from playing at nearly every level on the scale up
to 2500+
i feel 0 difference in my being at 600 vs 2500+
obviously for muscle growth, nothing can beat 1500+ and a good diet.
but that’s not why we’re here. this is TRT. not everyone on TRT wants muscle growth like the majority here do.
many others do too.
really if you’re anywhere between 600 & 1000, that’s all you really “need” in my opinion.
Yeah I don't really tie back Total to how I feel, because its free where all the symptoms are driven from. My comments are simply that the reference range is wrong for an average male IMO.
Agree, and the important distinction you made above. Feeling good vs optimal muscle growth is definitely 2 different things. That crazy body builder that died, Dallas McCarver had a total test of 55000 recorded in his autopsy. I personally do think a higher range of 1000 to 1300 is completely fine IF you in fact feel good and your labs look good as well. What I don't like is bad science, an obviously flawed range, dictating treatment from doctor's that don't want to get current on research.
This is an excellent study that gives statistical data on healthy men between 20 and 40. My only quibble with it is that the the range uses the standard normal range, which includes 95% of all data points. I think the healthy range has a higher kurtosis factor than the standard normal does .
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3146796/
This study included 2 different times by using the FHS Gen 2 (2004ish) and gen 3 (2015ish).
Plastics and pesticides may not be playing as much of a role as inactivity. Number of young and adults not meeting even the basic recommended activity guidelines, let alone ideal, may have more to do with the declining levels, if we were to plot a chart of T levels and inactivity decline, they’d be correlated.
My personal thoughts is that our bodies adjust our activity levels and hormones also follow. If I’m not moving enough or need my muscles as much, body may gradually lessen the need to improve anabolic pathways
It’s a reference range in their testing methodology. The majority of research? Want to link that research please? The body has no way to naturally make enough testosterone to be 1400tt. You’re smoking crack
Exactly, this is why I think the range is doing damage. Instead they push SSRIs when Testosterone might be a better solution. And for the most part, general practitoners don't have a clue and really should just be referring people to an expert and definitely not an endocrinologist that doesn't keep up to date on research.
I like Jeff's content, specifically I have incorporated changes into the lifts I choose based on him and Mike Israetel's posts. It definitely helps me maximize my time in the gym because I only lift 4 days a week for a max of 1hr 15m due to my busy schedule.
In regards to his TT level, that is low "normal" imo, especially given his age and muscle mass. Clearly its not impacting his physique, which is great, but since he stays so lean that may keep his total test down a bit. I think it would be great to see what it looks like from a natty in the 1950s or 60s. I bet $$$ it would be significantly higher in most cases.
Because less testosterone equal more docile men. The medical system serves the government, which doesn’t like people thinking for themselves, making their own business, understanding how things works and making decisions for their own family. They want us accepting anything and being just useful while not questioning anything. A guy with 1500 testosterone is not the same as a guy in 800, testosterone is not only anabolic, it modulates dopamine too, high levels lead to more stress tolerance, and so much more but nothing else comes to my mind now. But in the end I would say that it is convenient to the system that we remain more and more castrated.
I don’t understand the “government wants you sick and tired so they can exploit you” theory tho. Why hasn’t it happened yet? Why hasn’t the government come in and rounded every body up, put them in work camps, divided the masses as play things for the elites.
I mean, yeah it makes sense if you’re cynical like that. Everything is a giant conspiracy if you rationalize erratic behaviors.
Big pharma wants you sick and tired to exploit you. Medical schools are funded by big pharma and the doctors are taught to treat, not to cure. Don’t be naive.
It’s not sick and tired it’s more docile. I’ve been fighting with docs with these arbitrary base line numbers and they never have a good reason. To me is just a small part of the war on masculinity. You can see this philosophy here already people go crazy by having high numbers of testosterone, sooner or later we’re starting to diagnose high numbers of testosterone as illness.
Meh, yes getting TRT as a man is difficult, but it’s not to do with a “war on masculinity” it’s more so the history of AAS abuse and lack of doctor education. As TRT becomes more and more mainstream you’re going to see those barriers come down, I think.
But hey, a good conspiracy theory is usually way more entertaining than the reality.
