Compared with never smokers, the HR for incident diabetes was 1.00 (95% CI, 0.96-1.04) for former smokers, 1.20 (95% CI, 1.09-1.31) for continuing smokers, and 1.43 (95% CI, 1.26-1.63) for new quitters after confounders were adjusted for. During the first 3 years of follow-up, a weight gain greater than 5 kg occurred in 10.2% of never smokers, 11.6% of former smokers, 12.3% of continuing smokers, and 30.5% of new quitters (median weight gain, 2.9 kg vs 0.3-0.5 kg in all other groups of smoking status). After weight gain was adjusted for (Table), the risk of diabetes remained elevated among continuing smokers (HR, 1.20; 95% CI, 1.10 1.32) and attenuated slightly but remained significantly elevated among new quitters (HR, 1.36; 95% CI, 1.19-1.54). Among former smokers, the diabetes risk decreased significantly as the time since quitting increased, and the risk was similar to that of never smokers after a cessation period of 10 years. We examined whether the increased risk of diabetes in new quitters was explained by weight gain in the analysis stratified by weight gain (Table). Among former smokers, the risk of diabetes was not greater compared with never smokers with similar weight gain. Among continuing smokers, the risk of diabetes was significantly increased compared with never smokers, both in women who gained 5 kg or more and in those who did not (P for interaction, 0.4). Among new quitters, the risk of diabetes among women who gained less than 5 kg was similar to the risk in continuing smokers, although it was not significantly elevated in this relatively small subgroup. However, among new quitters who gained 5 kg or more, there was a 67% excess risk of diabetes compared with nonsmokers (P for interaction, .02).