More than 2,700 people may have died from heat-related causes during recent heatwaves in England and Wales, according to researchers tracking the health impact of extreme temperatures.
The estimate points to the growing toll of prolonged hot weather on public health, especially among older adults, people with existing medical conditions and those living in homes or care settings that can become dangerously warm. Experts say heat can worsen heart and lung disease, increase dehydration and place added strain on the body, raising the risk of serious illness and death.
The findings are based on analysis of excess deaths recorded during periods of unusually high temperatures. Excess death studies compare the number of deaths observed during a specific period with the number that would normally be expected. Researchers use that method to estimate how many deaths may be linked, directly or indirectly, to extreme heat.
Health specialists have long warned that heatwaves are not only uncomfortable but can also become a major public health emergency. Unlike storms or floods, the danger often builds quietly. Many deaths linked to high temperatures are not immediately identified as heat-related, because heat may aggravate existing illnesses rather than appear as the sole cause.
Older people are typically considered the most vulnerable, partly because the body becomes less effective at regulating temperature with age. People with chronic conditions, including cardiovascular and respiratory disease, are also at higher risk. Infants, outdoor workers and those who are socially isolated or unable to keep their homes cool can also face elevated danger during sustained hot weather.
Public health guidance during heatwaves usually urges people to drink enough fluids, avoid strenuous activity during the hottest parts of the day, keep living spaces as cool as possible and check on relatives, neighbors and others who may need help. Officials also advise care providers and hospitals to take extra precautions when temperatures rise for several days.
The latest estimate is likely to add to concerns that climate change is increasing the frequency, intensity and duration of extreme heat events in the UK. Scientists have repeatedly said that higher average global temperatures make severe heat more likely, even in countries that have historically experienced milder summers.
Researchers say the figures underline the need for better heat preparedness, including clearer warnings, housing that is more resilient to high temperatures and stronger protections for vulnerable groups. While cold weather has often received more attention in the UK, health experts argue that heat should now be treated as a similarly serious and recurring threat.
Why the numbers matter
The estimate does not mean every death occurred solely because of heat, but it suggests extreme temperatures played a significant role in pushing mortality higher than normal. For health officials, that makes heatwaves an increasingly important measure of national resilience as summers become hotter and public services face mounting pressure.
Key questions
- What are heat-related deaths?
- Heat-related deaths are fatalities in which high temperatures contribute to worsening health conditions such as heart disease, lung disease or dehydration, even if heat is not listed as the only cause.
- Who is most at risk during a heatwave?
- Older adults, people with chronic medical conditions, infants, outdoor workers and those living in poorly ventilated or overheated homes are among the groups most vulnerable during extreme heat.