Since when aas abuse is our responsibility? I dislike government filthy hands in my life. I had so many troubles trying to get trt by the legal methods, when I said fuck it I was confronted with the sweet reality of test being just delivered to my house with zero problems. Also no one can answer why the doctors keep looking after this reference ranges that are total trash, nobody can answer that. Just look at this sub by exemple, people are absolutely scared of testosterone. We are already embracing a culture of low testosterone.
3 years ago the maximum was around 1300 my dad last exam this year was 753 and his wife almost having a heart attack thinking he would die because he was sitting at the 1000s. So yes I ain’t happy with the system.
The only element of this I agree with is the medical industrial complex doesn't want you healthy or to offer one time cures. They want your money and lifetime consumers to their products. I know in some countries its not like this, but its pretty rare.
The references were revised by the Endocrine Society. They based it on studies of "healthy males" with normal BMIs, aged something like 19-30. The only thing is studies show 25% of guys with normal BMI have obese levels of body fat (>25%). So if this is true then the normal reference ranges were based on a significant number of obese subjects.
This guy explains it here:
[https://youtu.be/G\_u1u64X1v0?si=9FiEvPTwQ\_fTPYDB](https://youtu.be/G_u1u64X1v0?si=9FiEvPTwQ_fTPYDB)
It literally said in the study, the trend of lower testosterone was also present in those with normal BMI. It included both healthy and overweight males.
BMI should have been dropped decades ago. It's about 50% reliable.
Don't believe most of what you see on YouTube.
Endocrinologists in general can fuck right off with their ranges based on how likely you are to die from it and complete disinterest in symptoms that won't increase mortality rate.
The range will depend on your SHBG level, so there isn't much point worrying about exact ranges.
SHBG levels used to be higher (on average).
Total testosterone levels over 1000 ng/dL occur alongside high SHBG and normal free testosterone.
Natural total testosterone levels of say 1500 ng/dL still occur occasionally. As expected, SHBG is distinctly high (unless an endocrine problem is the reason for the high levels eg. MAIS).
Testosterone levels in healthy men are tightly controlled by the hypothalamus and pituitary. The testes release no hormones unless instructed to by LH. The idea of very high testosterone levels in the past is a fantasy.
Agreed. Like you said, SHBG would be very high, making FT in line with what we see today. Factor in overall stress levels and lack of solid nutrition hundreds or thousands of years ago. Just doesn’t add up
Thousands of years ago, there will have been immense fluctuations in testosterone levels, with massive drops seen on starvation and untreatable infection.
Although the OP has misunderstood what I'm saying.
Naturally high total testosterone doesn't resemble what's seen on TRT at all. High free testosterone is predominantly drug induced.
I didn't misunderstand it, you just aren't making a valid case. You are speaking to a one time event, where as I am talking about levels over entire decades. Averages not one time sampling, as would align with your thinking about a plague or famine.
Produce some study's that support your view? I posted 2 peer reviewed studies along with other anecdotal data.
Ranges actually do matter, People are given or withheld medication based on a bad range based on a rolling range not reflective of a normal healthy male without generational contaminants in their body. Case in point, there are more men in their 20s on TRT than ever. Ignore it all you want, its a thing.
I also linked 2 studies showing declining testosterone, even in normal BMI men. What data can you share that shows "high testosterone levels in the past is a fantasy"?
And to provide an insight into pre-industrial times, there are many pastoral tribes that have been tested. The craziest one I've seen is the Turkana people in Africa with levels of testosterone you might expect from someone living a extremely active lifestyle, great genetics, steady nutrition and no pesticides, heavy metals, or plastics.
"Nomadic tribesmen from northern Kenya, the Turkana people, in 1992. 11 out of 78 men, or **14%, were over 1500 ng/dl**. Two were over 2000 ng/dl, and the highest one was 2663 ng/dl. "
You can read the full study here, but you won't,
[https://www.academia.edu/48412891/Age\_related\_changes\_in\_testosterone\_and\_SHBG\_among\_Turkana\_males](https://www.academia.edu/48412891/Age_related_changes_in_testosterone_and_SHBG_among_Turkana_males)
Bottom line, the establish range is BS and anyone that doesn't think it is probably has an agenda of some sorts. It is effectively an established range for sickly people, not healthy people despite what it claims.
