Filed under: Brain & Nervous System
Amyotrophic lateral sclerosis (a-mi-oh-TROH-fik LAT-ur-ul skluh-ROH-sis), or ALS, is a serious neurological disease that causes muscle weakness, disability and eventually death. ALS is often called Lou Gehrig's disease, after the famous baseball player who was diagnosed with it in 1939. In the U.S., ALS and motor neuron disease (MND) are sometimes used interchangeably.
Worldwide, ALS occurs in 1 to 3 people per 100,000. In the vast majority of cases — 90 to 95 percent — doctors don't yet know why ALS occurs. About 5 to 10 percent of ALS cases are inherited.
ALS often begins with muscle twitching and weakness in an arm or leg, or with slurring of speech. Eventually, ALS affects your ability to control the muscles needed to move, speak, eat and breathe.
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Read this article on Mayoclinic.com.

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