Birch pollen allergy
Sneezing and streaming eyes every April, and maybe a tingle in your mouth when you bite an apple? Birch is one of the most common tree pollen triggers in northern and central Europe. Our test checks your blood for IgE sensitisation to three birch pollen proteins, as part of 300 allergens and allergen components, so you see whether birch shows up and what sits next to it.
- Group
- Pollen
- Season
- Roughly late March to May in central Europe, peaking in April; earlier in warm years
- Also known as
- birch allergy, silver birch, Betula, Bet v 1, tree pollen
Where you meet it
- Parks, gardens, streets and woodland planted with birch
- Outdoors on dry, windy days in spring, when pollen counts peak
- Indoors on clothes, hair and open windows after a day outside
- Some raw fruits, nuts and vegetables that share similar proteins (see cross-reactions)
What birch pollen is
Birch trees release huge amounts of light pollen that travels far on the wind. You do not need a birch in your garden to meet it; a few streets away is enough.
The main protein people react to is called Bet v 1. It belongs to a family of plant proteins (PR-10) that also appears in many fruits, nuts and vegetables. That shared family is why birch rarely travels alone.
What people commonly report
The classic pattern is hay fever in spring: sneezing, a runny or blocked nose, and itchy, watery eyes. Some people notice a scratchy throat or a cough on high-pollen days.
Symptoms often track the weather. Dry, warm, windy days tend to be worse; rain usually brings a short break.
- Sneezing in bursts, especially outdoors
- Itchy, red or watery eyes
- Runny or blocked nose
- Itching in the mouth or throat after some raw fruit
Birch and food: the apple connection
Because Bet v 1 looks similar to proteins in some foods, many people sensitised to birch notice itching or tingling in the lips, mouth or throat after eating them raw. This is often called oral allergy syndrome or pollen-food syndrome.
Common examples are apple, hazelnut, stone fruits such as cherry, peach and plum, carrot and celery. These PR-10 proteins are usually broken down by cooking, which is why baked apple is often tolerated when raw apple is not. That is a general pattern, not a rule for you; reactions vary, and celery in particular can behave differently.
How the test checks birch
From a finger-prick sample, the lab measures IgE antibodies against three single birch pollen proteins (molecular components) as part of 300 allergens and allergen components. The same report shows alder, a related tree, and foods linked to birch through similar proteins, such as hazelnut (Cor a 1), apple (Mal d 1) and soy (Gly m 4). Hazel pollen is not measured separately.
A positive result means your immune system has made IgE to birch. That is sensitisation, not proof of a clinical allergy. Plenty of people are sensitised without symptoms. Your lab report gives each value a class from Negative to Very high, a starting point for a conversation with a doctor, not instructions.
- Bet v 1: the main birch pollen protein (PR-10 family)
- Bet v 6: a minor birch protein (isoflavone reductase)
- Bet v 7: a minor birch protein (cyclophilin)
Known cross-reactions
- Alder pollen
- Alder and birch are close relatives. Alder's Aln g 1 resembles birch's Bet v 1, so many people sensitised to one are sensitised to the other; alder simply flowers earlier.
- Hazelnut
- A common birch-related food. The raw nut can cause mouth itching in people sensitised to birch.
- Apple
- The textbook birch-associated fruit. Reactions are usually limited to the mouth and often fade when the apple is cooked.
- Stone fruits, carrot and celery
- Cherry, peach, plum, raw carrot and celery contain related proteins and are frequently reported alongside birch sensitisation.
- Hazel pollen
- Another birch-family tree with a similar PR-10 protein. The panel has no separate hazel pollen marker; birch and alder results are the closest guide.
300 allergens. One test.
A finger-prick sample at home, sent by post. A detailed lab report typically 5 days after the lab receives your sample, and our plain-English guide to reading it. €300, €1 per allergen.
Questions
When is birch pollen season?
In central Europe birch usually flowers from late March to May, with the peak in April. Warm springs can shift it a couple of weeks earlier. Hazel and alder come before it, grasses after it.
Why does my mouth itch when I eat an apple?
Apple contains a protein that resembles the main birch pollen protein, Bet v 1. If you are sensitised to birch, your immune system may react to the apple version too, usually with itching in the lips, mouth or throat. If you notice swelling or any trouble breathing, see a doctor.
Does a positive birch result mean I am allergic to birch?
No. It means your blood contains IgE to birch pollen, which is called sensitisation. Whether that causes symptoms is a clinical question. A doctor puts your result together with what you actually experience.
Can I test for birch outside of pollen season?
Yes. IgE antibodies are measurable all year, so you can test in winter and have your results before the season starts.