Skip to navigation Skip to content

Unhealthy Habits

Smoking can impact the risk of getting MS as well as the progression of MS. Alcohol affects the central nervous system.


In this article
The Office of the U.S. Surgeon General has established that smoking causes serious health problems; subsequent studies by many other groups have confirmed this. Smokers are generally recognized to have higher rates of lung cancer, heart disease, emphysema and other respiratory problems, and lower birth weight infants than nonsmokers. Smoking is known to produce shortness of breath, susceptibility to lung infections, and heartbeat irregularities, which might transform a mild or moderate neurological limitation in a person with MS into a severe disability. Furthermore, smoking presents a significant fire hazard when the smoker suffers from weakness or incoordination.

Smoking may increase risk of developing MS

  • In a Norwegian city study published in Neurology in 2003, the risk of MS was significantly higher among smokers than among those who had never smoked.
  • Researchers showed that two individual factors that were previously identified as increasing the likelihood of developing MS – exposure to Epstein-Barr virus and tobacco smoking – may interact and multiply to substantially increase the risk of developing MS in those with both risk factors.

Smoking can worsen MS

In addition to general health and safety concerns, smoking increases a person's risk of developing MS and of disability progression.
  • A new summary paper outlines the considerable evidence that smoking is a modifiable risk factor in the development and progression of MS. 
  • A 2005 paper in the journal, Brain, supported the link between smoking and the risk of developing MS, and suggested that smoking may be a risk factor for transforming a relapsing-remitting clinical course into a secondary-progressive course.
  • Researchers recently reported links between smoking and brain tissue damage observed on MRI (magnetic resonance imaging) scans of 368 people with MS.
  • In a study comparing 1465 smokers, ex-smokers and never-smokers, all of whom had multiple sclerosis, MS disability progressed more quickly in smokers, and this difference was also noted in MRI measures of disease activity. For several measures, ex-smokers did not differ substantially from never-smokers, suggesting that quitting may delay MS progression.
  • In a study of nearly 700 people whose medical records were reviewed by researchers in Sweden, current smokers were significantly more likely to develop antibodies associated with immunity to interferon beta treatment for MS than non-smokers.
  • The Ausimmune Study, partly funded by the Society, was undertaken to investigate whether increased exposure to sunlight and vitamin D may be protective against MS in people who had not yet been diagnosed with MS, but who had experienced a first neurologic episode that often leads to MS (CIS -clinically isolated syndrome); in a follow-up study, they found that the risk of developing a CIS increased by 79% in people who had ever smoked.


The National Institutes of Health provides resources to help quit smoking. Visit or call 800-QUITNOW (800-784-8669).

Additional resources