Introduction: There is evidence that Yoga may be helpful as an aid for smoking cessation. Yoga has been shown to reduce stress and negative mood and may aid weight control, all of which have proven to be barriers to quitting smoking. This study is the first rigorous, randomized clinical trial of Yoga as a complementary therapy for smokers attempting to quit.

Methods: Adult smokers (N = 227; 55.5% women) were randomized to an 8-week program of cognitive-behavioral smoking cessation and either twice-weekly Iyengar Yoga or general Wellness classes (control). Assessments included cotinine-verified 7-day point prevalence abstinence at week 8, 3-month, and 6-month follow-ups.

Results: At baseline, participants' mean age was 46.2 (SD = 12.0) years and smoking rate was 17.3 (SD = 7.6) cigarettes/day. Longitudinally adjusted models of abstinence outcomes demonstrated significant group effects favoring Yoga. Yoga participants had 37% greater odds of achieving abstinence than Wellness participants at the end of treatment (EOT). Lower baseline smoking rates (≤10 cigarettes/day) were also associated with higher likelihood of quitting if given Yoga versus Wellness (OR = 2.43, 95% CI = 1.09% to 6.30%) classes at EOT. A significant dose effect was observed for Yoga (OR = 1.12, 95% CI = 1.09% to 1.26%), but not Wellness, such that each Yoga class attended increased quitting odds at EOT by 12%. Latent Class Modeling revealed a 4-class model of distinct quitting patterns among participants.

Conclusions: Yoga appears to increase the odds of successful smoking abstinence, particularly among light smokers. Additional work is needed to identify predictors of quitting patterns and inform adjustments to therapy needed to achieve cessation and prevent relapse.

Implications: This study adds to our knowledge of the types of physical activity that aid smoking cessation. Yoga increases the odds of successful smoking abstinence, and does so in a dose-response manner. This study also revealed four distinct patterns of smoking behavior among participants relevant to quitting smoking. Additional work is needed to determine whether variables that are predictive of these quitting patterns can be identified, which might suggest modifications to therapy for those who are unable to quit.