RNCh,
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i"t can happen every time when you hold a chilled can of soda or step into an air-conditioned movie theater. Suddenly, your fingers turn icy, white and numb. And your feet are so sensitive that they feel frozen to the bone after doing the dishes while standing on cool kitchen tiles. But sometimes the temperature isn't the cause at all. For some people, emotional stress is enough to turn their fingers and toes to ice.
An estimated 2 to 6 percent of all Americans have hands and feet that are overly sensitive to chilly temperatures and stress. Doctors call the condition Raynaud's syndrome, after the French physician who discovered it. With Raynaud's, a dip in the temperature or a rise in stress levels causes the small blood vessels in the extremities to go into spasm, narrowing to the point that blood can barely circulate through them. Fingers and toes turn waxy white, then blue, and are numb and cool to the touch. Then, when the fingers and toes get warm, they flush deep red and tingle and throb as blood returns full force. This kind of episode can take anywhere from a few minutes to several hours.
Seventy-five percent of people with primary Raynaud's syndrome—the most common kind—are women under 40. It's unclear why. "My guess is there's a link to female hormones, which affect the blood vessels," says Fredrick Wigley, M.D., director of rheumatology at Johns Hopkins University School of Medicine in Baltimore. In any case, the color changes, numbness and tingling may be the only symptoms, and they may get worse or better. The problem usually improves dramatically by menopause.
Secondary Raynaud's—a less common but potentially more serious kind—usually targets women over 40 and men. Factors that act on the blood vessels may trigger the problem. These include smoking, high blood pressure medicines and diseases such as rheumatoid arthritis, lupus (an autoimmune disease) and atherosclerosis. Certain wrist-flexing, wear-and-tear activities such as typing or operating vibrating power drills may increase susceptibility to secondary Raynaud's. "