ExcelMale
Menu
Home
What's new
Latest activity
Forums
New posts
Search forums
What's new
New posts
Latest activity
Videos
Lab Tests
Doctor Finder
Buy Books
About Us
Men’s Health Coaching
Log in
Register
What's new
Search
Search
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Navigation
Install the app
Install
More options
Contact us
Close Menu
Forums
Testosterone Replacement, Low T, HCG, & Beyond
Testosterone Side Effect Management
New hypothesis: Free E2 rant, E2:SHBG ratios, why does no one bother
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Cataceous" data-source="post: 248289" data-attributes="member: 38109"><p>I agree that free estradiol needs greater emphasis. [USER=15043]@Gman86[/USER] posted a ton of his free estradiol data in <a href="https://www.excelmale.com/forum/threads/spreadsheet-for-calculating-free-t-e2.17216/" target="_blank">this thread</a>. They seem to correspond well to values calculated using the immunoassay-based total estradiol tests.</p><p></p><p style="margin-left: 20px"><em>Take two hypothetical individuals with a measured gold standard fT of 25 and an E2 of 60. One has a normal SHBG, one has a low SHBG. ...</em></p><p></p><p>I've used these "twin" experiments to illustrate that in individuals who differ only in their SHBG, total testosterone varies in response to SHBG. There is no pressure on free testosterone to change at the new steady state. You are now making the same mistake I did, which is to assume a fixed total estradiol. In fact estradiol is produced from free testosterone, and in proportion. With free levels proportional to the production rate you end up with free estradiol proportional to free testosterone. Therefore, in twins with different SHBG the level of free estradiol is unchanged, while the level of total estradiol is lower in the twin with lower SHBG.</p><p></p><p>It's true that there are still some subtleties connected to SHBG's role in transporting steroids. I suspect that macroscopically these can be neglected in favor of the law of mass action applied to the free hormone levels. However, they may well be significant in explaining why a twin with low SHBG may not fare as well as a twin with normal SHBG. One hypothesis is that low SHBG impairs androgenic activity more than it does estrogenic activity, even when free hormone levels are the same.</p></blockquote><p></p>
[QUOTE="Cataceous, post: 248289, member: 38109"] I agree that free estradiol needs greater emphasis. [USER=15043]@Gman86[/USER] posted a ton of his free estradiol data in [URL='https://www.excelmale.com/forum/threads/spreadsheet-for-calculating-free-t-e2.17216/']this thread[/URL]. They seem to correspond well to values calculated using the immunoassay-based total estradiol tests. [INDENT][I]Take two hypothetical individuals with a measured gold standard fT of 25 and an E2 of 60. One has a normal SHBG, one has a low SHBG. ...[/I][/INDENT] I've used these "twin" experiments to illustrate that in individuals who differ only in their SHBG, total testosterone varies in response to SHBG. There is no pressure on free testosterone to change at the new steady state. You are now making the same mistake I did, which is to assume a fixed total estradiol. In fact estradiol is produced from free testosterone, and in proportion. With free levels proportional to the production rate you end up with free estradiol proportional to free testosterone. Therefore, in twins with different SHBG the level of free estradiol is unchanged, while the level of total estradiol is lower in the twin with lower SHBG. It's true that there are still some subtleties connected to SHBG's role in transporting steroids. I suspect that macroscopically these can be neglected in favor of the law of mass action applied to the free hormone levels. However, they may well be significant in explaining why a twin with low SHBG may not fare as well as a twin with normal SHBG. One hypothesis is that low SHBG impairs androgenic activity more than it does estrogenic activity, even when free hormone levels are the same. [/QUOTE]
Insert quotes…
Verification
Post reply
Share this page
Facebook
Twitter
Reddit
Pinterest
Tumblr
WhatsApp
Email
Share
Link
Sponsors
Forums
Testosterone Replacement, Low T, HCG, & Beyond
Testosterone Side Effect Management
New hypothesis: Free E2 rant, E2:SHBG ratios, why does no one bother
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.
Accept
Learn more…
Top