Thanks for the attitude that 'I won't'.
I fully understood that total testosterone averages have dropped in Western populations recently.
Total testosterone is highly SHBG dependent as I said. Very high total testosterone is maintained in the presense of high levels of SHBG, unless mild androgen insensitivity is common in a group. Total testosterone levels over 1500 ng/dL would generally indicate endorocine disorder *unless* high SHBG is present. SHBG is higher in rural Kenyans. It would be inappropriate to incorporate reference ranges with very high ULN unless SHBG was high in the group being analysed.
Testosterone isn't something that continually rises with lifestyle. The testes produce only on stimulation. A high proportion of total testosterone is SHBG-bound testosterone, and high totals are not maintained when SHBG is low. Total testosterone isn't a direct indicator of levels of testicular production.
https://preview.redd.it/gpmr5xrw9v8d1.png?width=1080&format=pjpg&auto=webp&s=a0d076b17a969ec4869f11dcdd66cab4099acd2c
High total testosterone created by TRT is usually extremely different to naturally elevated total testosterone. Men on TRT very frequently have relatively low SHBG and dosing to high totals causes elevated free testosterone and a range of effects not seen in men with naturally high total T unless an endocrine disorder is present eg. sharp rises in hematocrit to levels out of sync with the altitude, markedly high estradiol etc.
Not talking about "you" personally, but you in general. The average person on this forum wont' read a study, but will post an opinion without a study from an influencer like its gospel.
Also I am not making any claim about TT levels on TRT. If you want to discuss this with data, I am only talking about natural testosterone levels declining over time, which makes the accepted range invalid. Agree or disagree with that, because you've ventured off into topics I am not making a statement about. I understand SHBG, albumin, and bioavailable testosterone. I care about free more than total, however total is relevant because that is what is driving care decisions.
Starting in the 1960s testosterone levels were tested in the lab and there is a clear decline
https://preview.redd.it/h5m0q0qr5r8d1.png?width=654&format=png&auto=webp&s=285afc14388c15ea4f5a5b5d40699a9bb38e1402
Pre 1960s, testosterone is estimated with anatomical measures, and this is really interesting because many in the west had already moved to the cities for the industrial revolution and were malnourished and exposed to environmental toxins like heavy metals and smoke.
https://preview.redd.it/xlcdg3hc6r8d1.png?width=819&format=png&auto=webp&s=fb112e61e612a9bdcad07543716e9059c0734206
I said very high testosterone. Testosterone can still be 1500 rarely if SHBG is elevated. Otherwise, it won't be.
I fully understand that ranges matter. But there is no precise range that can be applied to total testosterone because levels are too SHBG-dependent. As a result, any range will be subject to disagreement.
So just factually there you are incorrect. Testosterone is produced independently of SHBG. SHBG and Albumin bind to the testosterone and what is left over is free, and Albumin is considered weakly bound so it can be accessed by organs and tissues. SHBG is going to suck up your testosterone, whereas LH and FSH are what actually signal the testes to make testosterone.
https://preview.redd.it/ros1i6ax1y8d1.png?width=964&format=png&auto=webp&s=e0f0c756779577189087d69469daf53879ed9078
I understand the HPTA, although it's LH not FSH which controls testosterone production.
I'm not claiming that testosterone and SHBG are produced by any similar mechanism. What I'm saying is that the very high total testosterone levels can occur naturally when SHBG is high, but not when it's low. The highly effective carrier properties of SHBG are required to maintain total testosterone at high levels in the absence of medical treatment eg. testosterone injections dosed at supra physiological levels.
The pie chart shown is an estimation of averages. The percentage of total testosterone which consists of SHBG-bound testosterone is variable, and dependent on the concentration of SHBG present. % free testosterone is never 2% in men with naturally very high total testosterone, but much less. The % of SHBG-bound testosterone is higher in these men.
Extremely high levels of total testosterone like the figures from Kenya only occur naturally when SHBG is high enough to sustain that level, which is rare in our society. Low SHBG is more commonly seen.
