When it's chilly, the nation’s million Raynaud’s sufferers certainly feel the cold.

The condition, which usually strikes hands in cold temperatures or during periods of stress and anxiety, prevents blood from reaching the body’s extremities.

[Read more: Hay fever or cold – how to tell the difference between the symptoms]

Because of this, the affected area – usually hands - turn white, and then blue, then red, as the blood flow finally returns and can cause feelings of numbness, pins and needles or pain.

Mostly associated with the colder months, the condition is actually as common as hayfever (Raynaud's alleviating capsule brand PADMA CIRCOSAN estimates it affects around 10 million people in the UK) and can flare up in the summer, triggered by things like holding a cold drink, ice lolly or going into air conditioned buildings.

TV and radio host Jenni Falconer, who suffers from the condition, commented: "Bizarrely, it doesn’t have to be a bitterly cold day to bring it on. One summer I holidayed in the Maldives and was relaxing on a beach in a bikini. Suddenly, a cooling breeze sprung up and whereas most people probably welcomed it, I didn’t because it brought on Raynaud’s."

We look at the causes, symptoms and treatment for the condition.

[Read more: Cold weather payment: What is it, how to claim and how much you'll get]

What is Raynaud’s?

Primary Raynaud’s sufferers are affected in their hands, with digits turning pale, whereas people with secondary Raynaud’s will find their feet are affected.

It’s also worth noting that while primary is just the condition on its own, secondary, which is much less common, is an extra symptom from another condition.

Often, this other condition is an autoimmune disease, like rheumatoid arthritis or lupus.

What else does Raynaud’s affect?

Raynaud’s can also affect your feet, nose, ears or nipples.

Do I have Raynaud’s?

To test, look out for these stages…

  1. The affected body part turns white, because blood supply is restricted.
  2. A lack of oxygen turns the area blue, making the area feel cold and numb.
  3. As blood returns at a higher rate than normal, the skin turns red, and will probably be accompanied by tingling, or a throbbing sensation, and maybe some swelling.

[Read more: Poor circulation and what causes it]

What causes Raynaud's?

Experts are still trying to find a root cause for the condition but some have suggested it may be linked to alterations in the chemicals which narrow blood vessels, or an increased sensitivity in the nerve endings of blood vessel walls. Check in with your GP for help on how to manage the condition.

What can I do to help myself if I have Raynaud's?

  • Wear insulated gloves before going into the fridge or freezer and avoid touching cold surfaces and objects.
  • Warm your clothes and shoes with a blast of the hairdryer before going outside.
  • Use warm hand dryers when you’re in public places.
  • Stick with shoulder bags to carry your food shopping in rather than plastic carriers or bags with handles which can restrict blood to the fingers. 
  • Stop smoking. Doing so will improve your circulation which should help with the condition.
  • Regular exercise should also help improve circulation.
  • Identify your triggers. Knowing whether it’s stress, or air conditioning or cold weather that triggers your condition can help you prepare and avoid making it worse.

Visit raynauds.org.uk for help and support