Are there any studies showing that level is not abnormal for patients using TRT?
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I think it's useful to consider both absolute and relative estradiol. Your estradiol is 0.55% of testosterone. The normal range is roughly 0.3-0.6%. So no real problem here. This means there's probably nothing unusual about your rate of aromatization—that is, the rate at which testosterone is converted to estradiol. This is good, because it argues against an imbalance between estrogens and androgens.
Absolute estradiol is possibly more problematic. Because you're probably taking more testosterone than you ever could have produced naturally you are also creating more estradiol than you could make naturally. Average total estradiol for healthy young men may be around 30 pg/mL. Of course they're also sporting total testosterone of around 600 ng/dL, well under your level. In any case, your estradiol of 46 pg/mL is several standard deviations above the average. The long-term consequences of this are uncertain. For me personally, the only symptom clearly tied to higher absolute estradiol is heightened emotional responsiveness.
So what's wrong with taking an AI? First, as the others have pointed out, your initial dosing was not set responsibly. Anastrozole should probably be dosed in micrograms, not milligrams. When I was using it I maxed out at 50 mcg a day (0.35 mg/week), with 30-35 being more typical. These doses were sufficient to push estradiol down from 50s to 30s pg/mL. Regardless, a low-and-slow approach is advised to avoid over-suppression of estradiol.
Now what happens if you bring your estradiol down to ~30 pg/mL without other changes? Estradiol as a fraction of testosterone is reduced to 0.36%. That's still in the normal range, but is it normal for you? If you've lived your whole life with a somewhat higher ratio then is this shift in the balance going to be entirely benign? This is unknown.
More speculatively, does AI use lead to localized estrogen deprivation? Anastrozole is said to be more brain-friendly than other AIs. But does this suggest that if you were looking to reduce the emotional side effects of higher estradiol then you might only accomplish this by simultaneously reducing estrogen creation by too much elsewhere?
My predictable punchline is that the best approach is to reduce TRT dosing to achieve physiologically realistic levels, which will then be reflected in downstream hormones such as estradiol.