Does Vaping Break Your Fast?, Sayyid Kashmiri explains that, according to Sayyid Sistani, both vaping and smoking invalidate the fast as a matter of obligatory precaution. Smoking has long been debated by Muslim scholars, with some calling it haram and others classifying it as makruh tahrimi, a level of prohibition just below haram. Dr. Shabir Ally explains the spectrum Ramadan: Can you vape while fasting? The Independent Can Muslims Smoke? Studio Arabiya