Hot Flushes or Hot Flashes – Why Do They Happen?

hot flush in sun

Body temperature fluctuations? Today it’s all about them, one of the peskiest signs of the meno years. Our resident biochemist Peter Lehrke talks us through the science.

They are something worth knowing a bit about because they last for seven years on average.

Arrgh! What’s Happening To Our Body?

Let’s talk about what is actually happening throughout your body when you experience them. The story starts in a distant time, in your own Middle Earth; the small planet earth shaped organs deep in your middle – the ovaries.

Ovaries: Once upon a time, before you were perimenopausal, your ovaries produced large quantities of estrogen and progesterone. As you age the ovaries start to reduce a number of these hormones that they produce. This starts to affect the entire ecosystem of your internal universe.

Brain: declining estrogen confuses the brain. In particular, the hypothalamus, the area responsible for producing hormones that control hunger, mood, and body temperature. A sudden drop in estrogen spurs it to tell the body you are too hot, even when you are not even feeling warm.

Heart: in response to the overheating alert from the hypothalamus, the brain triggers the nervous system alarms, sending stress and mood hormones shooting through your system (adrenalin, noradrenalin, prostaglandin, serotonin). This turns on the cooling mechanisms in the skin, heart and sweat glands.

Mood: You may feel tension or dread before a body temperature fluctuation, or you may even experience an aura, visual signs like dark spots or flashing lights. This is caused by changes in the cortex area of the brain where we experience sensations.

Skin: Your skin temperature can rise 50 to 70C, an extreme change. And it will feel like a massive surge of heat. However, your internal organs and your core body will remain constant and normal temperature.

Blood Vessels: Your heart beats faster to increase blood flow to your skin in order to get the blood vessels to dilate, or open up. This helps get rid of heat from the skin, and what causes the signature, attention-getting hot-flash look; a flushed face and upper body.

Sweat Glands: To cool the body down the sweat glands release sweat, which then evaporates, lowering the temperature and cooling you off. Then you may actually feel cold.

All of this happens in a flash, leaving you rather flushed!

woman with fan

Why does this happen?

Although we know what happens, medical science does not yet know the full reasons why they occur in most women, yet not at all. However, we do know that certain non-menopausal factors can make these signs worse.

  1. Certain medications – opioids, antidepressants, and some osteoporosis drugs are a few of the common medication triggers.
  2. Medical conditions – in particular, thyroid issues, infections or viruses will increase body temperature, often in waves.
  3. Excess weight – body fat is metabolically active, which helps explain the links between obesity and some cancers. A study at the University of California showed that by reducing weight and exercising you can be twice as likely to reduce body temperature surges.
  4. Food allergies or sensitivities – alcohol, caffeine and additives like sulphites are common triggers. Certain foods, especially very spicy foods can also set off the cascade of hormones that result in body heat.
  5. Anxiety – in fact, any stress that results in adrenalin and cortisol release can turn up the body’s thermostat and make you vulnerable.
  6. A hot bedroom – body temperature naturally fluctuates throughout sleep and it is common for both women and men to wake up in the middle of the night feeling overheated or sweaty.

What Can You Do?

  1. Check the side effects of any medications you are taking and discuss these and any medical conditions with your healthcare professional. There may be alternatives with less severe side effects. 
  2. Check your weight.
  3. Keep a diary, and especially record foods that you have eaten that could be making signs worse. Consider cutting down our cutting out alcohol and caffeine, and look out for food additives on labels of the foods you eat.
  4. De-stress – monitor your stress and anxiety levels in your diary, and see if there is any pattern of association with your hot flash signs. If you do feel anxious remind yourself to breathe through any tense or uncomfortable moments. Exercise, yoga and meditation all help to reduce anxiety.
  5. At night ensure your sleepwear and bedding are appropriately light and crack open a window for more fresh air circulation.

Finally, remember body temperature  surges are a transient phenomena, and at MenoMe® we are here to help you through it.

Peter Lehrke
Nutritional Biochemist.


Scroll to Top