found this statement in another forum:
Androsterone is a steroid metabolite of testosterone with weak androgenic properties. Specifically, it is the 3-hydroxyl, 17-keto isomer, of testosterone. Androsterone has no known anti-estrogenic properties. Supplementation with excess amounts of androsterone will undoubtedly trigger the negative feedback within the HPTA leading to lower natural testosterone levels. For someone coming off a steroid cycle, supplementing with Formadrol will probably prolong their recovery until supplementation ceases.
and this answer from lg:
Androsterone has LOTS of studies showing anti-aromatase effects. Daidzin has been shown in studies to stimulate growth. Your paper on Female mice with their overaries removed isn't really relevant and they used synthetic equol at that in the study. So, clearly it doesn't appear to have much merit in the conversion rate. ATD is in there which is also good as an AI.
"Androsterone is a steroid metabolite of testosterone with weak androgenic properties. Specifically, it is the 3-hydroxyl, 17-keto isomer, of testosterone. Androsterone has no known anti-estrogenic properties. Supplementation with excess amounts of androsterone will undoubtedly trigger the negative feedback within the HPTA leading to lower natural testosterone levels. For someone coming off a steroid cycle, supplementing with Formadrol will probably prolong their recovery until supplementation ceases."
I will go point by point to show that you don't know everything.
You say "Androsterone has no known anti-estrogenic properties"
1: J Clin Endocrinol Metab. 1984 Mar;58(3):467-72.Links
The intracellular control of aromatase activity by 5 alpha-reduced androgens in human breast carcinoma cells in culture.Perel E, Stolee KH, Kharlip L, Blackstein ME, Killinger DW.
To determine if the 5 alpha-reduced androgen metabolites formed within the breast carcinoma cells could influence aromatase activity, the MD line was further studied. After 24-h preincubation with AND, DHT, or 5 alpha-A-dione at concentrations of 10(-6), 10(-7), and 10(-8) M, [3H]androstenedione was added to the culture medium, and aliquots were removed at 0, 4, 8, and 24 h. An 8-h incubation period was found to be optimum for inhibition studies. In comparison to control levels of estrone (2.5%) and estradiol (0.35%) formation, inhibition of aromatization was evident with all three compounds at 10(-8) M, with 5 alpha-A-dione producing the greatest inhibition (50%). At 10(-7) M, inhibition ranged from 45% (ANDROSTERONE) to 70% (5 alpha-A-dione), and at 10(-6) M, inhibition was greater than 90% for each compound. 5 alpha-A-dione produced slightly greater inhibition than ANDROSTERONE or DHT at each concentration tested. Since each of these compounds was capable of inhibiting aromatization, the cumulative effect of these 5 alpha-reduced metabolites could be an important factor in the intracellular regulation of aromatase activity.
Aromatase activity in the breast and other peripheral tissues and its therapeutic regulation.Killinger DW, Perel E, Daniilescu D, Kharlip L, Blackstein ME.
Department of Medicine, University of Toronto, Ontario, Canada.
Using cultured breast carcinoma cells, it was shown that estrogen formation was stimulated by cortisol (10(-6) M) and inhibited by endogenous 5 alpha-reduced androgens: 5 alpha-androstene-dione greater than androsterone greater than dihydrotestosterone greater than epiandrosterone greater than 3 alpha- and 3 beta- androstanediol.
but then another statement from the op as an answer:
Those studies had to do with substrate availability. In the human body, endogenous testosterone production will not be suppressed systemically for this to occur. And unless you are developing a topical androsterone cream, neither of those studies were relevant to what we were discussing. Specifically, I said androsterone has no anti-estrogenic properties.
The studies you mentioned display the obvious: 5a-reduced androgens cannot convert to estrogen via the aromatase enzyme. Without a subtrate for estrogen production (IN A CLOSED SYSTEM [en vitro]), estrogen levels will go down. Your logic is that if one supplements with a 5a-reduced androgen, then estrogenic symptoms will not occur. I think you now see the flaw in your argument. In retrospect, I do apologize for the title of this thread.