When you take testosterone your body makes the amount of estrogen you would naturally have at the levels the TRT produces. It maintains the estrogen/testosterone ratio. The normal estrogen levels used in labs are not the “normal levels” of men on testosterone. They are baseline levels. The harm of high estrogen levels (it’s not the estrogen causing harm it’s what is causing the high estrogen) are baseline observation studies in men who also have low T. No study has ever shown any adverse effects from raising estrogen when giving testosterone. In fact,EVERY study done showing the benefits of testosterone (and with raising testosterone they raised estrogen) they did not control or block estrogen.