T3 and estrogen

[yuliyam]

Hello everyone. I have been reading that apparently being slightly overactive may increase breast cancer risk so may I ask please have you heard of this and why does it happen? Is it because T3 increases estrogen? Thank you and I hope you are all well xxx

[Aurealis]

I understand that being undertreated for hypothyroidism raises the risk. Not sure of mechanism but underlines the necessity for optimal levels of treatment. I prefer to listen to the signs and symptoms of under/overtreatment from my body in preference to blood test results. Do you mean overactive or overtreated?

[Angel_of_the_North]

I take T3 only and do not have high oestrogen (according to blood tests). But we are all different.

[Heloise]

Aurealis asks a good question. Is your T3 result over range? But this doesn't mean you are actually using it.

When you are hypothyroid your adrenals are usually overworking. They need more cholesterol to make the critical steroids so are liver makes more and that is good. There is also something about progesterone making more necessary for the adrenals to work. This might make estrogen look higher but I'm not sure. There is estrogen in many foods and the pesticides used on our produce are also estrogen based. Estrogen dominance makes thyroid problems more difficult to treat.

My opinion is that using progesterone cream can be very helpful and it also makes estrogen if needed. Ray Peat is a genius.

raypeat.com/articles/