Sep
08
The immune system is composed of many different organs, cells, and molecules. During an allergic reaction, the white blood cells, including T-helper cells, B-cells (which produce antibodies), and accessory cells, such as macrophages and mast cells, are involved. Antibodies are protein-based structures that bind to allergens, which are also often proteins or protein fragments themselves. The antibody that is the cause of all classic allergic reactions is IgE (Immunoglobulin E). IgE’s normal function is to fight parasites in the human body. This may be a main reason why people in developed countries tend to have more allergies than people in developing countries: the environment of developed countries is relatively parasite-free, and thus “too clean”. One of the emerging theories is that: the IgE antibodies in humans, who live in developed countries, have nothing to fight against except foreign substances in the body, such as pollen, food, and certain drugs.
During the first exposure to an allergen, B-cell bound IgE antibodies that are specific to the allergen bind to it, which then triggers a change in the B-cell to make more IgE antibodies specific to that allergen. Some of these allergen-specific antibodies end up binding to another immune cell called a mast cell, which contains large amounts of the inflammatory hormone histamine. Mast cells are found both in mucous membranes, such as on the mouth and lungs, and also in connective tissue. However, during the first immune reaction, the IgE antibodies will simply bind on the surface of mast cells and sit there, waiting for the second round of allergen to bind to the antibody on its surface. When a second allergen exposure occurs, the immune system is ready for the threat: the allergen will bind to IgE antibody on the mast cells, which then are programmed to release inflammatory molecules, including histamine. Histamine is a main cause of allergic symptoms.
The four common allergic reactions are: food allergies, bronchial asthma, atopic dermatitis (eczema), and rhinitis, or hay fever (1); the two main topics in this article will focus on food allergies and bronchial asthma. Only about 1% of Americans have a true food allergy (2), but they can be a serious problem for those who have them. As the Roman Lucretius said in 50 B.C. “What is food to one person may be bitter poison to others”. This saying has later evolved into the more current one: One man’s food is another man’s poison. The most common food allergens are: eggs, wheat, and cow’s milk. Yeast and yeast-containing products, pork, beef, and corn are also common allergens.
Allergy to pork and beef may actually be sensitivity to the inflammatory fats in those foods. There could also often be a sensitivity to additives in the foods above, such as monosodium glutamate (MSG), aspartate and/or phenylalanine (Nutrasweet), nitrates and nitrites, or sulfates and sulfites. In addition some foods and drinks such as strawberries, chocolate and coffee may not be true allergens, but may contain a good amount of the inflammatory hormone histamine. Foods and drinks like those mentioned above may also contain chemicals that trigger histamine release in the body through non-traditional allergic pathways. Interestingly, alcoholism may be linked with food allergies (3). There are several theories for the origins of chemical sensitivity, including: enzyme damage and/or depletion, pollution, immune-system-mediated damage, yeast overgrowth (candidiasis), chronic inflammation, carbon monoxide poisoning, and sensitization of key parts of the nervous system (4).
Allergies may also be worsened by incomplete digestion of food, particularly protein. Normally, proteins are digested in the stomach into very small chains of amino acids, which are further degraded into individual amino acids in the small intestine. The amino acids are then absorbed in to the bloodstream. The immune system does not react against individual amino acids. In fact, the smallest amino acid chain (called a peptide) that can be recognized by an antibody are three linked amino acids. However, incomplete digestion in the stomach and small intestine may not be able to break down all proteins into individual amino acids. If there is any “leakiness” in the wall of the small intestine, some of the small peptides could enter the bloodstream later. Since the immune system is not trained to recognize these food peptides as harmless, it may initiate an allergic reaction against them. The above sequence of events is termed the “leaky gut syndrome” by holistic practitioners. Yeast may also contribute to leaky gut syndrome, since they can assume a mycelium form that can branch out into the intestinal walls (4).
If you suspect a food allergy, you can test for it at home. Take your resting pulse before a meal by putting your index and middle finger on the side of your other wrist. Look at a clock and count the pulse beats in one minute. Eat a small portion of the suspected food, wait twenty minutes, then take your pulse again for one minute. If your resting pulse has rose more than ten beats per minute, you are probably allergic to at least one of the ingredients in your last meal. Food allergy testing can also be done by eliminating a suspect food for several days or weeks, then reintroducing the food and observing any reactions. This technique is relatively safe, but may take a long time to complete, since only one type of food at a time can be reintroduced. A food rotation diet can also be tried, where foods that cause only mild to moderate reactions are eaten only once every 3-4 days. This allows the body and the immune system to recover somewhat between offending foods. I personally do not food rotation diets, unless the person has too restricted of a diet and must eat some allergenic foods.
