Raynaud's disease review by Mayo Clinic Health Letter

There's a medical reason behind cold fingers and toes, when a chill seems to instantly turn extremities white.

The May issue of Mayo Clinic Health Letter explains the likely cause: Raynaud's (ray-NODES) disease, a disorder of the blood vessels.

Exposure to cold normally results in slowing of blood flow to fingers and toes. Small arteries in extremities narrow, reducing blood flow and preserving the core body temperature. For people with Raynaud's disease, the response is exaggerated for unknown reasons. The small arteries constrict dramatically, most often in the fingers and toes, but the nose, ears and cheeks also can be affected. The constriction, called vasospasm, can last for a little as a minute or as long as several hours. Stressful emotions can trigger vasospasm, too.

There's no known cause of Raynaud's, which most often first occurs between teen years and about age 40. In some cases, it is linked to diseases that can damage blood vessels or nerves, such as scleroderma, lupus or rheumatoid arthritis.

In many cases, Raynaud's doesn't cause any permanent damage. Some people with severe Raynaud's do experience tissue destruction and should seek medical treatment to manage the condition. Medications that relax blood vessels and promote circulation can help. They include calcium channel blockers, alpha blockers and bosentan (Tracleer). Most people with Raynaud's find the condition can be uncomfortable but managed with lifestyle changes such as dressing to avoid chills. And Raynaud's disease is yet another reason to avoid cigarettes. Nicotine constricts blood vessels.