Heat and humidity could push stunting higher in South Asia by 2050
Heat and humidity could push stunting higher in South Asia by 2050
New study links extreme heat and humidity from climate change to rising stunting in South Asia, highlighting pregnancy risks and welfare implications.
Heat and humidity driven by climate change could raise the number of stunted children in South Asia by more than three million by 2050, according to a new study. Researchers from the University of California, Santa Barbara analyzed 'height-for-age' as a health indicator for children under five, focusing on exposure to extremely hot, humid conditions during pregnancy. They found that humidity compounds heat stress, making cooling more difficult for pregnant women, with the worst effects in the early and late stages of pregnancy. In particular, heat and humidity during the third trimester were about four times more damaging than heat alone, according to the study.
The concept of wet-bulb globe temperature, which accounts for humidity, radiant heat and airflow, proved crucial. Each extra day when maximum WBGT exceeded 29C correlated with fewer live births six to 12 months later, while days above 35C were linked to more pronounced negative health outcomes for newborns.
Policy implications: The findings suggest that simply tracking air temperature underestimates climate risks to child health. Public health officials should integrate humidity and heat into heat-warning systems, prenatal care guidelines, and nutrition programs, especially in climate-vulnerable districts of India and neighboring countries. The research underscores the need for climate adaptation that protects pregnant women and young children, including better cooling strategies, access to healthcare, and social support during heatwaves.
As heat events intensify across the region, the study warns that millions of children could bear the long-term consequences of a warming, humid climate.