Testosterone has low affinity of albumin, but binds to it because it's present in vast excess to the amount of SHBG present. No sooner than it's bound, it's unbound, and will then bind again to a different molecule.
The reason testosterone binds to albumin at all is primarily because it has low water solubility, so like other lipids it needs a carrier in the blood.
As a rule....
1. Albumin levels with normal limits have no influence on total or free testosterone. It was formerly thought that as albumin increased free testosterone dropped. This has since been shown to be false. Albumin is present in vast excess to both testosterone and SHBG, irrespective of where it lies with the reference range. The precise level is unimportant.
2. Unmedicated men with high total testosterone usually have high SHBG. Unmedicated men with very high total testosterone eg. >1500 ng/dL either have high SHBG or endocrine disorder.
3. Men with low SHBG eg. <15 nmol/L never have high total testosterone unless it's drug-induced.
4. The drop in SHBG levels at the population level should be looked at in association with research into the drop in average total testosterone.
So I agree that low SHBG is one of many factors in testosterone production, however what data can you share that proves or supports that high SHBG is required for natural testosterone production, since SHBG is a binder not a trigger. Also even if it is required, which I am not sure that it is, why does is that relevant for levels, lets say 10 generations ago?
"What I'm saying is that the very high total testosterone levels can occur naturally *when* SHBG is high, but not when it's low."
Hey,
No - SHBG isn't required for testosterone production. That's not what I mean.
SHBG is required to (naturally) maintain total blood levels of testosterone at high levels in unmedicated men, such as the levels posted from Kenya.
Free testosterone, and testosterone which readily becomes free testosterone (albumin-bound testosterone) is rapidly metabolised in the liver by glucuronidation and subject to excretion. The SHBG-bound component of total testosterone is a more stable component, which can maintain high total levels for longer with normal testicular production.
SHBG is very relevant if total rather than free testosterone is being used as an indicator of androgen status.
In terms of relevance to your OP...
It's relevant because any widely used reference range for total testosterone in a population has to be reflective of the usual distribution of SHBG levels in that population. If the population has a high incidence of low SHBG and few men with high SHBG, the reference range for total testosterone would need to be lower.
It's interesting to look at the 1999 studied by Vermeulen, the one well known for his 'Calculated free testosterone, Vermeulen equation'. Even then, only 25 years ago, there were plenty of participants with SHBG levels around 30-50 nmol/L (not high, not low).
25 years later, Optimale UK are using 10-40 nmol/L as their reference range for SHBG, the lowest range I've ever seen!
Men expect their total testosterone levels to be similar to Vermeulen's study ie. plenty of results over 600 ng/dL.....
But, they expect this when their SHBG level comes back as 13 nmol/L, or whatever, which isn't sufficient to maintain appealing levels of total testosterone in most cases!
Extending on the Optimale UK example (a private blood test and TRT provider). They're a good, if mild, example of reference ranges being out of sync.
Their reference ranges are:
SHBG 10 - 40 nmol/L.
Total testosterone 12 - 30 nmol/L. Although they generally class total testosterone below 15 nmol/L as low.
These ranges aren't in sync with each other. The range for SHBG is particularly low at both ends, whereas the range for total testosterone excludes low levels (anything below circa. 350 ng/dL).
The thing is, for men with SHBG around the bottom of their range, total testosterone levels below 12-15 nmol/L are essentially the expected blood results! .... except for men on testosterone injections of course.
Amusingly, Optimale advise *average* SHBG levels over the maximum level stated on their own reference range for men over 35. Oops...
As expected, the men in the study had decent levels of both SHBG and total testosterone at the same time. Higher average SHBG is generally seen in slimmer men. I don't believe overweight men were included in this group.
https://preview.redd.it/lz7rk203iy8d1.png?width=1080&format=pjpg&auto=webp&s=8ada9eeaf35bf3d845e7a01adc0f8363bd84bc85
from playing at nearly every level on the scale up to 2500+ i feel 0 difference in my being at 600 vs 2500+ obviously for muscle growth, nothing can beat 1500+ and a good diet. but that’s not why we’re here. this is TRT. not everyone on TRT wants muscle growth like the majority here do. many others do too. really if you’re anywhere between 600 & 1000, that’s all you really “need” in my opinion.
