Free Testosterone targets for the best Libido

[jacb]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido (“Trough value” – Ie Just before your next testosterone shot).

FT - 155 pg/mL = FT - 16 ng/dl.

Using the tru-t.org Free Testosterone Calculator and my last test SHBG and Albumin results
(36 nMol/L & 4.6 g/dL) I see that a total testosterone value of 521.5 ng/dl would achieve a FT value of 16 ng/dl.

Isn't 521 ng/dl Total Testosterone quite low? Does this make sense or am I missing something?

What do you think about an FT target of 155 pg/ml for libido purposes?

Re his Maximum value of FT - PS 175 pg/ml = FT - 18 ng/dl
Using the same SHBG and Albumin results with FT 18 ng/dl = Total Testosterone of 579 ng/dl.

@Nelson Vergel @Vince

 

[FunkOdyssey]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido (“Trough value” – Ie Just before your next testosterone shot).

FT - 155 pg/mL = FT - 16 ng/dl.

Using the tru-t.org Free Testosterone Calculator and my last test SHBG and Albumin results
(36 nMol/L & 4.6 g/dL) I see that a total testosterone value of 521.5 ng/dl would achieve a FT value of 16 ng/dl.

Isn't 521 ng/dl Total Testosterone quite low? Does this make sense or am I missing something?

What do you think about an FT target of 155 pg/ml for libido purposes?

Re his Maximum value of FT - PS 175 pg/ml = FT - 18 ng/dl
Using the same SHBG and Albumin results with FT 18 ng/dl = Total Testosterone of 579 ng/dl.

@Nelson Vergel @Vince

A more complete account of his recommendations: he is saying that with a dose frequency of every 4-6 days, he likes to see 130-175 pg/ml trough value on the Quest EqD free T test. Each of those details is significant if you want to try reproducing his protocol and results.

My thoughts:

1. He's finding relatively infrequent injections of the longer esters to be optimal for libido, which is consistent with a majority of anecdotes where the effect of different injection frequencies were evaluated.
2. The infrequent injections mean the average and peak levels will be higher than you might think given the trough value.
3. Quest EqD free T usually gives a result somewhat lower than the Vermeulen calculated free T that is the de facto standard, again contributing to levels higher than you might expect based on the value alone.
4. You put all of this together and this "optimal libido protocol" has men spending a majority of the time with a calculated free T in the 20-30 ng/dL range which is consistent with most other TRT-focused practitioners.

Don't use that tru-t calculation -- that is garbage compared to Vermeulen. The Vermeulen calculation with your SHBG and albumin values would require a testosterone of 825 ng/dL to hit 17.5 ng/dL free T. Again though, the Quest EqD test he's looking at will usually return a lower result than this calculation, meaning the Total T you would need to hit 17.5 ng/dL on that test would actually be higher.

 

[Vince]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido (“Trough value” – Ie Just before your next testosterone shot).

FT - 155 pg/mL = FT - 16 ng/dl.

Using the tru-t.org Free Testosterone Calculator and my last test SHBG and Albumin results
(36 nMol/L & 4.6 g/dL) I see that a total testosterone value of 521.5 ng/dl would achieve a FT value of 16 ng/dl.

Isn't 521 ng/dl Total Testosterone quite low? Does this make sense or am I missing something?

What do you think about an FT target of 155 pg/ml for libido purposes?

Re his Maximum value of FT - PS 175 pg/ml = FT - 18 ng/dl
Using the same SHBG and Albumin results with FT 18 ng/dl = Total Testosterone of 579 ng/dl.

@Nelson Vergel @Vince

I've always had/have a strong libido no matter what my T level was.

 

[madman]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido (“Trough value” – Ie Just before your next testosterone shot).

FT - 155 pg/mL = FT - 16 ng/dl.

Using the tru-t.org Free Testosterone Calculator and my last test SHBG and Albumin results
(36 nMol/L & 4.6 g/dL) I see that a total testosterone value of 521.5 ng/dl would achieve a FT value of 16 ng/dl.

