Blushing is caused by the sympathetic nervous system the network of nerves responsible for triggering your 'fight or flight' reflex.
The sympathetic nervous system is a series of involuntary physical changes to your body when faced with a stressful or dangerous situation.
A sudden and strong emotion such as embarrassment or stress causes your sympathetic nervous system to widen the blood vessels in your face. This increases the blood flow to your skin, producing the redness associated with blushing.
In addition to emotional triggers, other causes of blushing can include:
There are a number of medical conditions that can cause a person to blush frequently, including both psychological and physical problems.
A common cause of excessive and frequent blushing is having an irrational fear ( Phobias ) of blushing, known as erythrophobia. People with erythrophobia often worry that they'll blush when interacting with others, and that other people will mock them because of this.
Unfortunately, this can trigger a vicious cycle. They become so worried about being the centre of attention in social gatherings that when it happens, they suddenly become very embarrassed and start blushing, which reinforces their phobia.
Erythrophobia is often associated with other phobias and mood disorders, such as social phobia and general anxiety disorder (GAD) .
Blushing can also sometimes be associated with other medical conditions, including:
Although it isn't a direct cause of blushing, excessive sweating (hyperhidrosis) is often associated with the condition.
Certain types of medication can also cause blushing. These include:
Speak to your GP if you're taking a medication that causes blushing and it's making you feel worried, stressed or self-conscious. They may be able to recommend an alternative medication.
Find out what can cause abnormal (severe and frequent) blushing, when to seek medical advice and the available treatment options.
Read about what causes blushing, including emotional triggers, such as embarrassment, physical triggers, such as alcohol, and certain medical conditions and medications.
Read about the treatments for blushing, which will depend on what's causing it. A talking treatment, such as CBT, may be recommended if it's caused by an irrational fear.