New Issue: Science’s Impossible Questions. Read Now

Global Study Links Climate to Rates of Childhood Asthma

Join Our Community of Science Lovers!


On supporting science journalism

If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.


A city's climate can influence more than just how comfortable its inhabitants will be, a new study suggests. A report published in the July issue of the journal Occupational and Environmental Medicine indicates that meteorological variables such as temperature and humidity are linked to rates of childhood asthma and eczema.

Stephan K. Weiland of the University of Ulm in Germany and his colleagues analyzed data collected from more than 650,000 subjects as part of the International Study of Asthma and Allergies in Childhood, which includes 155 participating centers around the world. The team compared the incidence of asthma and eczema to climate data for two groups: children between the ages of six and seven and youngsters aged 12 to 13. According to the report, for countries in western Europe each 10 percent increase in indoor humidity was linked to an almost 3 percent rise in the reported rate of asthma. What is more, cities in which the average humidity dropped below 50 percent for at least one month a year had lower rates of asthma compared to more humid locales. Higher altitude destinations and those with more variable temperatures were associated with lower asthma rates, whereas children living in cities with higher temperatures were less likely to have eczema.

Just how humidity affects asthma rates remains unclear, the authors caution, although increased exposure to dust mites and higher amounts of mold could be factors. The team notes that its study is the first to take a global view to examine the relationship between asthma and eczema and climate. The results, the authors conclude, ¿may also have implications for the assessment of potential health effects due to climate change.¿

Subscribe to Support Independent Journalism

Great science journalism requires human expertise, time, effort and creativity. And it costs money. That’s why I and the journalists here at Scientific American hope you’ll join our community.

When you subscribe, you are supporting staff and freelance journalists who are passionate about telling science stories that are true, important and compelling. Our editors and reporters are often experts in their fields, which means they understand the nuances of big discoveries and can untangle the breakthroughs from the hype. With a subscription, you are also supporting rigorous fact-checking to ensure the words we publish are precise and accurate. And you’re supporting original illustrations, graphics and photos that bring you closer to an advanced laboratory, an ice sheet in Antarctica or a space mission in orbit. You’re helping us craft other types of high-quality journalism as well: Our newsletters are carefully written, edited and curated by staffers you have or will come to know and love. Our Science Quickly podcast is based on original reporting, collaboration with editors and scientists and exacting production.

Subscriptions keep this engine running so we can continue to deliver thoughtful, rigorous and independent science journalism to you. In an era of viral misinformation, this work is crucial. If you value what we do, I hope you’ll consider joining us as a subscriber

Thank you,

Jeanna Bryner, Editor in Chief, Scientific American

Subscribe