I have been using the gsh now for about 6 months. I didn't think it was doing anything when I first started so stopped taking it and felt like crap. I was tired and could not fight off anything. went back on it and started having more energy and am able to fight colds and stuff pretty well. I have not noticed a change in fev with it b/c i am pretty low, 18%. It does make me feel alot better though.If u take it when u r younger it can help a great deal from what I have read. My password does not work right now but this is JOBLAZER86 and I am 21wcf.