T Nation

Free Testosterone Level

I’ve read so much about HRT for men that it’s become a jumble in my head (of course it could be my low free T causing the confusion).

Here’s my question. While on TRT you get your T levels into the upper range (900’s) and your estrogen is in the low range but your “free T” levels are still low, what do you do?


??? I doubt you’ll have low free T with TT 900. If so you have a SHBG problem. Do you have this issue?

Not that I know of. I’ll have to try to get that test.

So, nothing can be done to increase free T?

That requires lowering SHBG. SHBG tracks E levels. Serum E2=22pg/ml [0-54] would be your best bet. Testing serum E2 would be more to the point.

The cause and effect is different.

High SHBG results in any given amount of free test yielding a higher total testosterone level than one would, lacking the SHBG knowledge, expect.

While true that if we know the total T and we know SHBG is high then we know that free T is lower than otherwise would be expected for that total T, it is not the case that the SHBG is a causative factor of the free T being low.

An analogy might help illustrate. Suppose we measure “total body testosterone” by some imaginary CAT-scan-like method.

Now a say moderately fat guy, for same blood levels of testosterone, will have way more total body testosterone due to the amount dissolved in fat.

But if the moderately fat guy asks, “My total body testosterone is high but my free T is low,” the reason for his low free T is not that he is fat, and the way for his free T to improve is not that he needs to lose fat.

Because of the nature of chemical equilibria, the phenomenon does exist that free T will be “lower than expected” for given total body testosterone when fat, but that does not mean that storage of testosterone in body fat is the cause of low free T. Rather, the free T is what the free T is, and the high total value is because there is a lot of fat. (

Yes, I know that higher aromatase activity associated with fatness could yield lower free T particularly when frankly obese but that is a different mechanism not analogous to our problem here and is not intended as part of the illustration. No illustration is perfect, or few are anyway.)

Ditto for high SHBG.

The low free T is caused by low LH or poor testicular sensitivity.

Thanks for the responses to the question, I really appreciate the time you guys took to answer.

Regarding the E levels, that was tested also, I’ll just post the results. I need to mention that this test was taken the day after I injected 50 mg cyp. (and because of that I’m retesting next week with no TRT for 2 weeks prior) Anyway, here’s what came out of the test…

TT 901 (range 250-1100)
Free T 146 (range 46-224)
E 19 (range 13-54)
T3 331 (range 230-420)

Is my free T low? I was told it should be higher to get the well being benefits of HRT. I was also told these ranges are for 70 year old men. I’m 53

(of course all this might not matter since that was my levels about 24 hours after the 50mg injection.)


No, that is midrange of the stated range. Actually a little above the arithmetic midrange.

True it’s nicer to be at the high end, but your level is not what would be called low within that stated range.

I have doubt whether the ranges “are for 70 year old men.” That seems extremely unlikely. I have never heard of a lab test having normal range designed that way.

However I also can’t comment on the numbers you provide as there are no units (don’t know if these are picomolar or pg/mL, and don’t know whether this is true free testosterone or one of the poor-quality measurements.)

Another factor in the SHBG game is that testosterone has a higher affinity for SHBG than estrogen, according to my doctor. So even if higher E leads to more SHBG, SHBG is more likely to grab T than it is to grab E.

E is evil.