People who smoke are more likely to have seizures than those who don't, while caffeine and alcohol do not increase the chances, according to a new study.

Researchers from Brigham and Women's Hospital and Harvard Medical School used data from a study of more than 116,000 female nurses who answered questions about their health.

"Our analysis showed risk of seizure was significantly higher for current smokers, but not related to the amount of cigarettes smoked daily," said Dr. Barbara A. Dworetzky. "It does appear, however, that the number of years of smoking does increase seizure risk."

The team also found that long-term caffeine consumption did not raise the risk of seizures or epilepsy compared to people who had less caffeine.

The full study appears in the February 2010 issue of Epilepsia.