A new study published in Nicotine & Tobacco Research found that those using e cigarettes alone were more than twice as likely to develop COPD than people who didn't use any tobacco products, Exclusive E cigarette Use Significantly Associated with COPD RT Does Vaping Cause Lung Cancer? Full article: Health impact of e cigarettes and heated tobacco products in chronic obstructive pulmonary disease: current and emerging evidence Exclusive e cigarette use raises COPD risk but not type 2 diabetes or heart failure risk E cigarettes use in the United States: reasons for use, perceptions, and effects on health BMC Public Health Springer Nature Link