People who start smoking before the age of 17 have an increased risk of developing multiple sclerosis (MS), a new study has revealed.
The research, led by Joseph Finkelstein of Johns Hopkins University School of Medicine in Baltimore, will present his findings at the American Academy of Neurology 61st Annual Meeting in Seattle at the end of April.
In the study, 87 people with MS were divided into three groups - non-smokers, early smokers and late smokers - as part of a wider study of 30,000 sufferers.
It was discovered that early smokers were 2.7 times more likely to develop MS, with late smokers not having any notably elevated risk.
Dr Finkelstein concluded: "Studies show that environmental factors play a prominent role in multiple sclerosis. Early smoking is an environmental factor that can be avoided."
This week, it was revealed by scientists at the Karolinska Institute in Sweden that being underweight or overweight as a teenager curbs life expectancy in a similar way to ten cigarettes a day.
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