immune system produces antibodies to gluten, which attack the cells of the body. This is the most serious form of food intolerance and requires life-long avoidance of gluten. The prevalence of CD in the United States is estimated at around 1%, which is 1 person out of 100 people. While having a first degree relative with CD increases the chances of developing the condition to 20% or more, it is still fairly rare.
Food allergies are estimated to affect 4% of the U.S. population, the majority being young children. Food allergy causes an immediate-hypersensitivity response by the immune system. This is characterized by production of IgE, which is an immunoglobulin or antibody. Antibodies target antigens, which are toxins or other foreign substances that cause an immune reaction in the body. IgE triggers a massive release of histamine and other inflammatory chemicals. These chemicals have the specific action to increase blood flow and to aid the body in ridding itself of foreign substances. Symptoms of food allergy include hives, swelling of the tongue or lips, shortness of breath, and wheezing. Anaphylactic shock, the most severe allergic reaction, requires immediate administration of epinephrine and can cause death if not treated.
Food intolerance, or sensitivity, is more common than food allergy. It is hard to estimate how common because there are multiple pathways of the immune system that are involved. The symptoms of food sensitivity vary. Digestive symptoms include diarrhea, constipation, gas, and bloating. Congestion, post-nasal drip, eczema, asthma, joint pain, fatigue, and headaches are also common. Symptoms may come and go, making them hard to pinpoint. Antibodies such as IgG and IgA form immune complexes with food proteins and trigger inflammatory reactions in the body. Symptoms can develop within a few hours to a couple of days. Food intolerance testing has been used for many years by naturopathic physicians and other natural health practitioners as a reliable indicator of foods causing adverse reactions in the body. This is especially true when testing for CD or food allergies are negative.
Common Symptoms of Food Intolerance
- Joint and muscle pain
- Allergy symptoms
Common food intolerances include wheat/gluten, dairy, eggs, corn, and soy. Most of the time there are reactions to multiple foods. It is not uncommon to see elevated antibodies to tomato, citrus, nuts, peanut, yeast, grains, coffee, and even protein foods such as chicken, beef, and seafood. Most food intolerance or sensitivity tests offer panels of 90 or more foods.
Common Food Intolerances
- Wheat/ gluten
- Cow dairy
Elevated Food Reactions and “Leaky Gut”
Antibodies to food may be elevated due to “leaky gut”. Leaky gut refers to dysfunction of the barrier function of our digestive tract, which separates the contents of the stomach and intestines from the interior of the body and blood vessels. Picture the digestive tract as a long tube that connects with the outside at both ends. Even though the tube is on the “inside” of the body, the contents are on the “outside” of the body. There may be spaces or gaps in the wall of the tube through which food proteins travel into the body. Once inside, they trigger the immune system to make antibodies. When functioning properly, the barrier cells of the digestive tract protect the body from bacteria and viruses. They also keep food proteins inside until the nutrients are digested and absorbed by the cells of the body.
Elimination Diet and Challenging
Infrequent ingestion or consuming a small portion of a food may not be enough to cause a reaction when sensitivity is present. That is why testing foods (called challenging) following an elimination diet, is the most effective way to identify food sensitivities. An elimination diet is usually done after food sensitivity testing. A minimum of 6-12 weeks is required to eliminate foods from the diet before challenging them. Foods are challenged one at a time in order to identify the reaction of that particular food. When significant symptoms are elicited by a certain food, long term avoidance is recommended. Sometimes the symptoms are minimal. Those foods can often be brought back into the diet on a rotation basis with no problem. This is not true for CD. It can take up to 6 months for the body to heal after exposure to gluten.
Food intolerance and food sensitivity are terms used to describe non-IgE antibody reactions to food. The World Allergy Organization considers food intolerance to be only non-immune reactions such as lactose intolerance. Food sensitivity testing is a way to identify hard to pinpoint food reactions that are not related to allergies, CD, or lactose intolerance. The symptoms of food sensitivity may not be consistent and are hard to identify without an elimination diet and subsequent challenging. The amount and the frequency that a food is ingested may determine how prominently symptoms appear. Symptoms of food intolerance include: digestive problems, headaches, congestion, post-nasal drip, eczema, joint pain, and fatigue. Those who test negative for CD may still have significant food sensitivities, including to gluten. This means that gluten avoidance may still be recommended, even when complete elimination is not necessary. For somebody who has been from doctor to doctor and not yet found the cause of their troublesome symptoms, food sensitivity testing is an option. Hopefully the next visit is to the naturopathic physician.
Dr. Stacey Munro is a Naturopathic physician who specializes in prevention and treatment of chronic health conditions. Following Naturopathic philosophy, she looks for the root cause, rather than just treating symptoms. Dr. Munro prescribes dietary and lifestyle changes, nutritional supplements, herbs, and other natural therapies. Nature’s Helper Medical Clinic 178 Mountain Road, Suffield, CT (860) 758-7808 www.NaturesHelperMedical.com.