Determining optimal Free T value

[xqfq]

What is the problem here?

People need to understand the newer research regarding SHBG:T binding and the impact it has on FT levels.

Equilibrium Dialysis is the gold standard when it comes to testing FT.

Unless one is testing FT using Equilibrium Dialysis or Ultrafiltration or using the newer calculated TruT method (which has been shown to be on par with results obtained by Equilibrium Dialysis).....than you truly have no idea where your FT levels sit.

It has been shown over and over that the direct immunoassay (which most rely on) is inaccurate let alone no longer recommended by the Endocrine Society.

Many also use the (cFTV) Vermeulen which has been shown to grossly underestimate FT levels.

If you want to go on and use the other inferior testing methods so be it if it floats your boat @VinceCarter!

LOL.....unfortunately the cut/paste is needed to drive the important points home in those with the thick headed noggins.

Again we can all just sit here and say numbers are just numbers and how you feel overall is what truly matters but the simple fact of the matter is that not only is lab work critical to see how said protocol (dose of T/injection frequency) effects ones TT/FT/e2/DHT levels and overall blood markers but what needs to be stressed is using accurate testing methods to truly know where your levels sit as it can make or break a protocol and save many grief in the long run.

You very well know that many are running FT levels much higher than they think (due to relying on inaccurate testing methods) let alone need.

Of course treating symptoms is what truly matters but one still needs to know where hormone levels sit on such protocol as if we just base it off the "I feel best" nonsense than many men will end up running higher TT/FT (as in well over the reference range) levels than they truly need.

One can easily end up saying I feel best on 200 mg/week.....than it becomes I feel best on 300mg/week and so on.....we are on trt here.....replacement doses of testosterone.....most running these higher doses as in 250+mg/week are claiming trt when in fact their TT/FT levels are well into the supra-physiological range.

If one chooses to run such high levels on trt so be it......but the truth of the matter is most would never need levels this high to benefit from testosterone replacement therapy.

To make matters worse if people on here took the time to understand the newer research regarding SHBG:T binding than they would understand that even if one has higher SHBG very high TT levels as once thought are not needed to achieve a healthy FT level.

Think of how many men are running very high TT thinking that there FT is at a healthy level when in fact it is a lot higher than they think due to relying on piss poor FT testing methods.....all this can be resolved by simply using the newer calculated TruT method which uses a model which is based off the newer understanding of SHBG:T binding.

While this Tru-T method may be more accurate than previous calculated methods for the majority of people, it's still a proxy model and may not reflect reality. For instance, I've learned that SHBG <-> androgen binding affinity can differ between individuals, e.g. some people could have more or less "sticky" SHBG than others.

An example that may drive this home: magnesium changes the binding affinity of T to SHBG-- Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach. - PubMed - NCBI. This is complicated stuff!

 

[Gman86]

While this Tru-T method may be more accurate than previous calculated methods for the majority of people, it's still a proxy model and may not reflect reality. For instance, I've learned that SHBG <-> androgen binding affinity can differ between individuals, e.g. some people could have more or less "sticky" SHBG than others.

An example that may drive this home: magnesium changes the binding affinity of T to SHBG-- Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach. - PubMed - NCBI. This is complicated stuff!

Oh god, madman isn’t gonna like this opinion lol. But i’d have to agree, I still personally feel everyone’s SHBG binds at different rates. I could be wrong on this, but all my experience and research currently leads me to believe that some have stickier SHBG than others. So until it’s conclusively proven otherwise, that’s where I currently stand on it. So it makes it hard for me to 100% trust free t calculators. I want to trust them, but I just don’t think everyone’s SHBG acts the same. Mine, for whatever reason, appears much much stickier than most.

 

[madman]

While this Tru-T method may be (IS) more accurate than previous calculated methods for the majority of people, it's still a proxy model and may not reflect reality. For instance, I've learned that SHBG <-> androgen binding affinity can differ between individuals, e.g. some people could have more or less "sticky" SHBG than others.

An example that may drive this home: magnesium changes the binding affinity of T to SHBG-- Magnesium effect on testosterone-SHBG association studied by a novel molecular chromatography approach. - PubMed - NCBI. This is complicated stuff!

Gman's Test Prop Labs




TruT model: 98% of caucasians (wild type SHBG)

[0325]*The current algorithm and the experimental data reported here were generated using wild type SHBG which is present in nearly 98% of Caucasians. Genome wide association studies have revealed several SHBG polymorphisms, two of which have been reported to affect testosterone binding to SHBG (28). Therefore, in future, the algorithms may include a term for the SHBG genotype.

 

[madman]

Oh god, madman isn’t gonna like this opinion lol. But i’d have to agree, I still personally feel everyone’s SHBG binds at different rates. I could be wrong on this, but all my experience and research currently leads me to believe that some have stickier SHBG than others. So until it’s conclusively proven otherwise, that’s where I currently stand on it. So it makes it hard for me to 100% trust free t calculators. I want to trust them, but I just don’t think everyone’s SHBG acts the same. Mine, for whatever reason, appears much much stickier than most.

Really?

Equilibrium Dialysis is considered the gold standard when testing FT.....period!

The newer TruT calculated method is on par with results obtained by Equilibrium Dialysis.

If one wants to doubt the newer TruT calculated method....than simply get your FT tested using Equilibrium Dialysis or Ultrafiltration.

