Can some help me to understand the various free testosterone units and ranges?

[grantmills]

I keep seeing free testosterone presented a variety of ways and I'm not really sure what is actually being measured vs calculated and what the reference ranges actually mean. Total Test seems much easier to make sense of. The reason I ask is that my brother just called and had his test levels run. His total test was 650ng/dl and his free test was 70pg/ml (35-144 ref range). My total test before starting TRT was 340ng/dl but my free test was HIGHER than his at 72pg/ml. I don't really understand what this means can someone walk me thru it? Did we actually have similar amounts of available test even though our total test numbers were so so different? He is my half brother if that makes a difference. Is 72 an ok level? Also in another forum where I have read things, many guys say 30 is their ideal free T number. What unit is this and why is it different than my and my brother's lab work? Any help would be appreciated.

My pre TRT free test said the following and my SHBG was 25. I haven't had follow up bloodwork on TRT bc I'm only 8 weeks in.

Testosterone Fr., Calc.

72 pg/mL

47 - 244 pg/mL

 

[mairomaster]

The guys who are saying 30 is their ideal number mean ng/dL. That would be 300 pg/mL.

 

[Systemlord]

My total test before starting TRT was 340ng/dl but my free test was HIGHER than his at 72pg/ml.

You more than likely have lower SHBG and your brother probably has higher SHBG which binds testosterone. Men with low SHBG will have higher Free T at lower Total T values when compared with those who have higher SHBG.

 

[Walker DC APRN]

To calculate Free Testosterone, see the link below. You need your Albumin, SHBG, and Total Testosterone numbers.
http://www.issam.ch/freetesto.htm
These calculated parameters more accurately reflect the level of bioactive testosterone than does the sole measurement of total serum testosterone. Testosterone and dihydrotestosterone (DHT) circulate in plasma unbound (free approximately 2 - 3%), bound to specific plasma proteins (sex hormone-binding globulin SHBG) and weakly bound to nonspecific proteins such as albumin. The SHBG-bound fraction is biologically inactive because of the high binding affinity of SHBG for testosterone. Free testosterone measures the free fraction, bioavailable testosterone includes free plus weakly bound to albumin.

 

[madman]

I keep seeing free testosterone presented a variety of ways and I'm not really sure what is actually being measured vs calculated and what the reference ranges actually mean. Total Test seems much easier to make sense of. The reason I ask is that my brother just called and had his test levels run. His total test was 650ng/dl and his free test was 70pg/ml (35-144 ref range). My total test before starting TRT was 340ng/dl but my free test was HIGHER than his at 72pg/ml. I don't really understand what this means can someone walk me thru it? Did we actually have similar amounts of available test even though our total test numbers were so so different? He is my half brother if that makes a difference. Is 72 an ok level? Also in another forum where I have read things, many guys say 30 is their ideal free T number. What unit is this and why is it different than my and my brother's lab work? Any help would be appreciated.

My pre TRT free test said the following and my SHBG was 25. I haven't had follow up bloodwork on TRT bc I'm only 8 weeks in.

Testosterone Fr., Calc.

72 pg/mL

47 - 244 pg/mL

Unfortunately, when it comes to the reference ranges for measured or calculated FT they vary between different labs, and as of now, there is no standardization let alone a harmonized reference range.

Efforts are underway to standardize the procedures for FT and to generate harmonized reference ranges.

The best bet is to use the most accurate testing methods such as the gold standard Equilibrium Dialysis or Ultrafiltration (next best) if you truly want to know where your FT level sits.

Regarding calculated, there are flaws in the old linear law-of-mass action models such as the most commonly used Vermuelen.

 

[madman]

Why TruT™

Free testosterone calculator by FPT. Improved accuracy of free T calculations.

tru-t.org

About TruT™ Free Testosterone Calculator

Free testosterone calculator by FPT. Improved accuracy of free T calculations.

tru-t.org

“Circulating testosterone is bound tightly to the SHBG protein with high affinity and to albumin with substantially lower affinity; therefore, alterations in SHBG greatly affect free testosterone concentrations. SHBG levels are quite sensitive to overall health status and age. This has significant clinical implications; for example, two patients may produce equal amounts of total testosterone but one may express higher level of binding protein, lowering the free testosterone concentrations. Accordingly, if sole clinical marker for diagnosis is based on total testosterone, individuals with high binding protein levels will be misdiagnosed and not receive the necessary care.Therefore, accurate determination of free testosterone levels is central to definitive diagnosis of androgen related disorders”

 

[grantmills]

The guys who are saying 30 is their ideal number mean ng/dL. That would be 300 pg/mL.

Is 72 pg/mL a low number?

You more than likely have lower SHBG and your brother probably has higher SHBG which binds testosterone. Men with low SHBG will have higher Free T at lower Total T values when compared with those who have higher SHBG.

