21. July 2020
Probiotics reduce hay fever symptoms

Probiotic food supplements can improve hay fever symptoms. This was revealed in a new study by the Allergy Centre Charité Berlin.

The study examined people suffering from birch pollen allergy. If they took a capsule with live probiotic bacteria for four months, their hay fever symptoms were reduced significantly. One outstanding aspect of the study is that it was conducted under strictly controlled conditions.



Allergen immunotherapy (AIT) is currently the only treatment that not only reduces symptoms over the short term but also treats the cause of allergies.

But there are other treatment strategies: We have known for at least ten years that certain bacterial strains can also alleviate allergy symptoms, such as those caused by a pollen allergy. However, the positive effects were revealed in low-quality studies, said ECARF expert Karl Bergmann at the 2020 European allergy congress, who claimed that it could not be clearly determined whether the variation in severity of the symptoms was due to varying pollen levels.

Bergmann and his team therefore tested all the participants under identical conditions in the ECARF pollen chamber.


Study procedure

Thirty participants with a confirmed birch pollen allergy were included in the study.  Furthermore, the study was conducted outside of the pollen season in order to exclude the possibility of airborne pollen affecting the severity of the symptoms.


The participants spent two hours inside the ECARF pollen chamber. During this period, they were exposed to exactly 8,000 birch pollen per cubic metre of air.

The temperature and the humidity inside the chamber were precisely regulated and kept the same for all participants. The patients reported whether they had any nose, eye or breathing symptoms every ten minutes. At the end of this period, everything was summarised in a total symptom score (TSS). All participants also underwent pulmonary function testing before and after spending time inside the chamber.


After the first test round inside the ECARF pollen chamber, the patients took a probiotic food supplement for four months. It contained Lactobacillus acidophilus (NCFM), Bifidobacterium lactis (BL-04) and oligofructose (FOS), a polysaccharide.


After the four-month period, 27 patients re-entered the pollen chamber and the test was repeated exactly as the first time.


The initial results show that all of them had significantly fewer symptoms. The results are statistically significant, which means that these results did not happen by chance but were directly linked to the treatment. However, the pulmonary function tests did not reveal any significant differences.

The probiotic food supplement therefore improved the symptoms significantly. It was also very well tolerated, said Bergmann.



Bergmann KL et al. Significant improvement of allergy symptoms after probiotic food supplementation measured in an allergen exposure chamber. EAACI 2020 poster session #1827