Isn't 521 ng/dl Total Testosterone quite low? Does this make sense or am I missing something?

What do you think about an FT target of 155 pg/ml for libido purposes?

Re his Maximum value of FT - PS 175 pg/ml = FT - 18 ng/dl
Using the same SHBG and Albumin results with FT 18 ng/dl = Total Testosterone of 579 ng/dl.

@Nelson Vergel @Vince

As I have stated in previous posts no one should be using/relying upon the TruT calculator as it is still in development/needs further validation.

*This Phase IIB proposal aims to continue the development of the TruTTM algorithm by validating it in common conditions characterized by altered estradiol (E2), T, and SHBG concentrations and incorporating the interaction of E2 with T for wider commercial adoption in women in whom E2 levels vary greatly across the menstrual cycle and in TGD population




Everyone should be testing their FT using what would be considered the most accurate assays such as the gold standard Equilibrium Dialysis or Equilibrium Ultrafiltration especially in cases of altered SHBG.

If you do not have access to such assays, highly doubtful if you live in the US then you would need to use/rely upon the linear law-of-mass action cFTV.

Keep in mind as of now cFTV tends to overestimate slightly when compared against a standardized Equilibrium Dialysis assay.

There is no so called optimal trough FT for the best libido!

If anything you should be aiming for a healthy trough FT.

A healthy trough FT based off a standardized ED assay would be around 16-31 ng/dL.

More importantly you need keep the injection frequency/peak--->trough in mind as there is a world of difference between one hitting a high trough FT injecting once weekly vs daily or EOD!

Even than it is not a given that having a healthy/high FT will result in having a good/strong sex drive as libido let alone ED are multifactorial.

Testosterone is only one piece of the puzzle.

Also need to keep in mind that running too high a trough FT level can be just as bad in many ways as running too low a level especially when it comes to libido/erectile function and mood!

Calculate Free Testosterone with TruT by FPT

Labcorp Direct FT No, see above. The converted /adjusted FT direct is lower than dialysis tests. But still much closer to ED results than the "piss poor" TruT calculator. 10% off cFTv will typically get you quite close to dialysis. Note my SHBG has been cut roughly in half since starting...

www.excelmale.com

TruTTM (v2.0) algorithm

ABSTRACT

Background: Measurement of free testosterone (T) concentrations is indicated in the diagnosis of androgen disorders, including hypogonadism in men; hirsutism, polycystic ovary syndrome (PCOS), and androgenic alopecia in women; pubertal disorders in boys and management of gender-affirming hormone therapies for transgender and gender diverse (TGD) persons. This Phase IIB proposal aims to continue the development of the TruTTM algorithm by validating it in common conditions characterized by altered estradiol (E2), T, and SHBG concentrations and incorporating the interaction of E2 with T for wider commercial adoption in women in whom E2 levels vary greatly across the menstrual cycle and in TGD population.

Approach: This application follows the FDA’s published “Guidance for Industry: Bioanalytical Method Validation”.

The essential parameters to determine the acceptability of a bioanalytical method include its technical performance (accuracy, precision, sensitivity, selectivity, stability, and matrix effects).

Reference ranges should be determined in appropriate human samples.

The analytical method should be validated for the intended use (e.g., determination in conditions of intended use, such as persons with altered E2 and T levels, women with PCOS, TGD persons, etc.).

In studies through the Phase II, we demonstrated that the method has superior performance characteristics and extended the validation of TruTTM algorithm in conditions characterized by altered SHBG concentrations.

*In the proposed Phase IIB studies, we will generate the v2.0 of TruTTM algorithm by incorporating the dynamics of the E2 induced perturbation in free T levels, validate it in men, women, and TGD populations (Aim 1) and deploy HIPAA-compliant, secure integration of the algorithm into electronic medical records (EMR) workflow

*(Aim 2). Future Directions and Commercialization potential: The phase IIB program will enable the pilot commercial deployment of a HIPAA-compliant (FDA registered) platform for commercializing the TruTTM (v2.0) algorithm embedded into electronic medical record (EMR) for wider clinical adoption.

