Study Finds Elderly Population Far More Vulnerable to Extreme Heat Than Previously Thought

A study published in The Lancet Public Health reveals that people aged 60 and over face dangerous health risks from extreme heat at much lower temperatures than previously estimated. The research, led by health academics from Stanford University, indicates that older adults are more susceptible to uncompensable heat stress, a condition where the body loses its ability to cool itself. This vulnerability is attributed to physiological factors such as decreased sweating, weaker heart function, and blood vessels that are less able to widen. Previous research often overlooked these risks by applying heat balance thresholds based on younger populations to all age groups.

The study warns that as global temperatures rise, a growing number of people will suffer from heat stress. At 1.5 degrees Celsius of warming above preindustrial levels, 22 percent of people over 60 will already be at risk. In India, over 80 percent of the elderly could face dangerous heat levels if global warming reaches 3 degrees Celsius. The burden is expected to increase as the global population of people aged 60 and over is projected to double to 2.1 billion by 2050, with particularly severe impacts in low and middle income countries like India and Pakistan.

Experts note that each additional degree of global heating exposes roughly one million more people to at least 180 hours of uncompensable heat stress annually. Some authors of the study suggest that parts of the tropics and subtropics could eventually become uninhabitable, especially for older populations. In the United Kingdom, the Health Security Agency has expressed concern that rising temperatures could lead to record heat related deaths, noting that heatwaves in May and June of 2026 caused 2,877 excess deaths.