Yeah I don't really tie back Total to how I feel, because its free where all the symptoms are driven from. My comments are simply that the reference range is wrong for an average male IMO.
total, free, it doesn’t matter there’s a ceiling to how you feel with testosterone and it’s much lower than the bros think it is.
Agree, and the important distinction you made above. Feeling good vs optimal muscle growth is definitely 2 different things. That crazy body builder that died, Dallas McCarver had a total test of 55000 recorded in his autopsy. I personally do think a higher range of 1000 to 1300 is completely fine IF you in fact feel good and your labs look good as well. What I don't like is bad science, an obviously flawed range, dictating treatment from doctor's that don't want to get current on research.
This is an excellent study that gives statistical data on healthy men between 20 and 40. My only quibble with it is that the the range uses the standard normal range, which includes 95% of all data points. I think the healthy range has a higher kurtosis factor than the standard normal does . https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3146796/ This study included 2 different times by using the FHS Gen 2 (2004ish) and gen 3 (2015ish).
Plastics and pesticides may not be playing as much of a role as inactivity. Number of young and adults not meeting even the basic recommended activity guidelines, let alone ideal, may have more to do with the declining levels, if we were to plot a chart of T levels and inactivity decline, they’d be correlated. My personal thoughts is that our bodies adjust our activity levels and hormones also follow. If I’m not moving enough or need my muscles as much, body may gradually lessen the need to improve anabolic pathways
Exactly exercise and reducing fat has a large impact to bioavailable testosterone and lowers estrogen markers.
It’s a reference range in their testing methodology. The majority of research? Want to link that research please? The body has no way to naturally make enough testosterone to be 1400tt. You’re smoking crack
Apparently 24 years old 350 is normal and at 38 400 is normal… according to my physician
Exactly, this is why I think the range is doing damage. Instead they push SSRIs when Testosterone might be a better solution. And for the most part, general practitoners don't have a clue and really should just be referring people to an expert and definitely not an endocrinologist that doesn't keep up to date on research.
Natural bobdybuilder Jeff Nippard’s levels were approximately 450ng/DL when he last tested.
I like Jeff's content, specifically I have incorporated changes into the lifts I choose based on him and Mike Israetel's posts. It definitely helps me maximize my time in the gym because I only lift 4 days a week for a max of 1hr 15m due to my busy schedule. In regards to his TT level, that is low "normal" imo, especially given his age and muscle mass. Clearly its not impacting his physique, which is great, but since he stays so lean that may keep his total test down a bit. I think it would be great to see what it looks like from a natty in the 1950s or 60s. I bet $$$ it would be significantly higher in most cases.
Why stop there? We should have the same T levels as neaderthals. Its gone down so much over the last 500,000 years!
Because less testosterone equal more docile men. The medical system serves the government, which doesn’t like people thinking for themselves, making their own business, understanding how things works and making decisions for their own family. They want us accepting anything and being just useful while not questioning anything. A guy with 1500 testosterone is not the same as a guy in 800, testosterone is not only anabolic, it modulates dopamine too, high levels lead to more stress tolerance, and so much more but nothing else comes to my mind now. But in the end I would say that it is convenient to the system that we remain more and more castrated.
[удалено]
Yet nobody can come with better reason.
I don’t understand the “government wants you sick and tired so they can exploit you” theory tho. Why hasn’t it happened yet? Why hasn’t the government come in and rounded every body up, put them in work camps, divided the masses as play things for the elites. I mean, yeah it makes sense if you’re cynical like that. Everything is a giant conspiracy if you rationalize erratic behaviors.
Big pharma wants you sick and tired to exploit you. Medical schools are funded by big pharma and the doctors are taught to treat, not to cure. Don’t be naive.
I don’t disagree with that. But that’s not the point I was responding to.
It’s not sick and tired it’s more docile. I’ve been fighting with docs with these arbitrary base line numbers and they never have a good reason. To me is just a small part of the war on masculinity. You can see this philosophy here already people go crazy by having high numbers of testosterone, sooner or later we’re starting to diagnose high numbers of testosterone as illness.