These studies will improve clinical care and advance our fundamental understanding of dynamic regulation of T bioavailability in diverse populations including unrepresented sexual and gender minorities

 

[t_spacemonkey]

my free T runs 35ng/dl low - 80ng/dl high. (24h variation). got blood work.
libido high. but also doing high doses HCG. 3x1000IU minimum

 

[jacb]

Thank you FunkOdyssey for your well-considered reply regarding FT and Libido.

You are quite correct the Anabolic Doc did talk of dose frequency of every 4-6 days. I appreciate that would give a larger peak/trough swing than my every other day protocol.

I don’t know what ester he was advocating. I use a medium term ester, Cypionate.

The Anabolic Doc used a Quest (Quest Diagnostics) EqD (equilibrium dialysis) Free Testosterone test. I don’t have access to that test. You say that the Quest EqD FT test usually gives a result somewhat lower than the Vermeulen calculated Free Testosterone (cFT)

The Free testosterone test available to me is an “electrochemiluminescence immunoassay (ECLIA) competition principle test”. I believe therefore, that I am advised to use a cFT for titrating purposes.

My last lab results were:

Total Testosterone: 1015 ng/dL
SHBG: 36 nMol/L
Albumin: 4.6 g/dL
Free Testosterone (ECLIA) 24 ng/dL

Calculated Free Testosterone (cFT)

• FT Calculator Based on Dr Alex Vermeulen Calculations: 22.43 Nu/dL
• University Hospital of Ghent: 22.6 ng/dL
• Tru-T: 33.82 ng/dL

The Tru-T result is obviously VERY different.

You also said “You put all of this together and this "Optimal Libido Protocol" has men spending a majority of the time with a cFT in the 20-30 ng/dL range which is consistent with most other TRT-focused practitioners.

I have therefore run both the Anabolic Doc’s recommendations (130, 155, 175 pg/mL = 13.0, 15.5, 17.5 ng/dL) and your recommendations (20 ng/dL & 30 ng/dL) through the Vermeulen based calculator to see what value Total Testosterone it gives. I have also shown my current values.

SHBG - g/dL​	4.6​	4.6​	4.6​	4.6​	4.6​	4.6​	​
Albumin – nMol/L​	36​	36​	36​	36​	36​	36​	​
cFT – ng/dL​	13​	15.5​	17.5​	20​	22.43​	30​	​
Total Testosterone - ng/dL​	648​	751​	830​	926​	1,015​	1,280​	​

My Points:



1. My Libido at 22.4 ng/dL, is I would say “So/So”, certainly sub optimal.

2. Even with Dr Alex Vermeulen Calculations, the Anabolic Doc is suggesting a FT significantly below your recommendations for Libido. I appreciate that it takes a lot more than FT alone to sort out Libido.

3. My dilemma … increase or decrease my FT? I think I will titrate down since my intent is TRT, not Gym style gains and at 1015 ng/dL (Trough) my TT is I believe, too high.

Rgds.

PS I did find a paper put out by Melbourne Pathology which explains a bit more about the Vermeulen calculation background. See attached.

 

[jacb]

A healthy trough FT based off a standardized ED assay would be around 16-31 ng/dL.

Thanks Madman

FT values of 16 to 31 ng/dL, in my case gives a Total Testosterone range of 771 to 1331 ng/dL when using the Vermeulen calculator.

Quite a wide range to work with when one is trying to use FT as a factor in finding one’s optimal protocol.

 

[jacb]

I've always had/have a strong libido no matter what my T level was.

Thanks Vince, but if that's true, you rather destroy the entire thought process behind the Anabolic Doc's video.

Within what bounds have you kept you T Levels and suffered no libido consequences?

 

[Vince]

Thanks Vince, but if that's true, you rather destroy the entire thought process behind the Anabolic Doc's video.

Within what bounds have you kept you T Levels and suffered no libido consequences?

I guess my T level never got low enough to affect my libido. What my low T did cause was brain fog. Sometimes I forget how bad I felt before I started TRT.

