this is taken off of another forum, I copied and emailed to a friend without siting it so I no longer know where it is from. Sorry for the way it formatted.
"First you need to understand what tells your body to make test. It's estrogen.
It gets a little confusing if you're not familiar with the way Aromatese Inhibitors work.
There is only one estrogen receptor so they all want to do the same thing. Limit the estrogen that binds to that receptor. Nolvadex, not an AI, does it by binding to it itself and blocking off the estrogen from being able to affect you.
Then comes the AI's which work one of two ways. They either inhibit the aromatese enzymes from converting the test in your blood to estrogen OR they kill the aromatese off (called suicidal) so that they aren't there to convert the test to estrogen.
So your reference to irreversible pertains to the later, a suicidal aromatese inhibitor.
Arimidex is one that only inhibits the aromatese from converting test to estrogen. It was one of the first introduced. It works much better in women than in men. In men it's only preventing a little over half of the conversion. And that’s at 1mg/day.
Aromasin is suicidal and kills off the aromatese enzyme so it's much more powerful and does a better job in men and women.
The AIFM from the AF Store is suicidal and is much stronger than Arimidex for that reason. If you have REAL aromasin pills then you are taking the best AI there is. And with proviron you should do very well.
AI's are used to increase natural test levels. They do this by lowering estrogen. HUH? Yes by lowering estrogen you raise test in your body. That's because your body doesn't measure the amount of test you have to determine if it should make more. The HPTA (system controlling your test) "knows" that test is converted to estrogen by the aromatese. So when the HPTA reads low estrogen it signals the testes to start producing more test. So when you use AIFM or similar AI you lower your estrogen levels, this triggers the HPTA to read "we need more test down there" and your test levels then go up as the testes start pumping it out. The AI will continue to limit the conversion and the HPTA will continue to read low estrogen and keep your natural test levels at the high side or normal."
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