Most of us welcome hot weather, but when it's too hot for too long, there are health risks.
Sunlight shining through hand.
Why is a heatwave a problem?
The main risks posed by a heatwave are:
- not having enough water (dehydration)
- overheating, which can make symptoms worse for people who already have problems with their heart or breathing
- heat exhaustion and heatstroke
Who's most at risk?
A heatwave can affect anyone, but the most vulnerable people are:
- older people, especially those over 75
- babies and young children
- people with a serious long-term condition, especially heart or breathing problems
- people with mobility problems – for example, people with Parkinson's disease or who have had a stroke
- people with serious mental health problems
- people on certain medicines, including those that affect sweating and temperature control
- people who misuse alcohol or drugs
- people who are physically active – for example, labourers or those doing sports
Read more about heatwave alert levels on NHS.uk and about how the current COVID-19 pandemic will amplify the health risks from heat on PHE.uk.