 

[seppuku]

I've always had/have a strong libido no matter what my T level was.

Same - when my total t was at the bottom of the 200's, my libido was still very high

 

[FunkOdyssey]

Thank you FunkOdyssey for your well-considered reply regarding FT and Libido.

You are quite correct the Anabolic Doc did talk of dose frequency of every 4-6 days. I appreciate that would give a larger peak/trough swing than my every other day protocol.

I don’t know what ester he was advocating. I use a medium term ester, Cypionate.

The Anabolic Doc used a Quest (Quest Diagnostics) EqD (equilibrium dialysis) Free Testosterone test. I don’t have access to that test. You say that the Quest EqD FT test usually gives a result somewhat lower than the Vermeulen calculated Free Testosterone (cFT)

The Free testosterone test available to me is an “electrochemiluminescence immunoassay (ECLIA) competition principle test”. I believe therefore, that I am advised to use a cFT for titrating purposes.

My last lab results were:

Total Testosterone: 1015 ng/dL
SHBG: 36 nMol/L
Albumin: 4.6 g/dL
Free Testosterone (ECLIA) 24 ng/dL

Calculated Free Testosterone (cFT)

• FT Calculator Based on Dr Alex Vermeulen Calculations: 22.43 Nu/dL
• University Hospital of Ghent: 22.6 ng/dL
• Tru-T: 33.82 ng/dL

The Tru-T result is obviously VERY different.

You also said “You put all of this together and this "Optimal Libido Protocol" has men spending a majority of the time with a cFT in the 20-30 ng/dL range which is consistent with most other TRT-focused practitioners.

I have therefore run both the Anabolic Doc’s recommendations (130, 155, 175 pg/mL = 13.0, 15.5, 17.5 ng/dL) and your recommendations (20 ng/dL & 30 ng/dL) through the Vermeulen based calculator to see what value Total Testosterone it gives. I have also shown my current values.

SHBG - g/dL​	4.6​	4.6​	4.6​	4.6​	4.6​	4.6​	​
Albumin – nMol/L​	36​	36​	36​	36​	36​	36​	​
cFT – ng/dL​	13​	15.5​	17.5​	20​	22.43​	30​	​
Total Testosterone - ng/dL​	648​	751​	830​	926​	1,015​	1,280​	​

My Points:





1. My Libido at 22.4 ng/dL, is I would say “So/So”, certainly sub optimal.

2. Even with Dr Alex Vermeulen Calculations, the Anabolic Doc is suggesting a FT significantly below your recommendations for Libido. I appreciate that it takes a lot more than FT alone to sort out Libido.

3. My dilemma … increase or decrease my FT? I think I will titrate down since my intent is TRT, not Gym style gains and at 1015 ng/dL (Trough) my TT is I believe, too high.

Rgds.

PS I did find a paper put out by Melbourne Pathology which explains a bit more about the Vermeulen calculation background. See attached.

You are leading yourself astray by comparing your EOD trough to Anabolic Doc's 4-6 day trough. If you kept your weekly dosage the same, and changed your frequency to every 5 days for example, your trough free T would drop significantly and would almost certainly fall within 130 - 175 pg/ml on a Quest EqD test. It might even be on the lower end of that range.

So, you are already in the ballpark with your levels and your dosage. If you want to make a protocol adjustment that has a good chance to improve libido, I would try injecting less frequently. No one knows for sure why that works, but it often does.

 

[Systemlord]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido

Optimal for who?

One number for everyone?

 

[jacb]

Optimal for who?

One number for everyone?

Systemlord

The Anabolic Doc talks about his patients reporting good libido in a Free Testosterone range 130/175 ng/dL. It is not a case of one number for all, he is merely reporting a range that has worked for many.

 

[madman]

Thank you FunkOdyssey for your well-considered reply regarding FT and Libido.

You are quite correct the Anabolic Doc did talk of dose frequency of every 4-6 days. I appreciate that would give a larger peak/trough swing than my every other day protocol.

I don’t know what ester he was advocating. I use a medium term ester, Cypionate.

