Understanding Food Allergies

 

 

 

 

 

 

 

Food allergies, food intolerances and food sensitivities – all terms that are getting more play in the holistic nutrition and naturopath communities. They are said to play a role in chronic conditions. But where we notice them most is the way they disrupt our digestion and dampen our energy.  They can cause a low level stress response in our body, wearing us down in subtle ways.  But how do they differ? 

• Food allergies are the nasty fast-acting reactions to foods like peanuts, eggs, cow’s milk, fish and shellfish.  The immune system sees the food as an invader, immediately forming immunoglobin E (IgE) antibodies that can cause the skin and mucous membranes to swell.  In severe reactions, blood pressure may suddenly drop, causing anaphylactic shock.
• Food intolerances and sensitivities are more subtle. The immune system may respond by developing IgG or IgA antibodies, but the reactions can be delayed by weeks.  Symptoms come on gradually and you may need to eat larger amounts of the troubling food for it to have an effect on your system.  Commonplace symptoms are indigestion, gas, chronic fatigue, skin rashes, joint aches and pain.   

Since food is one of the key ways that we interact with our environment it makes sense to observe the effects of what we’re eating every day. According to Dr. James Li, asthma and allergy specialist at the Mayo Clinic, causes of food intolerances include:

• Absence of specific digestive enzymes. Lactose intolerance is caused by insufficient amounts of the enzyme lactase, which is needed to digest the sugar in milk. Symptoms are bloating, abdominal pain and diarrhea when consuming milk.
• Sensitivity to food additives. For example, sulfites used to preserve dried fruit, canned goods and wine can trigger asthma attacks in sensitive people. Amines (found in bananas, tomatoes, avocados, mushrooms, wine and Parmesan cheese) can cause irritation of the skin, mouth, stomach and intestinal track, hives, mouth ulcers, or nausea and stomach cramps.
• Celiac disease.  Celiac disease has features of a true food allergy because it does involve an abnormal response of the immune system. Symptoms are mostly gastrointestinal, and people with celiac disease are not at risk of anaphylaxis. This chronic digestive condition is triggered by eating gluten, a protein found in wheat and other grains.
• Other food sensitivities. In some cases, food intolerances are due to physical or emotional stress or exposure to environmental toxins rather than a reaction to the foods themselves.

 

Testing for food intolerances

The gold standard for identifying food intolerances is the elimination diet followed by a challenge diet to see whether a suspect food really does set off a reaction.  The test is simple, but that doesn’t really mean that it’s easy.  If your symptoms are severe it is best to work with a qualified nutritionist recommended by your doctor.

The first step is to eliminate foods that are major triggers.  The list of forbidden foods is lengthy:  dairy products, wheat and other gluten-like grains, eggs, corn soy and soy products, peanuts, citrus fruits, yeast, refined sugars and artificial additives, preservatives and colorings.  All these foods are eliminated for at least two weeks.  It’s recommended to keep a food diary of what you are eating and when to identify any allergens that you eat by mistake.  Better still is to include any instances of the common symptoms of intolerance, like fatigue, digestive disturbances and skin issues.

The second step is to add back the foods one at a time into your diet to see if symptoms recur.  It’s important to add the foods back one day at a time so you can pinpoint the offenders.  Once symptoms are associated with a food or food group, the intolerance can be confirmed with a challenge – eating the suspected food and then watching to see if symptoms develop. 

Overall, the program takes about a month of carefully monitoring your diet.  What may help you stay motivated is that clinical trials using food elimination diets have reported improvement rates as high as 58% for atopic dermatitis, 71% for irritable bowel syndrome (IBS), and 90% for migraines.[1]

If you are working with a complementary practitioner they may recommend other tests: an IgG anti-food blood test or muscle strength training (applied kinesiology).  These tests do not have the clinical support that the elimination diet does and are generally not supported by physicians.  Dr. Randy Horwitz, an immunologist at the Arizona Center for Integrative Medicine at the University of Arizona, notes that when food sensitivities – not true allergies – are a problem, traditional allergy tests often yield negative results. He says that in his practice he has not seen uniformly good results with any of the other tests. Results “go all the way from questionable to downright useless,” he says. Still, there are people who swear by these tests and they have found significant improvements in energy when they eliminate the foods that were identified.  They may be worth the cost if you don’t have the ability to closely manage your diet for a month, or you are concerned about a child or parent who is suffering from symptoms.