Do AI's Lose effectiveness??

[reddragon4954]

Dont breath to much into the question just more for curisoity. Pros as most understand it, stay on gear year round. They use AI's (adex,letro,aroma) and stuff for 10 years at a time when you consider most started very young...

My question is do AI's over time lose potencty on your body or simply just stop working for you at some point or will AIs lose maybe lose a little efficeiency over the course of the years but negligable in terms of it actully effecting you in the sence that the AI no longer works...???

[reddragon4954]

So, is the AI loseing effectiveness just a myth or what...? Especailly with something like Aromasin...I mean aromasin doesnt block estrogen so your body never stops producing estro while on aromasin like it does wit adex or letro, it merely makes the aromatose enzyme impossible to function, so I would think b/c it deactivates the enzyme and does not merely block production that Aromasin at least could be used long term with no problem it losing effectivenss..