Forget basing your FT off inaccurate testing methods such as the piss poor direct immunoassay or analog tracer.....let alone the linear law-of-mass action models/equations which have been shown to grossly underestimate FT levels when compared to results obtained by the gold standard Equilibrium Dialysis.

I am not buying into this stickier than others SHBG affecting FT levels drastically!

 

[xqfq]

Gman's Test Prop Labs




TruT model: 98% of caucasians (wild type SHBG)

[0325]*The current algorithm and the experimental data reported here were generated using wild type SHBG which is present in nearly 98% of Caucasians. Genome wide association studies have revealed several SHBG polymorphisms, two of which have been reported to affect testosterone binding to SHBG (28). Therefore, in future, the algorithms may include a term for the SHBG genotype.









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So it sounds like there's not much genetic variation in terms of SHBG types. But what if someone was mega-dosing magnesium, for instance? Wouldn't that, based on the above link, cause free T levels to increase, total T to decrease, and SHBG to remain the same?

 

[Gman86]

Really?

Equilibrium Dialysis is considered the gold standard when testing FT.....period!

The newer TruT calculated method is on par with results obtained by Equilibrium Dialysis.

If one wants to doubt the newer TruT calculated method....than simply get your FT tested using Equilibrium Dialysis or Ultrafiltration.

Forget basing your FT off inaccurate testing methods such as the piss poor direct immunoassay or analog tracer.....let alone the linear law-of-mass action models/equations which have been shown to grossly underestimate FT levels when compared to results obtained by the gold standard Equilibrium Dialysis.

I am not buying into this stickier than others SHBG affecting FT levels drastically!

I honestly am not sure. I wish we knew for certain. I just know that I’ve compared so many guy’s labs with similar total T and SHBG levels, and they ended up having pretty drastically different direct free T levels some of the time. I’ve also found a guy here that had the exact same SHBG and exact same total t as me, and we both just happened to use quest for the labs, so we had the same free T test done. And his free at was insanely higher than mine. Almost double. Could of been a lab error obv, but just all my research, and lab comparisons, lead me to believe there’s at least a possibility that SHBG can in fact be “stickier” in some, and less “sticky” in others. You absolutely could be right madman, and maybe there’s no such thing, but I just need a little more convincing evidence before I fully believe that everyone’s SHBG is basically the same, in regards to binding affinity.

 

[madman]

@Systemlord


Hold onto this tight.....

Still trying to convince yourself that TT 1500+ are needed to achieve a healthy FT even with high SHBG?

I honestly am not sure. I wish we knew for certain. I just know that I’ve compared so many guy’s labs with similar total T and SHBG levels, and they ended up having pretty drastically different direct free T levels some of the time. I’ve also found a guy here that had the exact same SHBG and exact same total t as me, and we both just happened to use quest for the labs, so we had the same free T test done. And his free at was insanely higher than mine. Almost double. Could of been a lab error obv, but just all my research, and lab comparisons, lead me to believe there’s at least a possibility that SHBG can in fact be “stickier” in some, and less “sticky” in others. You absolutely could be right madman, and maybe there’s no such thing, but I just need a little more convincing evidence before I fully believe that everyone’s SHBG is basically the same, in regards to binding affinity.

The direct immunoassay is inaccurate and no longer recommended by the Endocrine Society!

Let alone make sure you understand that in cases of men with very low or high SHBG accurate testing methods Equilibrium Dialysis or Ultrafiltration and the newer TruT calculated method (which again most should be using) are critical to truly know where your FT level sits.

Everyone can keep going round and round pissing against the wall regarding FT seeing as they persist to rely on inaccurate testing methods.....so be it.





Calculate free testosterone with TruT by FPT

If you want to ignore what is clearly in front of you than to each his own....but trust me it is just a matter of time before..... "commercialization of the TruTTM algorithm using a HIPAA compliant infrastructure for its clinical adoption" becomes available.


"it will also enable the development of a HIPAA compliant platform that can be embedded into electronic medical record for wider clinical adoption and for improving clinical care "

 

[madman]

I have given everyone on here a heads up in advance.....take it or leave it!

 

[madman]

Everyone needs to read this over and over until it sinks in!

@Vince Carter/@Systemlord- you guys kissing cousins by any chance?





Regarding the understanding of the newer research on SHBG:T binding!

Straight to the point:


[0387] Relation between Percent FT with Total Testosterone and SHBG. Intra-dimer complex allostery suggests that SHBG can regulate FT fraction over a wide range of total testosterone concentrations without getting saturated. Indeed, it was found that percent FT calculated using the new model changed very modestly over a wide range of total testosterone concentrations. In contrast, the Vermeulen's equation suggests a negative relation between percent FT and total testosterone. Furthermore, as SHBG concentrations increase, percent FT calculated using our new model shows only a modest decline in contrast to the marked decline in percent FT calculated using Vermeulen's equation.

 

[fifty]

Or people could just get the ultrafiltration testosterone test from discountedlabs for $99. Way more accurate.

 

[fifty]

Sticky shbg just means your labs are wrong.

 

[Gman86]

So I commented on a YouTube video, asking what lab, or free T calculator Dr. Nichol’s uses to test free T, and this was his personal response.

“We use an ultrafiltration dialysis method to determine total and free testosterone. Although I don’t aim for a particular number I find that most significantly symptomatic men get the most symptom resolution when their Free testosterone is around 30....or more sometimes”

The ultrafiltration dialysis method is obvious a direct measurement, correct? And does anyone know which lab(s) uses this specific method? Thanks.

 

[fifty]

Discountedlabs $99. Labcorp