Dr. Z's oxygen concentrator?

Is anyone familiar with this machine? http://www.drz.org/asp/personal_portable_oxygen_O2_bar.asp


I bought it and notice nothing -- no increased energy, no health improvement whatsoever. I have candida and was hoping it would help oxygenate my body. Are oxygen concentrators effective to that end? Is there a machine that's better anyone would recommend?

Thankyou, I appreciate input very much!

Jan Tweet