08/25/2026
As global temperatures climb, a growing number of older adults are facing a point where their bodies simply can’t keep up, a state that physiologists call “uncompensable heat stress.” This is when sweating and other biological cooling mechanisms are overwhelmed and core body temperature keeps rising unchecked.
Previous projections have applied heat limits for healthy young adults to all age groups, overlooking the greater vulnerability in people 65 years and older. But with the world’s population aging rapidly – due to longer life expectancies and falling fertility rates – this could seriously underestimate future heat risks for elderly people.
A new study published in The Lancet Planetary Health by Stanford Health Policy (SHP) researchers Qinqin Kong, PhD, and Eran Bendavid, MD, MS, asks the question: if you factor in how age affects heat tolerance, how much does that change predictions of who’s at risk of heat-related illness and death?
A global analysis finds that aging populations may face intolerable heat more often, in more places, and for longer than previous estimates showed.