My brother was asking if he would be a candidate for therapy or at least explore the idea of it. I don't really know what he is experiencing outside of his comments of lacking energy and getting nagging small injuries (he's a former professional baseball player). 650 ng/dl seems awfully sufficient for a man in his early 40s even though his free test is lower than mine naturally. DO men with high total t and lower end free T receive TRT treatment typically or are there other ways to lower SHBG without injections?

 

[sammmy]

You can determine if a FREE testosterone measurement is low or high only if you know the reference range of the corresponding lab - see where it sits in the reference interval. As said above, different labs have different reference ranges for FREE testosterone so a value from one lab is not comparable to values from another lab or to online calculators that also have different ranges.

Values of TOTAL testosterone are usually more comparable because the normal lab ranges are typically similar.

Trying to lower your SHBG is a lost cause because most things that lower SHBG will also lower Total and Free testosterone. You should focus on how you feel, which is the real factor you want to change, not some lab values. Even the free testosterone lab value is sometimes increased (see examples below) but you do not feel any positive change.

Things that successfully increased FREE testosterone for me: Arimidex (large effect, very obvious boost in sexuality, side effects: made me feel depressed with low energy and hurting joints), Boron/Borax (minor increase ~ 15%), Nettle Root Extract (supposedly binds to SHBG and displaces testosterone, minor increase ~ 10%, no sexual effect felt - it blocks DHT which is counterproductive), Tongkat Ali extract (no sexual effect felt but increased free testosterone ~20%, however it may block DHT so again counterproductive), Proviron (minor increase ~10%), HCG 1000 IU injected every other day (about doubled my free testosterone, effect felt sexually - much easier orgasm, no effect felt at the gym), DHEA (gives stamina at the gym, increases libido and orgasmic ability for me, not measured if it changes free testosterone).

Your brother could try Boron, Zinc, and/or DHEA and see if these improve how he feels. Boron and DHEA act a bit like stimulants for me.

 

[sammmy]

Also, since your brother is in my age range, and have similar complaints (low energy and frequent injuries) I strongly suggest what works for me:

1. Breakfast rich in fast sugars - everything we crave but know is bad. I usually have bread with blueberry jam, but he can try chocolate, ice cream etc. Such a breakfast actually seems to boost my metabolism and I don't feel lack of energy later in the day.

2. Cyanotis Vaga extract (Beta Ecdysterone) 1-2 grams/day. This acts on estrogen receptors and boosts endurance, improves recovery, and heals old injuries at the gym. It also swells the muscles a little. It will not shut down his body production of testosterone, unlike anabolic steroids.

 

[Walker DC APRN]

Some factors which lower SHBG are high levels of insulin (Diabetes Type 2), Growth Hormone, IGF-1, Prolactin, Transcortin, and Testosterone.

Whether someone is a candidate for TRT depends on several things. Lab numbers matter. What matters just as equally if not more is their symptoms and how they feel. Lacking energy and nagging small injuries can be a symptom of a less than optimal Free T for that person. Many factors need to be considered. Once on TRT I look to see how the person responds. Mostly on how they feel.

In general, there is an opinion a Free T of around 20 is optimal. But, I have had patients on TRT with a Free T of 14 and they felt absolutely great. I have seen other patients on TRT who had a Free T in the 20s (with everything else optimized), and they did not feel dialed in. Some guys just need more T because that is how their engine runs. Everyone is an individual.

 

[grantmills]

Some factors which lower SHBG are high levels of insulin (Diabetes Type 2), Growth Hormone, IGF-1, Prolactin, Transcortin, and Testosterone.

Whether someone is a candidate for TRT depends on several things. Lab numbers matter. What matters just as equally if not more is their symptoms and how they feel. Lacking energy and nagging small injuries can be a symptom of a less than optimal Free T for that person. Many factors need to be considered. Once on TRT I look to see how the person responds. Mostly on how they feel.

In general, there is an opinion a Free T of around 20 is optimal. But, I have had patients on TRT with a Free T of 14 and they felt absolutely great. I have seen other patients on TRT who had a Free T in the 20s (with everything else optimized), and they did not feel dialed in. Some guys just need more T because that is how their engine runs. Everyone is an individual.

So using my numbers and my brother's numbers, our Free T is 7 and 7.2 respectively on the scale you are using here. Seems like a piss poor number to have. Interesting stuff. My natural SHBG of 25 seems to be on the lower end of normal. My prolactin is on the lower end of normal as well. I have never tested GH, IGF-1 or Transcortin. Will be interesting to see my bloodwork in a month or so. After nearly 8 weeks I have gained 10 pounds and have tons of energy. Way more than I felt before I mean I can lift weights in the morning, go for a 15 mile bike ride in the afternoon, sleep 7 hours then do it all over again. Also my digestion is great. This may be TMI but I have been having many stools where I don't even need to wipe. It's really a huge change. The only thing funky is my sex drive. Some days I need to have sex 5 times and then I can take it or leave it for a few days then boom 5 times. If I can figure that part out perfectly I will be completely sold on TRT.

