Do Probiotics Help With Seasonal Allergies?

Seasonal allergies—often called hay fever or allergic rhinitis—affect millions of people worldwide. Common triggers include pollen from trees, grasses, and weeds, which can cause sneezing, runny nose, watery eyes, and fatigue. While over-the-counter antihistamines remain the go-to solution for many, growing research suggests that probiotics may offer a natural way to help manage allergy symptoms.

But how exactly can gut bacteria influence seasonal allergies? And is there solid evidence to back it up? Let’s break it down.

The Gut–Immune System Connection

Up to 70% of the immune system resides in the gut, where it constantly interacts with the trillions of microbes that make up the gut microbiome. These bacteria help train immune cells to respond appropriately—attacking harmful pathogens but avoiding overreactions to harmless substances like pollen.

When the microbiome is out of balance (a state called dysbiosis), the immune system may become more prone to inflammation and hypersensitivity, increasing the risk of allergic reactions.

How Probiotics May Help With Allergies

1. Immune Modulation: Probiotics can influence T-helper cells—specifically by promoting a balance between Th1 and Th2 responses. Allergies are typically associated with an overactive Th2 response, and probiotics may help shift this toward a more balanced state.

2. Strengthening the Mucosal Barrier: A healthy gut lining prevents allergens and inflammatory molecules from leaking into the bloodstream, reducing overall immune activation.

3. Reducing Inflammation: Certain probiotic strains produce short-chain fatty acids (SCFAs) like butyrate, which have anti-inflammatory effects that may lessen allergy severity.

   
   
   
   

What the Research Says

A 2017 meta-analysis published in International Forum of Allergy & Rhinology reviewed 23 randomized controlled trials involving 1,919 participants and found that probiotic supplementation was associated with significant improvement in quality of life scores for seasonal allergy sufferers. However, results were not consistent across all studies, suggesting that benefits may depend heavily on the probiotic strain, dosage, and duration of use.

Another 2016 study in PLOS ONE focused on Lactobacillus gasseri and Bifidobacterium longum in people with Japanese cedar pollen allergy. Participants who took the probiotic mix for 8 weeks experienced reduced nasal symptoms and lower pollen-specific IgE antibody levels compared to the placebo group.

Best Probiotic Strains for Allergies

While more research is needed, the following strains have shown promise in clinical studies:

• Lactobacillus rhamnosus GG

• Lactobacillus paracasei LP-33

• Bifidobacterium longum BB536

• Lactobacillus gasseri TMC0356

Practical Tips for Using Probiotics for Seasonal Allergies

• Start Early: Begin supplementation 1–2 months before allergy season for best results.

• Choose Clinically Studied Strains: Not all probiotics help with allergies—strain specificity matters.

• Combine With a Healthy Diet: Prebiotic-rich foods (like garlic, onions, and oats) help feed beneficial bacteria.

• Consider Multi-Strain Formulas: A combination of strains may offer broader immune benefits.

Bottom Line

While probiotics aren’t a magic cure for seasonal allergies, there’s credible scientific evidence that certain strains may help reduce symptom severity and improve quality of life. If you struggle with allergies, adding the right probiotic to your routine—alongside other allergy management strategies—could be worth trying.