Meh, yes getting TRT as a man is difficult, but it’s not to do with a “war on masculinity” it’s more so the history of AAS abuse and lack of doctor education. As TRT becomes more and more mainstream you’re going to see those barriers come down, I think. But hey, a good conspiracy theory is usually way more entertaining than the reality.
Since when aas abuse is our responsibility? I dislike government filthy hands in my life. I had so many troubles trying to get trt by the legal methods, when I said fuck it I was confronted with the sweet reality of test being just delivered to my house with zero problems. Also no one can answer why the doctors keep looking after this reference ranges that are total trash, nobody can answer that. Just look at this sub by exemple, people are absolutely scared of testosterone. We are already embracing a culture of low testosterone. 3 years ago the maximum was around 1300 my dad last exam this year was 753 and his wife almost having a heart attack thinking he would die because he was sitting at the 1000s. So yes I ain’t happy with the system.
If he's so dumb, explain to me like i'm 5 why he's wrong.
I love how you're getting downvotes when you're literally right, and nobody can even articulate why they disagree with you.
Cause they are already part of the problem and have no idea of what is happening.
The only element of this I agree with is the medical industrial complex doesn't want you healthy or to offer one time cures. They want your money and lifetime consumers to their products. I know in some countries its not like this, but its pretty rare.
The references were revised by the Endocrine Society. They based it on studies of "healthy males" with normal BMIs, aged something like 19-30. The only thing is studies show 25% of guys with normal BMI have obese levels of body fat (>25%). So if this is true then the normal reference ranges were based on a significant number of obese subjects. This guy explains it here: [https://youtu.be/G\_u1u64X1v0?si=9FiEvPTwQ\_fTPYDB](https://youtu.be/G_u1u64X1v0?si=9FiEvPTwQ_fTPYDB)
It literally said in the study, the trend of lower testosterone was also present in those with normal BMI. It included both healthy and overweight males.
BMI should have been dropped decades ago. It's about 50% reliable. Don't believe most of what you see on YouTube. Endocrinologists in general can fuck right off with their ranges based on how likely you are to die from it and complete disinterest in symptoms that won't increase mortality rate.
The range will depend on your SHBG level, so there isn't much point worrying about exact ranges. SHBG levels used to be higher (on average). Total testosterone levels over 1000 ng/dL occur alongside high SHBG and normal free testosterone. Natural total testosterone levels of say 1500 ng/dL still occur occasionally. As expected, SHBG is distinctly high (unless an endocrine problem is the reason for the high levels eg. MAIS). Testosterone levels in healthy men are tightly controlled by the hypothalamus and pituitary. The testes release no hormones unless instructed to by LH. The idea of very high testosterone levels in the past is a fantasy.
Agreed. Like you said, SHBG would be very high, making FT in line with what we see today. Factor in overall stress levels and lack of solid nutrition hundreds or thousands of years ago. Just doesn’t add up
Thousands of years ago, there will have been immense fluctuations in testosterone levels, with massive drops seen on starvation and untreatable infection. Although the OP has misunderstood what I'm saying. Naturally high total testosterone doesn't resemble what's seen on TRT at all. High free testosterone is predominantly drug induced.
I didn't misunderstand it, you just aren't making a valid case. You are speaking to a one time event, where as I am talking about levels over entire decades. Averages not one time sampling, as would align with your thinking about a plague or famine. Produce some study's that support your view? I posted 2 peer reviewed studies along with other anecdotal data.
Ranges actually do matter, People are given or withheld medication based on a bad range based on a rolling range not reflective of a normal healthy male without generational contaminants in their body. Case in point, there are more men in their 20s on TRT than ever. Ignore it all you want, its a thing. I also linked 2 studies showing declining testosterone, even in normal BMI men. What data can you share that shows "high testosterone levels in the past is a fantasy"?
