What is the fine-grained topic of the following text: I doubt I have saved any money yet as it turned into a hobby (trying new devices, making my own juice(store bought juice is crazy expensive versus DIY)) but my asthmatic lung capacity has increased dramatically (longer walks, bike rides, etc) and no more bouts of bronchitis twice every year anymore. Only return the topic.
Benefits of DIY e-juice for vaping on health and finances