Technologically speaking, conventional allergy testing is in many ways still in the stone age. The two main types of allergy tests are the skin test and the blood test. Skin tests may be more accurate than blood tests. However, a control for the skin test is often phenol, which is a highly toxic and carcinogenic chemical. Inhalation tests with the irritant Methacholine can determine how reactive a person’s airways are. Not only can this chemical induce asthma and related breathing problems, it can also be fatal. Some conventional allergy treatments can also be dangerous. Desensitization treatments involve either oral or injected allergens to hopefully produce a tolerance to the allergen. Unfortunately, desensitization therapy has also caused fatalities.
There are many different nutrients that can help relieve allergies and asthma. Vitamin C indirectly inhibits mast cells from releasing histamine (5). The bioflavonoid quercetin has antihistamine activity, but it is not easily absorbed (6). A magnesium deficiency can aggravate allergies (6). Unfortunately, many allergy medications lower magnesium levels (7). Some nutritionists and doctors believe that taking vitamin B3 (niacin) is useful for people with allergies. Niacin releases histamine, often causing a reddened facial flush soon after the vitamin is ingested. Repeated dosing with niacin may eventually lower the body’s stores of histamine. In theory, this may then lower the intensity of any allergic reaction in the future (3). The above natural therapies have obvious advantages over many of the synthetic antihistamines on the market, such as Benadryl. One study found that driving after taking the first-generation antihistamine Diphenhydramine (Benadryl) can cause impairment equivalent to driving drunk (2).
There is a theory of cerebral allergies, in which allergens cross the blood-brain barrier. The resulting allergic reactions can such symptoms such as: headache, anxiety, dizziness, and depression (3). Since children do not have a completely formed blood-brain barrier, they may be particularly susceptible to cerebral allergies. This may lead to behavioral problems and inability to cope with stress (8). In fact, one of the most important things a person with allergies can do is avoid stress. Stress itself can cause the internal release of histamine (9).
Many inhaled allergens cause symptoms of coughing, difficulty breathing, and wheezing. These are symptoms of bronchial asthma. Asthma is the leading cause of chronic illness in children (2). About 30% of asthma is caused by non-immune reactions, including: cold, drugs, and even exercise (1). Antihistamines are not used to treat asthma (asthma is usually treated with either steroids or stimulants). Many people take bronchodilators to open up their airways during an episode of asthma; however, this is increasingly being discouraged. Overuse of bronchodilators can cause desensitization of the drug receptors (drug tolerance), which means a person must use more and more of the inhaler to get the same airway-opening effect. In some cases, when a person really needs the bronchodilator to work, it may not, and the person can die. In fact, asthmatics who frequently use bronchodilators are 2 ½ times as likely to die from an asthma attack as asthmatics that don’t use a bronchodilator (10). As you have read from the information above, there are many natural alternatives for drug use to control allergies and asthma. A person with allergies and/or asthma has to work hard to find the sources of their condition, but in the end it is worth their time and effort.
References:
1 Abbas, A., Lichtman, A. & Pober, J. Cellular and Molecular Immunology, 4th Ed. Philadelphia, PA: W.B. Saunders Company, 2000.
2 Litin, S., ed. Mayo Clinic Family Health Book, 3rd Ed. New York, NY: HarperCollins Books, 2003.
3 Haas, E. Staying Healthy with Nutrition. Berkeley, CA: Celestial Arts, 1992.
4 Gibson, P. Multiple Chemical Sensitivity: A Survival Guide. Oakland, CA: New Harbinger Publications, Inc., 2000.
5 Nandi, B., Subramanian, N., Majumder, A., & Chatterjee, I. (1974). Effect of ascorbic acid on detoxification of histamine under stress conditions. Biochemical Pharmacology, 23, 643-647.
6 Feinstein, A. Healing with vitamins. Emmaus, PA: Rodale Books, Inc., 1996.
7 Reavley, N. The New Encyclopedia of Vitamins, Minerals, Supplements, and Herbs. New York, NY: M. Evan & Co., 1998.
8 Calam, R., et. al. (2003). Childhood asthma, behavior problems, and family functioning. Journal of Allergy and Clinical Immunology, 112, 499-504.
9 Brown, R., Stevens, D., & Haas, H. (2001). The physiology of brain histamine. Progress in Neurobiology, 63, 637-672.
10 Vayda, W. Attack Asthma: How to Conquer Environmental Illnesses and Allergies Without Drugs. Port Melbourne, Victoria, Australia: Griffin Paperbacks, 1994.