Food Allergies and Sensitivities
An allergic reaction is an immune response to a foreign substance (antigen) that results in inflammation and organ dysfunction. Allergens can be chemical, environmental or food-based. In people with food allergies/sensitivities, an immediate or delayed adverse reaction by the immune system can occur to a food that most people find harmless.
A food allergy is a classic antigen-antibody response to a particular food (IgG or IgE are the usual antibodies involved).
A food sensitivity is an adverse reaction to a food with no antigen-antibody response.
1. Immediate: IgE-Mediated Response
An IgE-mediated allergic response is an immediate reaction within two hours after eating food. IgEmediated reactions are mainly seen in airborne allergies (pollens, dusts and weeds), and are not seen as often in food allergies.
MODE OF ACTION: IgE antibodies attach to mast cells that are mainly found in the air passages, blood and skin. When an allergen enters the body, the mast cells release substances (i.e. histamine) to ward off the allergen.
2. Delayed: IgG-Mediated Response
An IgG-mediated reaction is a delayed response, usually 36-72 hours after exposure to an antigen. IgG-mediated reactions are seen in most food allergies. The delayed response makes it difficult to pin down the specific food allergy.
MODE OF ACTION: A different type of mast cell is found in the connective tissue lining the intestinal tract. A food allergy reaction starts in the digestive tract, triggered by a free-floating antibody called secretory IgA. Secretory IgA functions to protect the lining of the small intestine by secreting a thick protective coating of mucus from the mucosal lining when it comes in contact with a food allergen. If the food is eaten repeatedly, the immune system is overtaxed and the amount of secretory IgA antibodies produced is decreased. This allows the food to come in contact with the mast cells and triggers the release of toxic chemical mediators (histamine, leukotrienes, inflammatory prostaglandins, etc.). Over the long term, the inflammatory prostaglandins decrease HCl (hydrochloric acid) secretion, which triggers the pancreas to underproduce bicarbonates and pancreatic enzymes. Also, the chemical mediators weaken the mucosal membrane of the intestinal wall and allow partially digested food to pass into the bloodstream. The IgG antibody attempts to clear these macromolecules from the bloodstream, but if overwhelmed, these macromolecules (immune complexes) penetrate the capillary walls and are deposited in the tissues. Inflammation is produced wherever the immune complexes are deposited. (Braly, J., M.D., Dr. Braly's Food Allergy and Nutrition Revolution. 1992. Keats Publishing, Inc., New Canaan, CT., pp. 69-72).
Signs and Symptoms
1. Immediate: IgE-Mediated Response I don't have these...
- Anaphylactic shock (most severe)
- Difficulty swallowing.
2. Delayed Reactions: (IgG-Mediated Response) I DO however have a some of these, the colored ones
- Gastrointestinal complaints including stomach pains, heartburn, excess gas, chronic diarrhea/constipation, irritable bowel syndrome, ulcers and malabsorption problems
- Dark circles under the eyes.
- Chronic fatigue.
- Joint/muscle pain.
- Puffy eyes.
- Chronic swollen glands.
- Headaches (migraines).
- Canker sores.
- Chronic infections.
- Frequent ear infections.
NOTE: Offending foods can be masked because eating the food can actually make the person feel better initially. (interesting!) Endorphins, which are produced in response to the inflammation, can cover up ill feelings. If a person stops eating the offending food, they will feel withdrawal symptoms (lasting approximately one to five days). Thus, they unconsciously crave the allergy food(s) in order to avoid the withdrawal symptoms. Frequently, a person's favorite foods are the allergy foods. Also, certain foods may work synergistically, meaning they will produce symptoms when eaten together, but not when eaten alone (i.e. eggs and apples).
Possible Causes or Contributing Factors
1. Weakened immune system - may be due to increased T-cell levels because of the constant internal battle, which causes allergic reactions to be triggered more quickly.
2. Environmental toxins (metals, chemicals, other pollutants) can increase the susceptibility to allergies
3. Repetitive immunizations or antibiotic/steroidal medication that decrease immune response and disturb the normal gastrointestinal flora can increase risk of food allergies
4. Dysbiosis such as candida, parasites, fungi, etc., decrease efficiency of the gut mucosa and increase the potential for allergies
5. Children born to parents with allergies have an increased chance of developing allergies themselves
6. Repetitive ingestion of a small variety of foods (monotonous diet) causes the body to become sensitized to the foods.
7. Genetic manipulation of foods and chemicals/pesticides added to foods increases the potential of food allergies
8. Nutritional deficiencies can increase the potential of food allergies.
9. Leaky gut syndrome can cause partially digested foods, virus and bacteria to enter the blood and cause immune responses. Leaky gut is caused by weak digestion, NSAIDS, infections, alcohol abuse, nutritional deficiencies, drug/medication use or abuse, dysbiosis, stress, premature birth and radiation. The inflammation from a food allergy can open holes in the gut lining through tight junctions. NOTE: NSAIDS increase the possibility of food sensitivities because they increase permeability and the ability of food particles to cross the gut mucosa into the bloodstream.
10. Stress and physical and/or emotional trauma can be due to decreased immune function, adrenal response and possibly decreased HCl production. Allergy sufferers, "seem to have a significantly lowered threshold to stress, in part because of the physiological and psychological overstimulation of their adrenals" (Braly, J., M.D., Dr. Braly's Food Allergy and Nutrition Revolution. 1992. Keats Publishing, Inc., New Canaan, CT., pp. 68-69). One study showed that in solving a simple math problem, Type A personalities (tense, impatient, ambitious) have forty times as much cortisol and three times as much adrenaline circulating in the blood as Type B (more relaxed) people solving the same problem (Ibid, pp. 68-69).
11. Lower IgA levels (IgA protects the mucosa of the intestinal tract) increases the possibility of food allergies.
12. Poor digestion (i.e. decreased HCl production, pancreatic enzyme deficiency, gallbladder problems) increases the possibility of food allergies. Food sensitivities are frequently associated with low HCl levels.
13. Poor liver function can increase food allergies due to its role in removing foreign protein from the body and detoxifying the system.
14. Premature babies have increased risk due to underdeveloped gastrointestinal tract.
15. Premature weaning of infants to solid foods when the gastrointestinal tract is not fully developed increases the potential of food allergies. Baby formulas and cow's milk contain large molecules that are difficult for the baby to digest. Also, not breastfeeding can be a trigger for potential food allergens because of decreased protective factors from mother's milk.
16. Food additives (i.e. yellow dye #5 (tartrazine) and benzoates), which have been shown to increase the number of mast cells produced in the body, can increase the susceptibility to allergies.
17. Poor thyroid function increases allergy potential.
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