Allergies, Intolerances and Gut Dysbiosis
By Hannah KayeIntroductionOver the course of a lifetime, your digestive system processes many tons of food, representing the largest antigenic (stimulating an immune response) load confronting your immune system. Figures range from 30-60 tons of food consumed in a lifetime of the average well-nourished adult. If you think about our food chain today, and the level of contamination, that’s a hefty amount of potentially harmful substances consumed on a daily basis.
Digestion, immunity & allergiesDuring digestion, proteins are broken down into amino acids in the stomach and small intestine. This digestion is essential as it removes or decreases their antigenic potential. In a healthy intestinal tract, more than 98% of ingested food antigens are blocked from entering circulation by a host of gastrointestinal protective functions. In a compromised environment with poor digestion and increased intestinal permeability, significantly more antigens may enter into circulation. These protein fragments, recognised as foreign molecules by the body, stimulate an immune response.
The immune system is a complex one that detects elements that could cause harm and responds accordingly. When the immune system is triggered, antibodies known as immunoglobulins are released. They come in various guises, and in the case of a classic food allergy, specific immunoglobulins E (IgE) are released. These cause an allergic reaction (or type-1 hypersensitivity) which can be quite robust, leading to inflammation which in turn can cause several responses, ranging from sneezing and swelling to vomiting and, in very extreme cases, death.
Yet, not every adverse response to food qualifies as an immunologically-mediated food allergy. By definition, an immune response only occurs when an antigen/antibody reaction has taken place. Food sensitivities (e.g. preservatives, additives, MSG, sweeteners, aspartame, sulfites, etc) tend to be either IgE-associated and delayed onset (atopic dermatitis), or cell-mediated and both delayed and chronic (coeliac disease). Therefore, if a person does not have antibodies against a specific food antigen, he or she cannot have an allergic reaction to that food.
However, it is possible to respond to food in non-immunological ways. A simple example is lactase insufficiency, which underlies lactose intolerance. This is when you lack (or have significantly reduced amounts) of the enzyme lactase, which is essential for breaking down lactose, the sugar in milk. This is not considered an allergic reaction and many food reactions fall into this category.
Many allergic responses to food appear to involve some form of prolonged or delayed reaction to allergens. Although controversial, there appears to be some evidence for a role of Immunoglobulins G (IgG) antibodies in the provocation of these. In some circles, it is believed that IgG may be a possible causative factor in conditions such as atopic dermatitis, asthma and IBS.
Testing for allergies & intolerancesThe underlying mechanisms that elicit food-intolerant or allergic responses are complex and controversial, and a variety of assessment techniques have been developed.
In orthodox medicine, either skin tests or allergen-specific serum IgE measurements (RAST) are used in diagnosis of true IgE allergies. CAST (cellular antigen stimulation test) testing is used to confirm sensitivities to food additives (colourants, flavourants and preservatives).
Diagnostic tests frequently used in alternative medicine such as vega test, applied kinesiology, leucocytotoxic tests and IgG intolerance tests are very much frowned upon by allergists and immunologists. This is because double blind studies have failed to find any diagnostic value in this type of testing.
Unfortunately, when considered as a whole, no test is completely adequate. Apart from the case of a classic IgE food allergy, it appears that the most cost effective and accurate avenue to determine food reactions is either an elimination or oligoantigenic diet. The oligoantigenic diet contains of only those foods known to pose little risk of an allergic or intolerant reaction.
Top 10 problem foods: | 1. | Cow’s milk |
| 2. | Dairy products |
| 3. | Wheat (and other gluten grains) |
| 4. | Fish and shellfish |
| 5. | Citrus fruits (particularly oranges) |
| 6. | Tomatoes |
| 7. | Eggs (yolk and/or whites) |
| 8. | Soya milk and related products |
| 9. | Nuts (especially peanuts) |
| 10. | Sesame seeds |
Gut floraAll too often, gut flora assessment is overlooked as a significant source of information when it comes to diagnosing and treating health problems – in particular, reactions to foods.
The number of bacteria in the large intestine alone is greater than 100 billion, which is more than the total number of cells in the human body. These bacteria constitute a powerful chemical factory and can have important effects on human physiology depending on their activities. Intestinal bacteria produce toxins and antitoxins, alter chemical composition of foods and drugs, produce and degrade vitamins, produce short-chain fatty acids from fibre, degrade dietary toxins, and inhibit the growth of certain pathogens.
Which is why, when problems with gut flora exist, there can be serious implications for the digestive tract. Not least, the development of intestinal permeability, which may be the cause of a range of food reactions. Whilst removing suspect foods may help, it won’t actually treat the underlying problem. Until you restore gut flora and heal the lining of the digestive tract, you will never achieve long-term results.
SymptomsFood allergies and sensitivities certainly account for a diverse range of symptoms from migraines and skin problems, to cardiovascular effects and gastrointestinal disorders. Please see the table below for a detailed list.
Symptoms and diseases associated with food allergy and intoleranceSystem | Symptom / Disease |
Cardiovascular | Oedema, irregular heart rhythm, spontaneous bruising, urticaria, vasculitis |
Gastrointestinal | Canker sores, celiac disease, chronic diarrhoea, colic, constipation, Crohn’s disease, gas, gastritis, IBS, nausea, recurrent mouth ulcers, stomach ulcers, ulcerative colitis, vomiting |
Genitourinary | Bed wetting, chronic bladder infections, frequent urination |
Immune | Serous otitis media |
Mental/emotional | ADD/ADHD, anxiety, depression, epileptic seizures, memory loss, schizophrenia |
Musculoskeletal | Joint pain, myalgias, rheumatoid arthritis |
Respiratory | Asthma, chronic or allergic sinusitis, constant runny nose or congested nose, nasal polyps |
Skin | Eczema, itchy skin, psoriasis, itchy eyes, urticaria |
Miscellaneous | Migraine headaches |
ConclusionIdentifying food-associated allergies and intolerances is an important step to resolving health problems. Yet, it is not the only step. Ignoring problems that may exist within the gut environment itself, means that any success you do have, will be short lived.
References
1. Liska DJ, Lukaczer D. Gut Restoration and Chronic Disease. JANA. 2002;5:20-33
2. Jones DS, Quinn S (eds) (2005) Textbook of Functional Medicine. Institute of Functional Medicine.
