Men have on average 300 times more testosterone than estrogen floating around in serum, even diagnosable hypogonadal men will still likely have over 100 times more testosterone than estradiol, and cycling females at the end of their follicular phase where estrogen is likely at its highest would still have around a 1:1 ratio of estradiol to testosterone.

AKA no one is really estrogen dominant…ever.

If the average human has 1.3 gallons of blood (~5L) then in a human male, in total you have about 0.000000125 grams of estradiol floating around in the bloodstream. For visual purposes a paper clip is about gram, thus we can’t even wrap our minds around the minuteness of this number. This math may also give you an appreciation for the imprecision and inaccuracy of a serum estradiol value. YET, estrogen is extremely potent and the estrogen all humans have is vital and it is probably not a good idea to tank it just because.

Here are just a few of the functions of Estrogen.

Decreases RER, carb usage, and LPL activity
Increases sensitivity of HSL and Catechoamines and adipocyte lipolysis.
Decreases insulin sensitivity (ERβ)
Increases insulin sensitivity and mitochondrial biogenesis (ERα)
Antioxidant and protects against mitochondrial stress
Increases glycogen synthase activity and glycogen sparing
Attenuates muscle damage, facilitates repair, and enhances satellite muscle cell proliferation
Increases aldosterone mediated sodium reabsorption and retention
Enhances eNOS production
Drives subcutaneous adipose storage
Lowers core temp
Stimulates appetite
Increases cell proliferation and inhibits apoptosis
Decreases MOA and COMT activity

And for the meatheads out there….

“Muscle hypertrophy and muscle repair cannot occur to any great extent without activation and proliferation of satellite cells, and the rate of repair and hypertrophy is directly correlated to the degree of muscle satellite cell activation and proliferation…Blocking estrogen receptors not only completely negates the augmentation effect of estrogen on post-exercise muscle satellite cell activation and proliferation, it also completely eliminates the ability of muscle satellite cells to respond at all to the exercise/damage stimuli”
– Hackney et al. 2016

The world is never black and white.