Body Temperature

*This article is for information purposes only and is not medical advice. Always follow your doctor’s medical advice and seek medical help when necessary.

How is your body temperature regulated?

Our body cleverly regulates our body temperature and responds to different circumstances by sending out signals from the part of the brain called the hypothalamus. If your body temperature is too hot, the sweat glands are activated to bring water to the surface and as the water evaporates it has a cooling affect. When you are cold, the hypothalamus sends signals to your muscles to shiver and create warmth. The hypothalamus is always looking to regulate our body temperature to stay around 37°C.

Why do you get a high temperature when you are ill?

When you are fighting off an infection, your body makes more white blood cells to fight the infection. The increase in white blood cells sends signals to your hypothalamus which in turn recognises a war is on and increases your body’s temperature. This is a clever response because white blood cells can reproduce in warmer temperatures, but bacteria cannot reproduce as quickly – thereby tipping the odds in your favour.

Why do you shiver when you have a high temperature?

At the early stages of fighting an infection, your body’s aim is to keep all the organs that are fighting off the infection working hard, so your blood vessels constrict and force blood in the outer layers of the skin to move further into the body. This makes you feel cold as the heat from your skin is removed. The hypothalamus responds by sending signals to your muscles to start shivering to warm up again.

What can you do to help with a fever?

  • Get lots of rest
  • Drink plenty of water and fluid
  • Wear comfortable clothing that is neither too warm or too cool
  • Take paracetamol or ibuprofen if needed

When you should call a doctor:

  • If your temperature is over 38°C
  • An unusual rash appears
  • Difficulty breathing
  • Acting confused or disorientated
  • Blue, pale or blotchy skin, lips or tongue
  • Not passing urine
  • Severe shivering and muscle pain

Could you have something more than just a fever? Could it be SEPSIS?

Sometimes a temperature can indicate a lot more than just a cold. For example, Sepsis, which is a severe reaction to an infection, can be life-threatening if not addressed quickly. This can happen if you have recently had an injury or surgery. Sepsis can be linked to a high temperature as the body produces increasingly more white blood cells to fight the infection. Sepsis occurs when the infection spreads outside of the initial infected area. Eventually the infection spreads everywhere and causes organs to stop functioning. Initially, Sepsis can be mistaken for flu or a chest infection, but it can accelerate very quickly and become fatal – this is why it is important to monitor your symptoms and get immediate medical attention if they get worse.

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