Yes, Climate Change Really is Making Your Hay Fever Worse

CThe change of Limate is bad news for many reasons – droughts, floods, heat, hurricanes. And then also, there is all sneeze. If you suffer from hay fever – or allergic rhinitis (AR) – and have found that your symptoms aggravate in recent years, you are not alone. Increasingly, health professionals conclude that as global heat also increases allergy symptoms.

In industrialized countries, hay cold diagnostics increases from 2% to 3% per year, which costs billions of dollars in health care and has lost productivity. The spring pollen season, which generally starts at the end of February or early March and ends at the start of the summer, is now up to 20 days earlier in North America. Now a new study in the journal The laryngoscope Has deeply plunged into research surrounding the link and noticed that not only is it a real phenomenon, but it has happened at least since the beginning of the millennium.

The study is called a review of the literature scope, that which takes the measure of the body of the articles published on a particular subject in a particular period of time and seeks to leave with an idea of ​​what the emerging consensus is on science. To do this, the authors of the current work sought to study all the available studies that addressed the link between climate change and allergies. More specifically, they zoom in to focus on published studies from 2000 to 2023 which explored the precise climatological mechanisms which would lead to global warming to exacerbate the symptoms of hay fever and which also measured how a warming world affects the length and severity of the hay fever season. Only 30 met these rigorous standards.

“We were very precise in our inclusion and exclusion criteria,” explains Alisha Pershad, a third -year student in medicine at the Georgeton University School of Medicine and Health Sciences, and the corresponding author of the new study. “By minimizing variability in our included studies, we were able to improve the strength of our conclusions.” These conclusions have revealed a lot.

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A little more than half of the studies that Pershad and his colleagues have examined have reported longer pollen seasons or higher pollen concentrations – or both – linked to climate change. One has planned that pollen emissions in the United States would increase by 16% to 40% at the turn of the century and that the average duration of the pollen season would increase by 19 days beyond the already observed increase by 20 days. Five of the studies have revealed that this extension will continue to occur at the start of the season. In Europe, projections have shown a likely increase in Ambrosia– or inch grass pollen – linked to the increase in temperatures.

Individual studies have deepened the link between climate and hay fever. A 2021 paper in Australia indicated that the maximum daily temperature, higher carbon dioxide concentrations in the atmosphere and the grass pollen index were all higher from 2016 to 2020 than they were from 1994 to 1999, pointing to a causal link going directly from CO2 to pollen. A European study of 2017 modeled increased growth in allergenic plants from 2041 to 2060 and predicted that the population of people allergic to lice grass would drop from 33 million to 77 million across the continent in this same window, while the coverage of plants would encroach to more and more communities.

Meanwhile, a study in 2025 from China revealed that ambulatory pediatric visits were up, in accordance with an increase in maximum pollen concentrations. As a 2025 study pointed out in the current document, children are “particularly vulnerable to these particles suspended in the air due to their higher ventilation per unit of body weight, more frequent oral breathing and outdoor activities.”

Find out more: Why the seasons of allergies worsen

The articles of the survey also examined the mechanism which links climate change to the increase in hay fever. A pair of nature and laboratory studies has shown that greater humidity and higher levels of carbon dioxide – which is known growth and a reproductive stimulator of plants – increases the dispersion of allergen pollen, while increased precipitation is effectively air, lowering pollen levels. Another study focused specifically on the mold allergen Aspergillus And noted that it is thriving under the current concentrations of carbon dioxide compared to the lower pre -industrial levels.

Not everyone does not suffer from current trends. As with so many other things, race, income, age and postal code play a role in the severity and epidemiology of hay symptoms, black and Hispanic communities, the elderly and low -income populations are less affected. The cities, with lower concentrations of trees, weeds and flower plants, are nevertheless associated with the worsening of hay symptoms, due to higher temperatures and the plate effect of concrete and asphalt, producing the phenomenon of urban heat island.

“Communities historically affected by environmental inequalities such as the red bond tend to live in regions that experience warmer diurnal temperatures,” explains Pershad. Allergen mold also discriminates demographically. “”[Mold] is particularly a concern for low -income communities which may not have the resources necessary to respond to water damage to their home as quickly as necessary to avoid growth of mold, “adds Pershad.” Global warming exacerbates weather conditions such as hurricanes and floods, which increases the risk of growth of mold, a common environmental allergen.“”