Young women sitting in dandelion field sneezing into a handkerchief, possibly due to an allergic reaction.

Not as trivial as one may think. How pollen allergy works and why you are absolutely right not to treat it lightly

If you do not have it, you likely know someone who has it or at least you have seen others suffering. In Germany, one in 5 of us are estimated to be suffering from hay fever, and the trend is increasing. The matter is unfortunately often trivialized and sufferers may not be given the proper attention in terms of treatment or preventive measures. 

In this article, we shed light on the complex bodily mechanisms that unfold when the body’s immune system is triggered by pollen and why it makes good sense to take this illness seriously rather than waive it off as “just” a pollen allergy and something to be endured.

Tiny pollen, big chain reaction. 

We don’t have an answer to why pollen - essentially microscopic plant reproductive  grains - in some of us can bring about a complex immune response.

Leaving aside that nature's ways are hidden from us, here's what happens when the airborne pollen released from weeds, grasses, trees and other plants finds its way into our eyes, and respiratory tract. 

The allergic reaction can be divided in two phases: sensitization and the allergic reaction with the symptoms we are familiar with. 

First phase: sensitization

During sensitization, many cells are involved and numerous molecules are secreted, such as the well-known cytokines.

The antigen, here pollen, will be taken up by a cell capable of absorbing and digesting it. Once done, it will present small pieces of proteins called peptides on its surface. It will present these peptides to naive T lymphocytes. This presentation will cause the naive T lymphocytes to activate and produce numerous cytokines. These cytokines will in turn activate B lymphocytes, which will produce type E Immunoglobulins specific to the pollen. The immunoglobulins will then bind to mast cells containing the famous histamine. Mast cells are found throughout the body's tissues, especially near external surfaces such as the skin, lungs, nose, and digestive tract. Covered with immunoglobulin, the mast cells are now ready for the allergic reaction, a ticking time bomb. But so far, so good, no symptoms on the horizon.

Stage 2: the allergic reaction

  1. The allergic reaction only occurs upon a second encounter with the allergen. As seen previously our mast cells are covered with immunoglobulin, waiting for just one thing: to come into contact with the allergen. However, contact with just one immunoglobulin is not enough. There must be contact with two immunoglobulins, a bridge must be done. If this contact occurs, then the signal is given. The mast cell will then degranulate and release the infamous histamine.
  2. Histamine and other released inflammatory mediators then cause swelling, secretion, itching or narrowing of airways - hence the runny nose, itchy eyes and sneezing when experiencing a hay fever attack. In severe cases can bring on asthmatic attacks as the airways of the lungs constrict.

From Emilio Nuñez-Borque et al, Pathophysiological, Cellular, and Molecular Events of the Vascular System in Anaphylaxis, Front Immunol. 2022 Mar 8:13:836222. doi: 10.3389/fimmu.2022.836222.

Why do some people get it while others do not? 

The answer is: we do not really know, and influencing factors are various. Gender might partially influence the likelihood of developing pollen allergy as might age: while it is more common in boys, upon reaching adulthood more women than men seem to be affected by it. There is some indication that a higher birth order, and to a lesser extent the number of siblings, is associated with a lower risk of developing pollen allergy. 

Genetics and epigenetics are certainly part of the reason, specific genes seem to be linked to the development of the condition. Plus there is data supporting climate change and environmental factors impacting the globally increasing numbers of sufferers.

“I never had anything -  until this year. Could it be that I developed a pollen allergy?”

Stories are numerous, from young adults to older generations: a sudden change of location might result in the first experience of a hay fever attack, be it when moving to a different country or going to a foreign destination for a vacation. You likely never felt anything all your life, then suddenly it hits you. What we struggle to understand is when and where that first (or repeated) exposure occurred that triggered the initial development of IgE antibodies.

Seasonal horror and beyond 

What unfolds next is the repeated experience of suffering whenever the pollen count of the pollen you are allergic to is high and you happen to be outside. Maybe it is the fact that so many people go through it, maybe the reason is that it is “seasonal” and to a certain extent to be expected that leads to a common understanding of pollen allergy as not being an illness. Personally, I am reminded of the stigma around menopause or menstruation. 50 % of the global population are affected on a rather regular and to a certain extent, calculable, expected basis. Even if the individual suffering might vary between women, some suffering more, some suffering less, the mechanism in place is quite similar to pollen allergy sufferers: there is an expectation from society & ourselves, that our bodies function regardless of the day, month, season.

And there is still a long way to go for a common understanding that this, too, comes with an effect on the workforce, not to speak of the mental load that women in this case carry to function & perform while their bodies put quite radical, physical limits to what is naturally possible. Here too, advocacy and empathy is needed to come up with creative and complementary solutions to support women in their journey and help them materialize their desires & needs. 

For pollen allergy sufferers, the consequences of not taking their allergies seriously might go beyond a psychological effect: if left untreated, hay fever can extend to the lower respiratory tract. This consequence occurs in 30 to 40 percent of allergy sufferers, leading to inflamed bronchi and even to the development of allergic asthma. A normally temporarily limited condition then becomes a chronic illness. 

Hence the reason for this article, we want everyone to take this matter seriously. And there are endless resources available on the web to consult what might make sense as treatment options. In that jungle of information we specifically want to highlight the importance of the very first step: identifying which types of plant pollen(s) are your personal culprit. Knowing what to avoid is key to managing your allergies. To the extent that some people take “pollen vacation” scheduled around the time of their personal pollen season. Of course, these radical solutions are not always possible and need not be necessary for you. By trial and error, finding out what pharmaceutical, nutritional and lifestyle solution strategies work best for you personally in YOUR allergy management, will get you a long way. 

Complement this article with our other article on treatment options, consult your healthcare professional for help and subscribe to our newsletter if you would like to stay informed. Do you have comments or questions? Write us an email. We are always keen to hear about the person behind the pollen allergy experience.


Allergic Rhinitis: 

This is a medical term used to describe symptoms that occur when someone is allergic to an airborne substance, such as pollen, dust, mold, or pet dander. Allergic rhinitis can be either seasonal or perennial. Seasonal allergic rhinitis is caused by outdoor allergens like tree, grass, or weed pollen, and typically occurs during specific times of the year when these plants are in bloom. Perennial allergic rhinitis, on the other hand, occurs year-round and is usually triggered by indoor allergens like dust mites, pet dander, or mold.

Hay Fever: 

Hay fever is a common name for seasonal allergic rhinitis, especially when it's caused by pollen from grasses, trees, and weeds. The term "hay fever" historically comes from reactions people would have during the hay harvesting season, though the symptoms are not caused by hay, nor do they include fever, although from a sufferers‘ perspective it may feel like a feverish state sometimes. Hay fever is a more specific term for pollen allergies compared to allergic rhinitis and typically refers to the allergic responses occurring during specific seasons due to pollen.