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The Anatomy of Allergies
Why do some people suffer while others don’t?


As the seasons change, the air is filled with the ripe pollen of trees, weeds and grasses, wrecking havoc on the noses, lungs and throats of allergy sufferers. But why do some people react strongly to pollen releases while others have no reaction at all? What exactly happens to the body during an allergy attack and are there ways to minimize the misery?


Why Some Suffer & Others Don’t


If you suffer from the typical runny nose, itchy red eyes and sneezing attacks of allergies, you may have a genetic predisposition to such a reaction or have developed a sensitivity. Both genetics and environmental exposure play a role in the development of seasonal allergies.


Someone born to allergy-plagued parents is 75-80% more likely to develop allergies, whereas a person born to one allergy-sufferer, has a 50-50 chance of being similarly afflicted. Increased environmental exposure to potential allergens is another way individuals develop allergies. Prolonged or heavy exposure to pollen and other agents can cause the body to develop an exaggerated immune response.


Allergy Attacks - The Body’s Immune Response


Even though pollen is a non-threatening protein, those with sensitivities experience an immune response that is typically reserved for harmful substances the body encounters. So what causes this response?


The body’s immune system is built to recognize the difference between harmful invaders and those that are non-threatening. But when pollen enters an allergy-sensitive individual, the body’s white blood cells, called lymphocytes, go on alert and respond to the allergy agent as if it were threatening. The lymphocytes check out the invader and, over the course of 10 days, begin to build antibodies against it in the lymph nodes. These antibodies then attach themselves to what are called “mast cells” and “basophils” in the body, preparing for battle.


At the onset of another pollen attack, the antibodies attach to the foreign protein and trigger the mast cells and basophils to release chemicals called histamines. These histamines are responsible for a wide range of symptoms, including a runny nose, watery eyes, scratchy throat, sneezing, coughing and itching.


When histamines are released into the body, they dilate capillary vessels and cause a drop in blood pressure. In individuals with severe allergic reactions, these responses can reach dangerous levels, causing what’s called anaphylactic shock. This potentially life-threatening condition may also cause cell fluids to release to the point where airways swell shut and breathing is compromised. Epi pens, containing epinephrine, are sometimes carried and used by those with known severe reactions to particular allergy agents. Epinephrine counteracts the affects of histamines by constricting blood vessels. Its affects last between 10 and 20 minutes.


Characteristics of Allergy Agents


While there’s no way to avoid allergy agents 100% of the time, there are ways to minimize exposure and affects. Individuals should consult their doctors for advice on how to best manage their allergies.


Plants that rely on wind transportation for fertilization make pollen that’s made for long-distance travel, which means that eradicating an allergy agent does little good in ridding oneself of the allergy. For example, Ragweed, one of the biggest allergy villains, can produce one million pollen grains a day. Ragweed pollen has been found 400 miles away and 2 miles in the air.


So what hope do pollen sensitive individuals have?


There are a few characteristics of allergy agents that may assist allergy sufferers in avoiding days with large pollen counts. A pollen count provides a daily and regional measure of the amount of pollen in the air, represented by grains per cubic meter over 24 hours.


Pollen counts are generally at their highest on warm, dry and breezy days, as these are the ideal conditions for pollen travel. Unfortunately, these are also the days most of us would rather be outside. Wet, chilly days slow pollen travel and offer some respite to the weary allergy sufferer.


Contrary to popular belief, most ornate flowering plants do not cause allergies. Some of the plants that do include:


Weeds: ragweed, sagebrush, redroot pigweed, lamb's quarters, Russian thistle (tumbleweed), and English plantain


Grasses: Timothy grass, Kentucky bluegrass, Johnson grass, Bermuda grass, redtop grass, orchard grass, and sweet vernal grass


Trees: oak, ash, elm, hickory, pecan, box elder, and mountain cedar.


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