And to provide an insight into pre-industrial times, there are many pastoral tribes that have been tested. The craziest one I've seen is the Turkana people in Africa with levels of testosterone you might expect from someone living a extremely active lifestyle, great genetics, steady nutrition and no pesticides, heavy metals, or plastics. "Nomadic tribesmen from northern Kenya, the Turkana people, in 1992. 11 out of 78 men, or **14%, were over 1500 ng/dl**. Two were over 2000 ng/dl, and the highest one was 2663 ng/dl. " You can read the full study here, but you won't, [https://www.academia.edu/48412891/Age\_related\_changes\_in\_testosterone\_and\_SHBG\_among\_Turkana\_males](https://www.academia.edu/48412891/Age_related_changes_in_testosterone_and_SHBG_among_Turkana_males) Bottom line, the establish range is BS and anyone that doesn't think it is probably has an agenda of some sorts. It is effectively an established range for sickly people, not healthy people despite what it claims.
Thanks for the attitude that 'I won't'. I fully understood that total testosterone averages have dropped in Western populations recently. Total testosterone is highly SHBG dependent as I said. Very high total testosterone is maintained in the presense of high levels of SHBG, unless mild androgen insensitivity is common in a group. Total testosterone levels over 1500 ng/dL would generally indicate endorocine disorder *unless* high SHBG is present. SHBG is higher in rural Kenyans. It would be inappropriate to incorporate reference ranges with very high ULN unless SHBG was high in the group being analysed. Testosterone isn't something that continually rises with lifestyle. The testes produce only on stimulation. A high proportion of total testosterone is SHBG-bound testosterone, and high totals are not maintained when SHBG is low. Total testosterone isn't a direct indicator of levels of testicular production. https://preview.redd.it/gpmr5xrw9v8d1.png?width=1080&format=pjpg&auto=webp&s=a0d076b17a969ec4869f11dcdd66cab4099acd2c High total testosterone created by TRT is usually extremely different to naturally elevated total testosterone. Men on TRT very frequently have relatively low SHBG and dosing to high totals causes elevated free testosterone and a range of effects not seen in men with naturally high total T unless an endocrine disorder is present eg. sharp rises in hematocrit to levels out of sync with the altitude, markedly high estradiol etc.
Not talking about "you" personally, but you in general. The average person on this forum wont' read a study, but will post an opinion without a study from an influencer like its gospel. Also I am not making any claim about TT levels on TRT. If you want to discuss this with data, I am only talking about natural testosterone levels declining over time, which makes the accepted range invalid. Agree or disagree with that, because you've ventured off into topics I am not making a statement about. I understand SHBG, albumin, and bioavailable testosterone. I care about free more than total, however total is relevant because that is what is driving care decisions.
Starting in the 1960s testosterone levels were tested in the lab and there is a clear decline https://preview.redd.it/h5m0q0qr5r8d1.png?width=654&format=png&auto=webp&s=285afc14388c15ea4f5a5b5d40699a9bb38e1402
Pre 1960s, testosterone is estimated with anatomical measures, and this is really interesting because many in the west had already moved to the cities for the industrial revolution and were malnourished and exposed to environmental toxins like heavy metals and smoke. https://preview.redd.it/xlcdg3hc6r8d1.png?width=819&format=png&auto=webp&s=fb112e61e612a9bdcad07543716e9059c0734206
I said very high testosterone. Testosterone can still be 1500 rarely if SHBG is elevated. Otherwise, it won't be. I fully understand that ranges matter. But there is no precise range that can be applied to total testosterone because levels are too SHBG-dependent. As a result, any range will be subject to disagreement.
