What is


Hay fever has a strange name. It’s an allergy to grass, not hay, and it doesn’t produce a fever. Pollen is the male fertilizing agent of flowering plants, trees, grasses and weeds1. Our environment needs it, but it is also responsible for hay fever which affects between 10% and 30% of the population2.

How does pollen affect allergies,
hay fever and asthma?

Hay fever and allergies

Hay fever is an allergic reaction to pollen, typically when it comes into contact with your mouth, nose, eyes and throat3. Also known as seasonal rhinitis, it is caused by the immune system releasing histamine as well as other chemicals into the body to fight off the allergens. Symptoms include itchy/watery eyes, wheezing, headaches and blocked sinuses.


Because there are many different types of pollen including grass pollen, tree pollen, flower pollen, it is important to find out which one you are allergic to.

Hay fever affects 10-30% of all adults and as many as 40% of children4.


Asthma is a complex condition which experts say, intermittently inflames and narrows the airways in the lungs. This inflammation makes the airways swell; causing periods of wheezing, chest tightness, shortness of breath, and coughing. It affects people of all ages and those who are diagnosed experience symptoms ranging from mild to severe5.



Substances, including pollen, that cause allergies can trigger asthma. If you inhale something you are allergic to, you may have asthma symptoms. This is called allergic asthma according to the Asthma and Allergy Foundation of America and it is something that is on the rise6.


A study found a 54% increased chance of asthma attacks7 when exposed to pollen.

Where does pollen come from?

Each minuscule pollen grain is transported by various means (wind, water, insects, etc.) to the female structures, where fertilization occurs. This means that pollen levels vary from place to place. 

To find the pollen levels in your area then, there are three things to think about:


1. Your location

As we can be allergic to almost any type of male pollen, it depends on which tree, grass or weed is fertilising at the time.


2. Pollen season

Similarly, tree, grass or weed pollen can depend on where you are from. Ragweed and Elm trees are common across most of North America, whereas Mountain Cedar is more common in Arkansas, Missouri, Oklahoma, and Texas8. You therefore need to know the pollen season in your local area.


3. Your specific allergy

Ask your healthcare professional about blood tests for pollen. This could help you find out exactly what you are allergic to!

A single birch tree can produce up to 5 million pollen grains10, and research has shown that it can travel up to 10 miles from the parent tree11.

Increased pollen levels due to global warming

As we all know, human actions on this planet can have adverse effects on our planet and it’s many, intricate ecosystems. A harvard study found that since 1990, pollen seasons have gotten longer and more pollen filled as a result of climate change. The increased temperature extends the duration of the pollen season, causing problems for asthma sufferers and ecosystems alike.


Similarly, city planners have been warned about the unintentional effects we can have on pollen levels. It is reported that male trees are often favoured by urban landscape planners as female trees can shed fruit as well as seeds and pods. This is something that would never occur in nature. “Pollen producing trees that are dioecious (with male and female flowers on separate plants) are seen to add to the effect of allergies of city dwellers.”


We take this seriously, learn more about Airthings sustainability goals.

Tips to help hay fever?

With My Pollen Levels, you know exactly when you need to take action against pollen, as you can check when it is high in your area. Having allergies doesn’t have to be a huge burden! Here are a few tips to help your everyday life whilst suffering from hayfever.

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Wash off any pollen

After a day outside in high pollen season, showering, washing your hair and changing your clothing once you arrive home can help. This is because it can reduce the amount of pollen you carry with you indoors.

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Try a vaseline barrier

Vaseline or a petroleum jelly substitute is a simple, affordable household product that can help reduce hay fever symptoms. Applying a small amount around the nostrils will help trap pollen before it enters the body and cause an allergic reaction.

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Avoid fresh flowers indoors

Keeping fresh cut flowers indoors may be beautiful, but they too can release pollen.

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Know when to close your windows

It may sound counter intuitive to ‘fresh air’, but it can often help allergy sufferers to close windows and doors when pollen levels are high. This stops the pollen coming inside and irritating you further.

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Keep clean and tidy

Vacuuming regularly and wiping down surfaces with damp cloths will reduce the amount of pollen able to get into your home. Regularly washing your hands can also be of great benefit.

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Stop cutting the grass

You now have the perfect excuse for a friend or relative to help with cutting your lawn. Those with grass allergies should avoid cutting the grass where possible, as this can exacerbate their symptoms.


No smoking

Not only is smoking bad for your health as a carcinogenic, the NHS recommend that you do not smoke if you have allergies, as it makes your symptoms worse15.

What do my Pollen levels mean?


Low pollen levels. Breathe easy. My Pollen App provides forecasts so you can be prepared for higher levels.


Fair pollen levels. Start to get into the routine of changing your clothes once you home to wash off any pollen. Keep an eye on your pollen count in your area.


High pollen levels. Try reducing your pollen exposure indoors by closing the windows, replacing air conditioning filters and following our top tips!