Smoking is a risk factor for erectile dysfunction. Several studies demonstrate an increased risk with greater exposure to cigarette smoke. Cessation of smoking may lead to a recovery of erectile function if smoking was for a limited time.
U.S. Department of Health and Human Services. The Health Consequences of Smoking – 50 years of Progress: A Report of the Surgeon General. Atlanta, GA. Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014, page 530.