 

[Walker DC APRN]

So using my numbers and my brother's numbers, our Free T is 7 and 7.2 respectively on the scale you are using here. Seems like a piss poor number to have. Interesting stuff. My natural SHBG of 25 seems to be on the lower end of normal. My prolactin is on the lower end of normal as well. I have never tested GH, IGF-1 or Transcortin. Will be interesting to see my bloodwork in a month or so. After nearly 8 weeks I have gained 10 pounds and have tons of energy. Way more than I felt before I mean I can lift weights in the morning, go for a 15 mile bike ride in the afternoon, sleep 7 hours then do it all over again. Also my digestion is great. This may be TMI but I have been having many stools where I don't even need to wipe. It's really a huge change. The only thing funky is my sex drive. Some days I need to have sex 5 times and then I can take it or leave it for a few days then boom 5 times. If I can figure that part out perfectly I will be completely sold on TRT.

 

[Walker DC APRN]

In TRT the goal is to stay at a steady level of Free T to feel optimal. With a lower SHBG the Free T leaves more quickly. In general, lower doses of T with more frequent injections helps one to stay more steady. SHBG can move around depending on certain factors.

Everyone I see knows how to eat right, train right, and to get enough sleep. I am just helping them with the missing piece of the puzzle. T helps increase libido, which means having the energy to get off of the couch to do the things you want to do but had no energy and motivation to do so, during your slow death spiral into a zombie state over the past several years, down into a low T situation.

Sex drive can move around depending on how busy you are doing other things which take up your energy.

T is part androgenic and anabolic. Increases in stamina and strength in the gym are inevitable.

 

[TucsonJJ]

I keep seeing free testosterone presented a variety of ways and I'm not really sure what is actually being measured vs calculated and what the reference ranges actually mean. Total Test seems much easier to make sense of. The reason I ask is that my brother just called and had his test levels run. His total test was 650ng/dl and his free test was 70pg/ml (35-144 ref range). My total test before starting TRT was 340ng/dl but my free test was HIGHER than his at 72pg/ml. I don't really understand what this means can someone walk me thru it? Did we actually have similar amounts of available test even though our total test numbers were so so different? He is my half brother if that makes a difference. Is 72 an ok level? Also in another forum where I have read things, many guys say 30 is their ideal free T number. What unit is this and why is it different than my and my brother's lab work? Any help would be appreciated.

My pre TRT free test said the following and my SHBG was 25. I haven't had follow up bloodwork on TRT bc I'm only 8 weeks in.

Testosterone Fr., Calc.

72 pg/mL

47 - 244 pg/mL

Lots of factors to consider... I am no expert, but have done a lot of reading... I wiuod say that a level of 70pg/ml, which equates to 7.0 ng/dl may well be low... IF symptoms of Low T are present. The range of 35-144pg/ml, (3.5-14.4/ng) probably Sonora Quest, IMO, is an outrage... anyone with a Free T of 35pg (3.5ng) is actually on potentially dangerous ground in terms of much higher prostate cancer risk and heart trouble. Yes, many think that 20-30ng is a "sweet spot"... sounds about right, but again, consultation with a physician/pro who knows what they are doing (very rare) is important. Free T test ranges vary widely, which shows they are goofy.
MY Free T has been low for years, but my Docs were all to dang dumb to mention it... last two tests, 5.2 Free T... (range 6.6-18.1 per LabCorp) and yes, I have had serious symptoms for YEARS. Estradiol is a bit high at 39 too. I am finally going to see a knowledgeable Doc and get on TRT. I have seen no less than 7 physicians who knew nothing about hormone imbalance... frustrating and dangerous!

 

[Systemlord]

Is 72 pg/mL a low number?



My brother was asking if he would be a candidate for therapy or at least explore the idea of it. I don't really know what he is experiencing outside of his comments of lacking energy and getting nagging small injuries (he's a former professional baseball player). 650 ng/dl seems awfully sufficient for a man in his early 40s even though his free test is lower than mine naturally. DO men with high total t and lower end free T receive TRT treatment typically or are there other ways to lower SHBG without injections?

SHBG is one of those things that are almost impossible to control, it increases as we age and there are genetic factors to consider. For those men who don't have low-T do to a pituitary or testicular problem and just have high SHBG and low Free T, TRT is the only treatment.

Sometimes SHBG is elevated because someone has low-T, it's the way the body attempts to scavenge what little T remains in the body. Getting a sick care doctor to prescribe TRT with high Total T and low Free T is another story altogether. A lot of doctors, providers are scared to death to prescribe TRT (steroids) and will just ignore low levels are deny treatment.