Is Pollen Season Growing Longer? A Study Investigates
Is Pollen Season Growing Longer? A Study Investigates
by Nextmune on March 12, 2021 at 10:46 PM

Does pollen season bring in more and more allergy patients each year? Based on a new study from The Lancet Public Health, this could be true.

During the study, researchers reviewed two decades of airborne pollen and temperature data in 17 different locations throughout the northern hemisphere. They found that a majority of the locations showed a higher concentration of allergenic pollen produced annually than was observed 20 years ago. They also discovered over 60% of the regions displayed a significantly longer pollen season duration.

What’s causing longer pollen seasons?

The study authors theorized that seasonal changes and a decrease in the number of ‘frost-free’ days could have contributed. The study states: “The  lengthening of pollen seasons is related both to earlier springs (ie, last spring frost occurring earlier) as well as later autumns  (delay in the occurrence of the first autumn frost).” This makes sense as plants tend to grow better in warmer weather.

What’s causing the higher pollen concentrations?

Study author, Lewis H Ziska, Ph.D., proposed an explanation in an interview with MD Magazine. He said as temperatures and the amount of carbon dioxide in the air both increase, so does plant growth. Plants use that carbon dioxide as food – especially weeds, which tend to produce more pollen. In an interview with, he points out how when there’s too much carbon dioxide, weeds can grow faster than other plants (like crops).

What does this mean for you and your practice?

Dr. Ziska and his team predict that these findings may lead to eventual health implications – especially for allergy-sufferers. The study states: "Future climate projections also suggest ... an estimated doubling in sensitization to allergenic plants such as ragweed." What does this mean? For some, it could indicate more reactivity to specific allergens and for others, more severe reactions.

These symptoms are not mutually exclusive to humans – they apply to animals as well. That makes allergy testing and immunotherapy all the more important to keep in mind when evaluating suspected allergy cases in your practice. Nextmune’s comprehensive panel tests for allergies to the most common weeds, trees and grasses. 

We also provide immunotherapy/hyposensitization treatment for those allergens. Keep in mind – the faster they get started on treatment, the easier it is for their immune system to adapt and get those symptoms under control.