A new Harvard University study shows smoking may increase the risk of getting multiple sclerosis.

Researchers found a consistent link between MS, smoking and the body's immune response to the Epstein-Barr Virus, a condition that is often found in people with MS.

Specifically, the study found smokers were twice as likely to have MS as those who had never smoked.

Multiple Sclerosis, an incurable condition, is the most common disabling neurological disease among young adults in the U.S. and affects approximately 2 million people worldwide.