By Asha Kreiling
Nowadays, it seems that almost everyone is allergic to something or at least gets a little sniffly during allergy season. Well, it’s true: more Americans than ever are suffering from allergies. Studies reveal that the prevalence of allergies, seasonal and all other types, has been increasing in recent years. Not so clear is what exactly is causing this increase.
An allergy is defined as the overreaction of the human immune system to an otherwise harmless substance (“allergen”) such as pollen, peanuts, or cat hair. When an allergen is eaten, breathed into the lungs, injected, or touched, symptoms such as coughing, sneezing, itchy eyes, runny nose and scratchy throat can result. More severe cases can generate rashes, hives, lower blood pressure, difficulty breathing, asthma attacks, and even cause death.
An estimated 50 million Americans suffer from allergies, and approximately 55% of all U.S. citizens test positive to at least one type of allergen, including indoor and outdoor, food, drug, latex, insect, skin and eye allergens. The most common allergies are indoor and outdoor allergies, which include hay fever and seasonal or perennial allergies. Common triggers include tree, grass, and weed pollen; mold spores; dust mites; and pet dander. The most common food allergies (which are often labeled on packaged foods) are milk, soy, eggs, wheat, peanuts, tree nuts, fish and shellfish.
Allergy is the 5th leading chronic disease in the U.S. among all ages, and the 3rd most common chronic disease among children under 18 years old. The Asthma and Allergy Foundation of America says that “allergy prevalence overall has been increasing sine the early 1980s across all age, sex, and racial groups.” (AAFA.org) According to the National Institutes of Health (NIH), the prevalence of allergies in America has increased by two to five times, depending on the allergen. The number of children with food allergies rose by 18 percent from 1997 to 2007 (CDC.gov).
So, what’s causing this surge in allergies? There are several possibilities:
- One theory is the “hygiene hypothesis,” which suggests that because modern hygiene, sanitation, healthcare, etc. have all greatly improved as compared to previous times, our immune systems aren’t exposed to enough dirt, bacteria and other infectious agents, so our bodies overreact to benign substances like peanuts and pollen.
2. Another explanation is our increasing sensitivity to the abundance of synthetic chemicals and genetically engineered foods in the modern world. Genetically engineered food and ingredients do not require labeling in the U.S., and many possible allergenic chemicals go unlabeled as well, leaving consumers’ allergies untraceable.
3. Increases in allergies also have been attributed to climate change. Rising carbon dioxide levels in the atmosphere, warming global temperatures, and the resulting effects on seasons have been shown to cause higher rates of allergies in recent years. The Gallup-Healthways research group confirmed that high pollen counts in many areas across the country and the earlier arrival of allergens due to warmer winters have triggered higher rates of seasonal allergies this year than all previous years studied. Prolonged blooming seasons of plants such as ragweed and increased prevalence of mold due to changes in rain patterns also have been attributed to rising allergy rates. (Read more here.)
4, In addition, smog and other air pollution may contribute to increasing or worsening allergies.
There is no one explanation for the rise in allergies; it is likely a combination of these hypotheses. There is no cure for allergies, but they can be treated with medicine to alleviate symptoms or immunotherapy (allergy shots). The best treatment, though, is allergen avoidance and education.