If you or your loved one has received a diagnosis of multiple sclerosis (MS), you’re not alone. According to a landmark study published in the journal Neurology, an estimated 1 million people in the United States have MS—a number that’s two times higher than previous estimates.

“Many people find it helpful to start by gathering the facts—learning as much as they can about MS and getting answers to the most commonly asked questions,” says Hope Nearhood, the director of MS Information and Resources at the National Multiple Sclerosis Society (NMSS).