The Anabolic Doc used a Quest (Quest Diagnostics) EqD (equilibrium dialysis) Free Testosterone test. I don’t have access to that test. You say that the Quest EqD FT test usually gives a result somewhat lower than the Vermeulen calculated Free Testosterone (cFT)

The Free testosterone test available to me is an “electrochemiluminescence immunoassay (ECLIA) competition principle test”. I believe therefore, that I am advised to use a cFT for titrating purposes.

My last lab results were:

Total Testosterone: 1015 ng/dL
SHBG: 36 nMol/L
Albumin: 4.6 g/dL
Free Testosterone (ECLIA) 24 ng/dL

Calculated Free Testosterone (cFT)

• FT Calculator Based on Dr Alex Vermeulen Calculations: 22.43 Nu/dL
• University Hospital of Ghent: 22.6 ng/dL
• Tru-T: 33.82 ng/dL

The Tru-T result is obviously VERY different.

You also said “You put all of this together and this "Optimal Libido Protocol" has men spending a majority of the time with a cFT in the 20-30 ng/dL range which is consistent with most other TRT-focused practitioners.

I have therefore run both the Anabolic Doc’s recommendations (130, 155, 175 pg/mL = 13.0, 15.5, 17.5 ng/dL) and your recommendations (20 ng/dL & 30 ng/dL) through the Vermeulen based calculator to see what value Total Testosterone it gives. I have also shown my current values.

SHBG - g/dL​	4.6​	4.6​	4.6​	4.6​	4.6​	4.6​	​
Albumin – nMol/L​	36​	36​	36​	36​	36​	36​	​
cFT – ng/dL​	13​	15.5​	17.5​	20​	22.43​	30​	​
Total Testosterone - ng/dL​	648​	751​	830​	926​	1,015​	1,280​	​

My Points:






1. My Libido at 22.4 ng/dL, is I would say “So/So”, certainly sub optimal.

2. Even with Dr Alex Vermeulen Calculations, the Anabolic Doc is suggesting a FT significantly below your recommendations for Libido. I appreciate that it takes a lot more than FT alone to sort out Libido.

3. My dilemma … increase or decrease my FT? I think I will titrate down since my intent is TRT, not Gym style gains and at 1015 ng/dL (Trough) my TT is I believe, too high.

Rgds.

PS I did find a paper put out by Melbourne Pathology which explains a bit more about the Vermeulen calculation background. See attached.

Even if you never had your FT tested it is a given with a whopping trough TT >1000 ng/dL and normal SHBG that your FT would be high!

Most healthy young males would be hitting a short-lived peak FT of 13-15 ng/dL based on (cFTV) and if it was tested using Quests ED assay or a standardized ED assay it would most likely be slightly lower.

Your trough cFTV 22.4 ng/dL is high and well over were a healthy young male would be sitting and that is at their peak (highest point during the day) meaning early AM!

Their troughs would be 20-25% lower.

As I have stated previously as of now cFTV tends to overestimate when compared to a standardized gold standard ED assay.

If you had your trough FT tested using Quests ED assay (most accurate) it may very well come back the same or slightly lower.

Also keep in mind that Quest's let alone any of the other labs Equilibrium Dialysis or Equilibrium Ultrafiltration assays are not standardized!

Top it of that there is no harmonized reference range to boot!

Yes, many tend to aim for higher-end troughs but again you need to pay attention to your injection frequency as there will be a big difference in peak-->trough injecting once weekly vs daily/EOD!

Even when injecting twice weekly there will still be a noticeable difference in peak--->trough especially when injecting strictly IM.

Highly doubtful pushing your trough FT even higher will have your libido in overdrive.

If anything you may see a temporary boost as hormones are in flux during the weeks leading up until blood levels have stabilized (4-6 weeks TC/TE).

Unfortunately for many this is short-lived as the body will eventually adapt to its new set-point and for many libido tends to wane more into what would be considered normal/healthy.

Again having a healthy FT is only one piece of the puzzle as libido let alone ED are multifactorial.

Do not get caught up on that more T is better mentality especially when it comes to libido/erectile function!

