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How the Immune System Affects Asthma



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The body's first line of defense against any foreign invader such as germs or bacteria is the immune system (a complex group of cells and organs that fight against infection and other harmful particles). When the immune system is weakened or impaired in any way, it goes out of whack, responding negatively to substances that are normally harmless to the body. Symptoms of asthma or allergy are two disorders linked to the immune system.

Many people who are asthmatic are atopic. That is, they have inherited a disposition towards allergy. Having asthma causes the airways to be inflamed or swollen. As such, they are very sensitive and react strongly to the presence of irritants or allergens. This response to allergens narrows the airways, limiting air flow to lung tissues. It causes a whistling sound called wheezing. When the immune system becomes overly reactive towards these allergens, it becomes weakened. In this state, asthma symptoms are usually worse.

Allergic reactions tend to manifest in three stages: sensitization, early phase response, and late phase response. To develop an allergy, a person has to be exposed to the allergen first. With initial exposure, symptoms may not surface right away. However, this first exposure is already starting a domino effect, a chain of events called the allergy cascade. The next time a person is exposed, these events will go into action and produce allergy symptoms.

Sensitization:

By inhaling substances such as pollen, pet dander, or dust, these materials can bind to membranes of the lungs. The cascade effect begins when the immune system perceives these particles as being foreign objects, and begins a plan of attack, a series of cellular chain reactions. The immune system stimulates several types of immune cells to activate.

T cells stimulate B cells, which in turn transform into plasma cells. ( T, B, and plasma cells are white blood cells). These plasma cells produce antibodies (proteins used as detection/response devices by the immune system) that are specific to the antigen (toxins or foreign substances), binding themselves to mast cells (connective tissue frequently injured in allergic reactions).

Though the allergen has triggered an allergy cascade, asthma symptoms may not surface until subsequent exposures, perhaps in the early phase response.

Early Phase Response:

This is where mast cells release anti-inflammatory cells called mediators, one of which is histamines. Histamines will travel the body to fight off invaders like bacteria and viruses. In the early phase, people with asthma will begin to experience the body's overreaction to allergens. Symptoms of coughing, wheezing or being short of breath come about. These immunological responses cause airways of the lungs to swell and become narrower. This allergic response can be accompanied by a runny nose or itchy/watery eyes. Symptoms usually appear shortly after re-exposure, lasting 3-4 hours.

Late Phase Response:

Symptoms in the late phase response may not appear for several hours but can cause the release of another kind of immune cell called Eosinophil. Eosinophils are normally released by the immune system to fight off infection. In the case of asthma, these immune cells cause more inflammation and make allergic symptoms much worse. Even though symptoms may be slow in appearing at this stage, this stage can last as long as 24 hours. Compared to symptoms of early phase, inflammation and obstruction of airways are much more severe.

Treatments for Asthma:

Avoidance - The best method for treatment of asthma is avoidance of allergens, such as food and/or pets. These are choices a person must make. However, allergens like dust and mold cannot always be eliminated from a person's environment; in this case, medication might be necessary.

Antihistamines - Asthma can be treated with antihistamines such as Benadryl, Claritin, or Zyrtec. These work by inhibiting the inflammatory response of mediators released in the early phase, thereby preventing allergy symptoms. Antihistamines prevent histamines from binding to receptors in the eyes and nose, where symptoms of sneezing, runny nose, watery eyes, and congestion result.

Bronchodilators - Bronchodilators such as Albuterol target early phase asthma by opening airways and clearing airway obstruction, making it easier to breathe.

Steroids/Leukotriene Antagonists - These are drugs with anti-inflammatory properties. They decrease late phase responses or prevent late phase responses from happening.

Allergy Shots/Immunotherapy - This treatment is used to desensitize the patient against allergens. This method is designed to decrease the foreign invader response; have the immune system produce less antibodies; or have  the body not react as strongly to particular allergens. 

Diet:

Besides medication, there are other elements such as diet and exercise to strengthen the immune system and lessen the severity of asthma symptoms. Studies have shown that nutrition and nutritional deficiencies play a major role in a immune system strength, having an impact on genes that cause inflammation and disease. People who are asthmatic tend to be deficient in a variety of nutrients, or appear to have a higher than average demand for those nutrients, in order to function well.

Good Fats - One study has determined that 40% of asthmatic children are low in levels of Vitamin D and E (fat soluble vitamins). Other good fats such as Omega 3 essential fatty acids have been shown to improve exercise-induced asthma, or steroid-resistant asthma. They are called essential fatty acids because they cannot be manufactured in the body and are needed daily for good health. Sources of Omega 3 come from beef, dairy products, eggs, walnuts, salmon/sardines/anchovies, along with fish oils and flax seed oil.

Recent studies have shown that Vitamin D deficiencies in women during pregnancy can be linked to offspring with asthma. Children with asthma who are also low in Vitamin D tend to have more flare-ups. It is also thought by researchers that Vitamin D may even control the gene responsible for asthma.

Vitamin E - Higher concentrations of this vitamin are associated with a lower frequency of allergen sensitization, especially for people with asthma or other allergies. Natural sources for Vitamin E are green leafy vegetables, nuts and seeds, whole grain foods, vegetable oils and nut oils.

Vitamin A - Severity of asthma symptoms can be related to low levels of Vitamin A. To get enough of this daily nutrient, aim for colorful foods that contain carotenoids: yellow/orange/red colored foods, for powerful beta carotene and antioxidants. These can be found in liver, egg yolks, carrots, mangoes, sweet potatoes,etc.

Antioxidants - Oxidation by various bodily processes causes aging and production of free radicals which cause cell/tissue damage. For asthmatics, oxidation occurs very rapidly in the airways when responding to an allergen. Fresh fruits and vegetables are a great way to get one's daily allowance of antioxidants.

Vitamin C - has been linked to asthma. Although it does not improve asthma symptoms, it does improve lung function, being a powerful antioxidant.

Magnesium - Studies have shown that low levels of magnesium are connected to various lifestyle diseases, including asthma. Since magnesium is rarely found in Western diets, eating foods high in magnesium may help people with asthma. Aim for green leafy vegetables, legumes, whole grains, and fish.

B vitamins/Selenium/Zinc - Low levels of these vitamins have also been associated with asthma. No studies have been done to show improvement of asthma, but they are important in immune system functioning.

Coffee contains certain components that significantly reduce symptoms of asthma, because it acts as a bronchodilator. As well, apple juice has antioxidant qualities, so drinking a glass a day may help with symptoms. One can see how a better understanding of the immune system helps to gain better control over the symptoms of asthma.

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  • InfoBoxCallToAction ActionArrowhttp://goldbamboo.com>conditions>A>Asthma
  • InfoBoxCallToAction ActionArrowhttp://nlm.nih.gov/.../immunesystemanddisorders.html
  • InfoBoxCallToAction ActionArrowhttp://asthma.about.com/asthmabasics/a/Asthma_Immune.htm
  • InfoBoxCallToAction ActionArrowmedterms.com/script/main/arti.asp?articlekey=4291
  • InfoBoxCallToAction ActionArrowhttp://easy-immune-health.com/Asthma-and-Nutrition.html