Also known as disseminated sclerosis or encephalomyelitis disseminate, multiple sclerosis (MS) is a chronic, often disabling autoimmune disease that affects an estimated 400,000 Americans, according to the National Multiple Sclerosis Society (NMSS). The condition causes the immune system to attack the central nervous system, and symptoms may include limb numbness, paralysis, or loss of vision.

That said, the progression of multiple sclerosis differs from person to person, so it's hard to gauge how the disease will affect each individual. In fact, there are four recognized disease courses for MS, each of which may include mild, moderate, or severe symptoms. Perhaps for this reason, there continues to be many misconceptions about multiple sclerosis's causes, treatments, and prognosis. Here, we dispel the top eight myths.

Myth #1: Multiple sclerosis is fatal.

Fact: Contrary to popular belief, MS is rarely terminal. In fact, according to the NMSS, most people with MS have a normal or near-normal life expectancy. That said, severe cases of MS can shorten a patient's life span.

Myth #2: There is no treatment for multiple sclerosis.

Fact: Although there's no cure for the disease, there are treatments available to help patients cope with the condition. Some patients fare better without medication, but for certain relapsing-remitting cases, beta interferon therapies have been shown to reduce the number of exacerbations and may slow the progression of physical disability, the National Institutes of Health report. In addition, a synthetic form of myelin basic protein may be prescribed for the treatment of relapsing-remitting MS, while immunosuppressant treatment may be useful in treating advanced or chronic forms

Myth #3: Multiple sclerosis means being confined to a wheelchair.

Fact: Multiple sclerosis patients may experience mobility issues as the disease progresses, but only an estimated 25 percent use a wheelchair. Some patients may not use any mobility device, while others rely on a cane or scooter.

Myth #4: People with multiple sclerosis can't work or have children.

Fact: While most experts advise that people with MS avoid occupational stress, many continue to work full time or in lower-stress settings. Generally, there's no reason why women with MS can't give birth. In addition, the risk of prospective parents passing on MS to their children is only between 1 and 5 percent.

Myth #5: Multiple sclerosis isn't a physically painful condition.

Fact: Most people may associate MS with numbness, but that doesn't mean many patients don't also experience physical pain. According to one study, up to 55 percent of MS patients experienced clinically significant pain, whether acute or chronic, at some point during the course of the disease.

Myth #6: Multiple sclerosis only affects Caucasians.

Fact: The prevalence of MS in the United States is higher in whites than in other racial groups, but that doesn't mean it affects only Caucasians. What's more, according to a study supported by the National MS Society, African Americans with the condition are more likely to experience a more aggressive course of disease.

Myth #7: Multiple sclerosis is caused by a poor diet or negative thinking.

Fact: Although scientists have yet to identify a single cause for MS, they do know that it's not the result of a poor diet or negative attitude. Current data suggests that MS is caused by a combination of environmental and genetic factors; in addition, some studies indicate that hormones and viruses may play a role.

Myth #8: Multiple sclerosis can be cured through dietary changes or optimism.

Fact: A balanced diet and optimistic outlook are recommended for everyone. But there is no evidence that these types of lifestyle changes can cure multiple sclerosis.