For many of us the prospect of a hot and sunshine-filled weekend brings joyful anticipation. However, in light of the heat-health alert recently issued by the UK Health Security Agency let’s put our sensible heads on and take a few moments to acknowledge the importance of staying safe as the temperature rises.
Why is extreme heat a health risk?
Regardless of how extremely hot (or cold) the environmental temperature may be, our bodies constantly work to keep our core temperature at 37°C. As the external temperature rises the more bodily processes have to be ramped up in order to keep cool. In hot weather the body cools itself primarily by sweating. When sweat evaporates heat loss from the skin increases. The downside of this is the corresponding loss of fluids and salt. In addition, the blood vessels near the surface of the skin dilate in order to allow more heat to be lost, leading to lower blood pressure. This means that the heart has to work much harder to keep blood pumping around the body. This combined with excess sweating can lead to heat exhaustion
What are the symptoms of heat exhaustion?
The symptoms of heat exhaustion are:
- Nausea
- Headaches
- Dizziness
- Fainting
- Confusion
- Muscle cramps
- Swelling in the ankles and lower limbs
- Lethargy
Untreated heat exhaustion can lead to heat stroke. If you experience heat exhaustion, stop all activity and move to a cool location. Drink cool water or ionic sports drinks.
What is heat stroke?
Heat stroke is the most serious heat related condition. It occurs when the body can no longer control core temperature and it rises to 40°C or higher. The symptoms of heat stroke are:
- A core body temperature of 40°C or higher
- Confusion, agitation or slurred speech
- Nausea or vomiting
- Rapid breathing
- Racing heart rate
- Throbbing headache
If you suspect that someone may be suffering from heat stroke seek urgent medical attention.
Who is most at risk from heat?
Some people are more at risk from the heat. These are:
- Older people, especially over 75 years of age.
- Children, especially under 4 years of age.
- People with health issues, particularly heart or respiratory conditions.
- People who live alone or are socially isolated.
- People on multiple medications.
Menopause and hot flushes
Hot flushes refer to a sudden increase of blood flow, often to the face, neck, and chest, that causes the sensation of extreme heat and profuse sweating. In women these can be related to menopause and symptoms should be checked by a gynaecologist.
The time of a woman’s life when her ovaries stop releasing an egg (ovum) on a monthly cycle, and her periods cease
Full medical glossary