Cold hands and numb fingers are among the common symptoms.

If you have become used to seeing your fingers and toes turn white when the temperature drops, you may be suffering from a medical condition called Raynaud's syndrome.

@corycalendinemd Raynaud's phenomenon (Raynaud's syndrome) is a condition that causes spasms in small arteries leading to reduced blood flow to the extremities. #Raynaud episodes or "attacks" usually affect the fingers or toes, but can also affect the ears, nose, nipples, or lips . Attacks are usually triggered by exposure to cold, stress, or emotional upset (Fingers or toes turning white or pale, Fingers or toes turning blue, Numbness, and Pain) Symptoms can last from seconds to minutes, and often resolve on their own when the hands are warmed and blood flow returns (known as triphasic color change - fingers or toes initially turning white or pale, then blue, and finally red. Less commonly, Raynaud's phenomenon can be a sign of an underlying autoimmune disorder, such as lupus, scleroderma, or rheumatoid arthritis. It's important to see a doctor for correct diagnosis and treatment options. #raynauds #raynaudsdisease ♬ The Champion - Lux-Inspira

Raynaud's syndrome occurs when blood vessels in the fingers or toes suddenly narrow or spasm, leading to a blue discoloration, followed by a sharply demarcated pale white discoloration, and finally, a red discoloration.

It can often be symmetric, affecting fingers on both hands.

The phenomenon was first described by the 19th century French medical student Maurice Raynaud.

According to the NHS, it's extremely common and does not usually cause severe problems.

While it's not exactly life-threatening, if you have happen to notice your fingers or toes turning red, white and blue this winter, you should speak to your dermatologist.

For some, Raynaud's is the first sign of underlying illness, and there may be lifestyle changes and medical treatments that can help.

Dr. Emily Kiemig, a dermatologist and assistant professor at Northwestern's Feinberg School of Medicine in Chicago who frequently cares for patients with Raynaud's, said: "It's really an exaggerated cold response: When our body is cold it's normal for our blood vessels at the periphery, such as in our fingers, to narrow to conserve core body heat.

"It's normal for fingers to turn a little blue when we're in a cold environment," she added, but when someone has Raynaud's, their blood vessels narrow, even at modestly cool temperatures, and remain clamped for long periods of time. Once the blood vessels return to a normal caliber, "blood flow rushes back in and the fingers will turn red."

Symptoms of Raynaud's may include numbness, tingling, discomfort and even throbbing pain. People who develop ulcers at the tips of the fingers should seek timely medical evaluation as breaks in the skin can lead to infection.

It is sometimes caused by another health condition or taking certain medicines; something your doctor can check out for you.

Raynaud’s is overwhelmingly more common with women and generally first discovered in adolescence. Up to 20 percent of the world's adult population suffer from Reynaud's.