Author: Ashley Johnson, Allergychoices
Allergies are on the rise! According to the Centers for Disease Control and Prevention, from 1997 to 2011, food and skin allergies increased in children under the age of 18. In addition, inhalant and environmental allergen complaints grow among the general population. There are many theories as to why allergic disease is increasing including the hygiene hypothesis, as well as longer allergy seasons due to global climate change.
The most supported theory behind the increase of allergies is the hygiene hypothesis. The AAAAI (American Academy of Allergy Asthma & Immunology) states that the hygiene hypotheses, “…suggests that living conditions in much of the world might be too clean and that kids aren’t being exposed to germs that train their immune systems to tell the difference between harmless and harmful irritants.”
The theory was first introduced in the late 1980s by David P. Strachan, a professor of epidemiology. Today the theory is supported by several studies that show that in developed countries where there is better sanitation, water supplies, and children with fewer infections, there is a significant increase in allergy compared to populations in less developed areas.
Increased exposures to endotoxins, a poisonous substance present in certain bacteria that stimulate and “educate” the immune system, decreases allergic inflammation. In accordance with the Food and Drug Administration (FDA), the hygiene hypothesis suggests that the immune system must be educated to properly function so it can learn to defend against infectious organisms.
There is still more research to be done regarding different lifestyles in developed and underdeveloped countries that lead to protection against the development of allergies, as well as an expansion of current research looking at ways to prevent the development of allergies.
Global climate change
Though sometimes a controversial issue, global climate change is also thought to be, in part, responsible for an increase in allergies, making the matter not only an environmental issue but also a health issue. The National Wildlife Federation says that due to climate change, environmental allergies will worsen for approximately 25 million Americans. This is due to allergen triggers such as ragweed that grows faster and produces more pollen under increased carbon dioxide levels. In addition, warmer conditions lead to expansions of allergenic trees, and also increase the amount of fungal antigens in the air. This theory was supported by data from pollen count trends collected by the National Allergy Bureau pollen stations (one of which is located at Allergy Associates of La Crosse in Onalaska, WI).
Other effects of climate change include the increase of allergic asthma attacks due to the exacerbation of air pollution and pollen production in cities that leads to the “Urban Heat Island Effect.” As a result of these environmental changes the American College of Allergy, Asthma & Immunology says “…hay fever or seasonal allergic rhinitis lasts up to three weeks longer than it used to, and the further north you live, the longer you have to wait for relief.”
Researchers note that changes in reporting of allergic conditions may also be a factor in increased reporting of allergies, but seem to concur that more people are seeing stronger reactions to substances that normally should not cause problems. Changes in the global diet and gut bacteria are also considered to be potential influencing factors.
More people suffering from allergy
The key takeaway is that more people are suffering from allergy, and the impact is being felt through the growing number of related health issues and healthcare costs.
The outdated solution to try to avoid allergens is increasingly difficult, and unnecessary. Lifestyle and dietary modifications are great first steps. Immunotherapy, notably custom sublingual immunotherapy that addresses specific allergic issues, is becoming one of the most accessible and affordable ways to retrain the body to tolerate problem allergens long term. As more people suffer from allergy, helping them access disease modifying treatment like sublingual immunotherapy has never been more necessary.