Everyone wasting their lives on these so called men's health forums are brainwashed by that more T is better mentality.

You know that I need to be hitting a trough TT >1000 ng/dL with a sky-high trough FT to boot!

LMFAO!

Getting quality sleep, minimizing stress (physical/mental), following a healthy diet, exercising/staying active, improving overall vascular health will have a far bigger impact than jacking up your trough FT!

 

[madman]

In the Anabolic Doc’s Video (minute 1:50) he says that a Free Testosterone target of 155 pg/ml is optimum for Libido (“Trough value” – Ie Just before your next testosterone shot).

FT - 155 pg/mL = FT - 16 ng/dl.

Using the tru-t.org Free Testosterone Calculator and my last test SHBG and Albumin results
(36 nMol/L & 4.6 g/dL) I see that a total testosterone value of 521.5 ng/dl would achieve a FT value of 16 ng/dl.

Isn't 521 ng/dl Total Testosterone quite low? Does this make sense or am I missing something?

What do you think about an FT target of 155 pg/ml for libido purposes?

Re his Maximum value of FT - PS 175 pg/ml = FT - 18 ng/dl
Using the same SHBG and Albumin results with FT 18 ng/dl = Total Testosterone of 579 ng/dl.

@Nelson Vergel @Vince

Again show me a natty healthy young male with a TT 1000+ ng/dL let alone 1500+ ng/dL with normal let alone low SHBG?

LMFAO!

 

[jacb]

Thanks Madman
Frankly I was amazed by my high T result.
At the time I was taking 114 mg Testosterone Cypionate per week.
32.5 mg EOD (0.13mL - 250mg/1mL) - IM
I was also taking 440 iu hCG IM, concurrently, with every other Testosterone shot.
The results seemed to me to be anomaly high.
However I have reduced my weekly Testosterone to 105 mg and will retest in about six weeks time.

 

[Nelson Vergel]

Best libido: Good sleep + well-managed stress + TT>400 ng/dL + FT at least 2% of TT + good Thyroid function + No pain + enough estradiol, etc

No such a thing as "best free testosterone" for libido. It's just a part of the equation.

 

[jacb]

Thanks for that Nelson

As a matter of interest how do you calculate % cFT ?

Some say that Total Testosterone numbers should not be chased ... others say that Free Testosterone values gives a better picture of what's going on. But even with the common FT ranges, as shown by this thread, the values (min/max) are very far apart.

Sometimes it seem like we should "lead the perfect life" and "try everything" (TRT wise) and note down what works. No wonder that working out what works best can take years and even then, changes will be needed as we age.

I suppose my intent with this discussion, following the Anabolic Doc's video was to find a starting point for cFT titrating when on TRT. Libido isn't everything, but it is a large part of feeling good for many men.

 

[Cyclingislife]

My experience is The anabolic doc knows what he’s talking about. I did a consultation with him early on, it’s expensive but it was the best money I spent. Once u learn his background, He may have the most experience in this field.He set me on the best path. You have to look at all your markers. One of the best tips he gave me is to keep a daily journal with your dose, vitamin info & most importantly how you feel. I also track sex drive, morning wood & keep my labs in the log. I just use a small notebook. This is the cornerstone to dialing in your protocol. He also told me you will have to experiment to dial yourself in but don’t chase numbers, chase how you FEEL. It works. Plus you can look back at your log & see patterns, etc. From my experience I have found the upper level of Free T 150-180 is where my sweet spot is.

 

[Ozzieville]

I have the opposite issue of Jacb: on 100 mg weekly of T cypionate (divided into 2 weekly doses), my recent (Jan. 2024) Labcorp results show very high T, but rather low free T:

TOTAL TESTOSTERONE: >1500 NG/DL
FREE T: 11.5 (DIRECT)

SHBG wasn't measured on this test, but I assume it's high, thus suppressing free T. I've started taking 10 mg of boron daily in the hope of lowering SHBG and increasing free T.

My libido is OK, but could use a boost.

Any other suggestions welcome!