Allergies are an abnormal response by the immune system to specific substances known as allergens or antigens. Allergens are not normally harmful and can include foods (such as dairy products, chocolate, shellfish and wheat), drugs (such as penicillin), pollens, dust mites, mold spores, animal dander, insect venom, certain metals (especially nickel), some cosmetics, and other common substances.
Our immune system is a highly complex defense mechanism that helps us to recognize and combat “foreign invaders” such as bacteria, viruses, and parasites.
In an allergic or hypersensitive reaction, the immune system recognizes an allergen as foreign and produces an allergic type of antibody (called immunoglobulin E or IgE) to neutralize and repel the allergen. IgE triggers a special type of immune cell (called the Mast cell) which releases potent chemicals into the blood stream, mainly histamine. These chemicals produce the allergic reactions in the skin, respiratory tract, and gastrointestinal tract.
Genetics appears to be an important determinant on why many people develop allergies. A common form of allergy, called “atopy”, occurs when an allergic tendency runs in families. Atopic individuals are born with a predisposition to develop an extra sensitivity to allergens and produce too much of the IgE allergy antibody. Atopy can manifest as different allergic conditions including childhood eczema, dermatitis, asthma, hay fever, allergies, and migraines.
According to the American Academy of Allergy, Asthma and Immunology (1):
- Allergies may affect as many as 40 to 50 million people in the United States.
- 35.9 million people in the United States have seasonal allergic rhinitis (hay fever).
- 10 million Americans have allergic asthma.
- 20.3 million Americans suffer from asthma.
Allergic reactions are divided into four different categories: Type 1, Type 11, Type III, and Type IV. Type I allergic reactions are the most common and occur within minutes after exposure to a given allergen and reactions can range from mild to severe, including:
- itchy or runny nose
- itchy throat and/or ears
- gastrointestinal upset
- breathing problems
- including asthma
- swelling of the face (angioedema)
- anaphylaxis (a severe, life-threatening reaction which may include any of the above symptoms as well as irregular heartbeat, shock, seizures, and/or swelling of the throat and larynx (voice box), requiring urgent medical attention.)
Common conditions that manifest allergic symptoms include:
- Hay Fever (Allergic Rhinitis): environmental allergens (pollen, mold) can trigger allergic symptoms including nasal congestion and discharge, sneezing, itchy eyes, and tearing.
- Allergic Asthma: pollen, dust, smoke, and animal dander can trigger allergic symptoms including difficulty breathing and wheezing.
- Gastrointestinal allergies: antigenic foods can trigger allergic symptoms including diarrhea, cramping, vomiting and nausea.
- Eczema (atopic dermatitis): antigenic foods, dust, or pollen can trigger allergic symptoms including rashes and itchy, scaling patches of skin.
The best treatment for allergy relief is to first identify and avoid the known allergens responsible for causing the allergic reaction. Allergies can be identified through individual allergy testing. Methods include a skin prick test, patch testing, and elimination diets. Although it may not be feasible to avoid all antigens such as outdoor pollens, one’s personal environment can be kept free of known or potential allergens. For example, allergy- and mite-proof covers should be used on pillows. Mattresses, box springs, and air-conditioning filters should be changed regularly. Air purifiers should also be installed. Mold growth should be eliminated to help with allergy relief; and cats and dogs should be bathed frequently to reduce surface allergens on their bodies.
Many allergy relief drugs are available over the counter and by prescription. These medications reduce allergic symptoms but may have adverse effects that make them difficult to tolerate when taken over long periods. Allergy relief medications include oral antihistamines that are often combined with decongestants to relieve inflammation, congestion, and itching associated with an allergic reaction. Nasal sprays containing cromolyn sodium block the release of histamines. Other nasal sprays, which contain corticosteroids, are more commonly used for severe allergic rhinitis. Anticholinergics, beta-adrenergics, and methyl xanthine are drugs for allergenic asthma. Many allergies can also be treated with a series of allergy desensitization shots, which decreases an individual’s sensitivity to some allergens.
Essential Fatty Acids (Fish Oil, Flaxseed Oil, and Evening Primrose)
Studies show that supplementation with omega-3 and omega-6 essential fatty acids have an anti-inflammatory effect and can help control the inflammation associated with allergies. The reduction of such inflammation may help to accelerate allergy relief (2, 3). Fish oil and flaxseed oil are excellent sources of omega-3 fatty acids. Allergic individuals are often deficient in both omega-3, and gamma linolenic acid (GLA); a metabolic byproduct of omega-6 fatty acid. Supplementation with GLA’s such as evening primrose and borage oil have been shown to benefit allergic conditions such as eczema (3).
Vitamin C has been shown to have powerful antihistamine effects, including preventing histamine secretion and increasing histamine detoxification (4). Studies indicate that vitamin C supplementation decreases blood histamine levels and hay fever symptoms, both of which contribute to allergy relief (5, 6). According to Dr. Linus Pauling, a two-time Nobel Prize winner, vitamin C boosts immune function and is a natural antihistamine. It may be taken at the highest daily dose that does not cause diarrhea during the allergy season (7).
Flavonoids (Quercetin and Grapseed Extract)
Studies have shown that flavonoids such as quercetin (a bioflavonoid) and grapeseed extract (contains the flavonoid, proanthocyanidins) have potent antihistamine effects which prevent the release of histamine and other allergy-related chemicals, including leukotrienes and prostaglandins (8-12). Quercetin or grapeseed extract taken in combination with vitamin C have been found to work synergistically with vitamin C, and help to control and relieve the symptoms associated with common allergies and allergic asthma (13).
The freeze-dried leaf of stinging nettle has been shown to have anti-allergy properties (14). Supplementation with freeze-dried stinging nettle leaf is particularly effective in relieving the symptoms of allergic rhinitis (itching, watery eyes, runny nose) when combined with quercetin and vitamin C.
Probiotics (Lactobacillus Acidophilus and Bifidobacteria)
Probiotics including lactobacillus acidophilus (small bowel friendly bacteria) and bifidobacteria (large bowel friendly bacteria) are nutritional supplements containing the same beneficial bacteria that are found in the digestive tract. Probiotics are shown to enhance intestinal tract immunity, help improve digestive health. and relieve symptoms related to food allergies (15, 16).
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