MS is an auto-immune disease, much like Lupus, Diabetes, rheumatoid Arthritis and a host of others. MS is the result of the immune system mistakenly attacking and destroying healthy body tissue, which is what happens in any auto-immune disorder. It is unknown what causes auto-immune diseases. Possible theories include stress and/or food additives, but there is no evidence to categorically state the cause. There is no prevention and no cure. Auto-immune diseases require different levels of intervention and medical treatment, but for the most part are manageable. None are genetically linked and none are the result of "an irresponsible lifestyle."