Seasonal allergies could, in fact, be a sign that the body is doing what it is supposed to do; that your immune system is protecting you from environmental toxins, which damage your health much more than pollen or other allergens, researchers from Yale School of Medicine andthe Howard Hughes Medical Institute reported in Nature. So, if you find yourself coughing, sneezing and complaining about smarting eyes, remember that your body’s hypersensitivity may be doing what it is meant to do.
The human body’s defense system includes various responses which deal with a range of pathogens (things that harm us).
Type 1 immunity relies mainly on directly destroying infected host cells or pathogens.
The article concentrates on Type 2 Immunity. This type protects the body from environmental substances by activating the body’s T-cells, as well as antibodies to attack the irritant.
However, sometimes Type 2 Immunity can overreact when triggered by antigens in the environment, such as pollens. Antigens are substances or things which trigger an immune response in some people, but they are not pathogens. In hay fever sufferers, for example, pollen makes the body produce too much histamine, which leads to a runny nose, coughing, sneezing, itchy eyes, and all the unpleasant symptoms which prevail from spring, to summer, and right into autumn for some people.
Hay fever may have positive value for humans
Even so, the authors argue that Type 2 Immunity is good for humans, in spite of the occasional misfiring. This type of defense system developed over thousands of years to protect our bodies from at least four different types of environmental challenges:
- Environmental irritants
- Harmful chemicals
- Parasites (helminthes)
- Venom from animals
However, if Type 2 Immunity evolved over thousands of years to protect our bodies, why sense such tiny amounts of allergen when their levels are completely harmless? Why all the suffering if there seems to be no evolutionary point to it?
Lead author Ruslan Medzhitov, said:
“We believe that allergic hypersensitivity evolved to survey the environment for the presence of noxious substances.
After the first exposure, the immune system gains a memory, and subsequent exposure to even minute amounts will induce an anticipatory response that helps minimize potentially harmful effects.”
He explained that overactive Type 2 Immunity makes the person avoid environments that contain harmful substances.
Medzhitov said:
“According to this view, hypersensitivity to allergens triggers avoidance of a sub-optimal environment.”
Written by Christian Nordqvist