Heat and heatwaves can affect our health and the health of people we care for in different ways.

You may be more at risk of heat-related health problems due to your age, existing medical conditions, where you live and work, and your economic and social status.

Some heat-related health problems can affect anyone, regardless of existing health status. These are often referred to as heat-related illness.​

How does heat affect the body?

When a person is exposed to heat, the body responds in ways to keep the body temperature from getting too high.

The body responds by increasing sweating to lose heat through evaporation of sweat on the skin and redistribution of blood towards the skin to be cooled.

Health problems can arise when:

  • the body’s response is unable to keep a person’s body temperature in the normal range
  • fluid lost through increased sweating is not adequately replaced 
  • the body’s response puts excessive strain on the heart.

Behaviours can contribute to effects that lead to heat-related health problems. For example:

  • Physical activity in high heat conditions can overwhelm the body’s mechanisms to regulate temperature.
  • Thick and heavy clothing can impair the cooling effect of sweat evaporation on the surface of the skin.
  • Not drinking enough water to replace fluid loss through sweat can lead to dehydration.

Babies and young children are limited in their ability to regulate body temperature. In those over the age of 65, age-related changes to the body can also increase the risk of heat-related health problems. ​

Learn the signs and symptoms of heat-related illness

It is important that we learn the signs, symptoms and first-aid for heat-related illness in ourselves and those we care for.

Look out for each other during hot weather

Before, during and after hot weather it is important to check on family and friends who may be more at risk, especially if they live alone.

  • Talk to your friends and family about ways that they can modify their homes to help with the hot summer ahead, such as installing blinds, air conditioning, or fans.
  • Before hot weather arrives, check that friends and family will be able to keep cool in their home. Check that they have enough food and medication so that they will not need to go out in the heat.
  • During periods of hot weather, check in with friends and family. If you cannot visit, check-in by phone.​
  • After a period of hot weather continue to check in on people at risk as the strain of heat exposure and disrupted sleep can affect people after the heat has passed.

Read more about how to plan ahead and beat the heat.​​​​​

Current as at: Monday 18 December 2023
Contact page owner: Environmental Health