A common factor in many health challenges is insufficient oxygen available to the bloodstream. When we ingest water with extra oxygen in it, it bypasses the lungs and is available for absorption into the blood stream. This increases the blood oxygen and can also take some of the load off of the lungs themselves making lung problems easier to address. Fresh rain water has oxygen in it. So do fresh vegetables and fruits.
Tap water has very little oxygen in it.
Neither does most bottled water. The pure water taste is quite refreshing and Oxywater caused my blood oxygen as gauged by a Pulse Oxymeter, to increase within 10 minutes after consumption. No fire hazard either. I am using it daily and triple my consumption when I fly in a plane, spend much time in an office building with windows that do not open or having had a particularly stressful day. Health professionals take special note.