Hot weather during the summer can affect anyone, but some people run a greater risk of serious harm.
Experts recommend checking on those who may be more vulnerable, such as older people and babies.
As the body gets hotter, blood vessels open up. This leads to lower blood pressure and makes the heart work harder to push the blood around the body.
This process can cause mild symptoms such as an itchy heat rash or swollen feet.
At the same time, sweating leads to the loss of fluids and salt and, crucially, the balance between them in the body changes.
