How can oxygen therapy affect the body system?

Too much not good: Depends on why the oxygen therapy is given for. Is it for lungs , heart, or for helping wound healing ? If for lungs and if you have copd, too much oxygen may make you breath less and cause complications.

Helps it: If you need oxygen (i.e., your levels are low), then oxygen therapy is very good for the body. But, if your oxygen levels are already normal, then oxygen will likely not do anything. It may, in fact, be harmful. And...It is very expensive.

O2: Affects the body by increasing the delivery of o2 to the tissues that need it. This is only effective when there is o2 deprivation state as in hypoxemia of many causes or sepsis or in some poisoning to reverse the occupation of the poison on the hemoglobin so o2 can be carried and delivered. It can kill anaerobic bacteria. In other cases, it is all without proof of need. O2 is kreb's cycle.