Health effects of heat

Dr Tendai Zuze
Health Matters
AS we move deeper into summer in Zimbabwe, temperatures are getting higher, and many parts of the country are already experiencing heatwaves.
While most people feel uncomfortable in hot weather, heat can be dangerous—especially for those with chronic health problems such as heart disease, diabetes, high blood pressure, or asthma.
When it is very hot, the body tries to cool itself by sweating and sending more blood to the skin.
This can cause dehydration and put extra strain on the heart and kidneys. People with heart disease may feel weak, dizzy, or short of breath.
Those with diabetes can experience high blood sugar levels because dehydration affects how insulin works.
Some medicines, like diuretics or certain diabetic drugs, can also make the body lose more water and salt, increasing the risk of dehydration.
Heat can make breathing problems worse too.
People with asthma or chronic lung disease may find it harder to breathe as hot air and dust irritate their airways.
The elderly and young children are at special risk because they cannot cool down as easily and may not realise when they are overheating.
Besides affecting chronic illnesses, high temperatures can also cause other health problems.
Heat exhaustion and heat stroke can occur when the body’s temperature rises too high.
Symptoms include headache, confusion, nausea, and sometimes fainting.
Prolonged heat can lead to swelling of the feet, rashes, and worsening of skin conditions. It can also increase the risk of food poisoning, as food spoils faster in the heat.
To stay safe, it is important to drink plenty of water, stay in cool or shaded places, wear light clothing, and avoid being outdoors during the hottest parts of the day.
People with chronic conditions should continue taking their medicines, but check with their doctor if they feel unwell, as some medicines may need adjustment during very hot weather.
As Zimbabwe’s summer temperatures rise, heat safety should be taken seriously.
Staying hydrated, keeping cool, and looking out for those most at risk, especially the elderly and those with chronic illnesses, can help prevent illness and save lives.
With many outdoor events now taking place across Zimbabwe, such as cancer awareness walks, fundraising marathons, and sports tournaments, it’s important to take steps to reduce the harmful effects of heat.
Participants should drink water frequently before, during, and after events, wear light and breathable clothing, use sunscreen, and rest often in shaded or cool areas.
Event organisers should plan for early morning or late afternoon start times, provide water stations, first aid support, and ensure there are shaded rest points along the route.
For cancer survivors and patients taking part in awareness events, the precautions are even more important. Some cancer treatments, such as chemotherapy and radiotherapy, make the skin more sensitive to sunlight and can increase fatigue or dehydration risk. Wearing wide-brimmed hats, using sunscreen, and avoiding long exposure to direct sun can prevent complications.
As temperatures continue to rise this summer, protecting ourselves from heat is essential. Staying hydrated, dressing appropriately, planning outdoor activities wisely, and looking out for vulnerable people can make the difference between a safe, enjoyable season and a medical emergency.
Heat safety should now be a routine part of every community, sporting, and health awareness event across the country.

For more on the health effects of heat, contact [email protected]