Why Do Some People Faint Because Of The Heat?

A dizzy feeling, a spinning head, nausea, excessive sweating… For some people this is an all too familiar situation. Commonly known as hot flushes, these are a common condition for some people.

What are hot flushes?

Hot flushes, also known as hot flashes or heat flushes, is a conditioned characterized by a feeling of excessive heat. It usually affects the area around the neck, chest and the face. The symptoms start with sweating and the feeling of losing energy from the limbs. The skin might also turn red due to extra blood pumping through it.

It occurs when the body detects a change in the internal temperature of the body and reacts to correct the change. The heart rate increases, causing an increase in the blood flow. Vasodilation, or the widening of blood vessels, occurs to release more heat through the skin. The sweat pores open so that sweat can be produced to cool the body. The increased blood flow also makes the skin appear red, as though the person is blushing.

These heat flushes typically last from a few minutes to around 10-15 minutes. When it begins to pass, the body might feel cold due to the loss of heat. However, it might take about 10-20 minutes after that for the person to completely recover. Heat flushes may occur with a frequency of a few times a week to a couple times each day.

sweating women

Heat flushes cause excessive sweating (Photo Credit : Flickr)

What causes hot flushes?

As the name suggests, these are caused by heat. However, there is a deeper reason. Hot flushes are a very common symptom in women who are entering or going through menopause. Menopause is the phase of a woman’s life wherein she is no longer fertile, and her menstrual cycle stops. This leads to an imbalance of the hormones oestrogen and progesterone. Oestrogen, for some unexplained reason, has a direct impact on the hypothalamus. This is a part of the body located near the nape of our neck and is the temperature control center of our body. When it is affected by oestrogen fluctuations, it tends to malfunction. Even a tiny drop or rise in temperature is misperceived as a major change, so the body has an extreme reaction.

However, hot flushes are not just seen in menopausal women. These are even known to occur in teenagers, both males and females, and even adult men. Oestrogen fluctuations are not the case in these instances. Hot flushes are also triggered by other factors, such as alcohol consumption, smoking, the consumption of drugs, including cannabis, etc. These are things that heat up the body from inside. Sometimes, some medicines and drugs interact with each other, or with other substances, like alcohol, which can also cause heat flushes. Sometimes, some people are generally more sensitive to heat. For such people, these flushes may occur in relatively hot or warm temperatures. Sometimes heat flushes can occur after intense workouts or strenuous activity.

sweating person

Skin usually turns red during a heat flush (Photo credit : Wikimedia Commons)

Are hot flushes dangerous?

In a lot of cases, these heat flushes are not considered dangerous. While they can be a source of discomfort, they cannot be classified as dangerous. While there have been cases where a person has passed out due to these flushes, the heat flush generally builds up, giving the person enough time to get to a safe place and cool off. However, if the frequency increases drastically, or if their intensity and severity increase to a level where they hinder one’s daily activities, it is best to have it checked out by a doctor.

While these are common in pregnant and menopausal women, if they occur in younger people, it is advisable to go to a doctor to determine their cause. It is important to keep in mind that these usually occur due to an increase in the internal temperature, rather than the outside. Therefore, it is safer to avoid certain habits and the consumption of things that can heat up the body. For instance, the consumption of spicy food or smoking can be eliminated, and you may notice the frequency of these flushes to also diminish.


  1. Healthline Networks
  2. Everyday Health
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About the Author:

Mahak Jalan has a BSc degree in Zoology from Mumbai University in India. She loves animals, books and biology. She has a general assumption that everyone shares her enthusiasm about the human body! An introvert by nature, she finds solace in music and writing.

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