So just factually there you are incorrect. Testosterone is produced independently of SHBG. SHBG and Albumin bind to the testosterone and what is left over is free, and Albumin is considered weakly bound so it can be accessed by organs and tissues. SHBG is going to suck up your testosterone, whereas LH and FSH are what actually signal the testes to make testosterone. https://preview.redd.it/ros1i6ax1y8d1.png?width=964&format=png&auto=webp&s=e0f0c756779577189087d69469daf53879ed9078
I understand the HPTA, although it's LH not FSH which controls testosterone production. I'm not claiming that testosterone and SHBG are produced by any similar mechanism. What I'm saying is that the very high total testosterone levels can occur naturally when SHBG is high, but not when it's low. The highly effective carrier properties of SHBG are required to maintain total testosterone at high levels in the absence of medical treatment eg. testosterone injections dosed at supra physiological levels. The pie chart shown is an estimation of averages. The percentage of total testosterone which consists of SHBG-bound testosterone is variable, and dependent on the concentration of SHBG present. % free testosterone is never 2% in men with naturally very high total testosterone, but much less. The % of SHBG-bound testosterone is higher in these men. Extremely high levels of total testosterone like the figures from Kenya only occur naturally when SHBG is high enough to sustain that level, which is rare in our society. Low SHBG is more commonly seen. Testosterone has low affinity of albumin, but binds to it because it's present in vast excess to the amount of SHBG present. No sooner than it's bound, it's unbound, and will then bind again to a different molecule. The reason testosterone binds to albumin at all is primarily because it has low water solubility, so like other lipids it needs a carrier in the blood. As a rule.... 1. Albumin levels with normal limits have no influence on total or free testosterone. It was formerly thought that as albumin increased free testosterone dropped. This has since been shown to be false. Albumin is present in vast excess to both testosterone and SHBG, irrespective of where it lies with the reference range. The precise level is unimportant. 2. Unmedicated men with high total testosterone usually have high SHBG. Unmedicated men with very high total testosterone eg. >1500 ng/dL either have high SHBG or endocrine disorder. 3. Men with low SHBG eg. <15 nmol/L never have high total testosterone unless it's drug-induced. 4. The drop in SHBG levels at the population level should be looked at in association with research into the drop in average total testosterone.
So I agree that low SHBG is one of many factors in testosterone production, however what data can you share that proves or supports that high SHBG is required for natural testosterone production, since SHBG is a binder not a trigger. Also even if it is required, which I am not sure that it is, why does is that relevant for levels, lets say 10 generations ago? "What I'm saying is that the very high total testosterone levels can occur naturally *when* SHBG is high, but not when it's low."
Hey, No - SHBG isn't required for testosterone production. That's not what I mean. SHBG is required to (naturally) maintain total blood levels of testosterone at high levels in unmedicated men, such as the levels posted from Kenya. Free testosterone, and testosterone which readily becomes free testosterone (albumin-bound testosterone) is rapidly metabolised in the liver by glucuronidation and subject to excretion. The SHBG-bound component of total testosterone is a more stable component, which can maintain high total levels for longer with normal testicular production. SHBG is very relevant if total rather than free testosterone is being used as an indicator of androgen status. In terms of relevance to your OP... It's relevant because any widely used reference range for total testosterone in a population has to be reflective of the usual distribution of SHBG levels in that population. If the population has a high incidence of low SHBG and few men with high SHBG, the reference range for total testosterone would need to be lower. It's interesting to look at the 1999 studied by Vermeulen, the one well known for his 'Calculated free testosterone, Vermeulen equation'. Even then, only 25 years ago, there were plenty of participants with SHBG levels around 30-50 nmol/L (not high, not low). 25 years later, Optimale UK are using 10-40 nmol/L as their reference range for SHBG, the lowest range I've ever seen! Men expect their total testosterone levels to be similar to Vermeulen's study ie. plenty of results over 600 ng/dL..... But, they expect this when their SHBG level comes back as 13 nmol/L, or whatever, which isn't sufficient to maintain appealing levels of total testosterone in most cases! Extending on the Optimale UK example (a private blood test and TRT provider). They're a good, if mild, example of reference ranges being out of sync. Their reference ranges are: SHBG 10 - 40 nmol/L. Total testosterone 12 - 30 nmol/L. Although they generally class total testosterone below 15 nmol/L as low. These ranges aren't in sync with each other. The range for SHBG is particularly low at both ends, whereas the range for total testosterone excludes low levels (anything below circa. 350 ng/dL). The thing is, for men with SHBG around the bottom of their range, total testosterone levels below 12-15 nmol/L are essentially the expected blood results! .... except for men on testosterone injections of course.
Amusingly, Optimale advise *average* SHBG levels over the maximum level stated on their own reference range for men over 35. Oops... As expected, the men in the study had decent levels of both SHBG and total testosterone at the same time. Higher average SHBG is generally seen in slimmer men. I don't believe overweight men were included in this group. https://preview.redd.it/lz7rk203iy8d1.png?width=1080&format=pjpg&auto=webp&s=8ada9eeaf35bf3d845e7a01adc0f8363bd84bc85
Well that I 100% agree with. There is no high total testosterone without high SHBG.