We’ve all had the feeling. You’re embarrassed and then there it is: a warm flush creeping up your neck and across your cheeks. The more you think about it, the hotter and redder you get. If someone asks “are you blushing?” it only makes you blush more.

So, why do we do it? When we’re already self-conscious, this involuntary response can feel like an added punishment. But evolutionary science suggests blushing may actually have social advantages. Let’s take a look.

Blushing is our body’s visible reaction when we feel emotions such as embarrassment, shyness or self-consciousness.

It’s caused by a short burst of increased blood flow to the skin of the ears, face, neck or chest.

When an emotion triggers blushing, the sympathetic nervous system – which controls automatic body functions – becomes active and releases adrenaline (epinephrine). This makes the tiny muscles in blood vessels relax.

In the body, adrenaline tightens blood vessels, but in the face it does the opposite – they dilate. This means more blood flows through to the skin and makes the face feel hot.

We turn red because of this sudden rush of blood close to the surface of the skin.

People with lighter skin tones show this redness more clearly. In darker skin tones, the change may be less visible or not visible at all – but the same physiological process still happens.

No matter whether others can see it, you’ll still feel warmth or tingling in your face.

People blush when they are feeling highly self-conscious, which is........

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