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Free Testosterone & SHBG

Hi All,

I’m new here, age 41, lifted weights since I was 16, got side tracked from 26-32 or so, but have been going pretty steady since then with only occassional time off to let my body heal up. Anyway, I have been noticing a decline in strength over the past year, with lots of elbow & knee stiffness, and I seem to fatigue much more quickly during workouts. Oddly, the joint pain seems to get worse when I take supplements, especially arginine and zinc for some reason. At the same time, I was noticing that my libido was gone. I never seem to have interest in initiating sex with my wife anymore. So I went to my Dr. and asked him if I could get my testosterone level checked. A few days later it came back as follows:

Total Testosterone 759 Scale (250 - 1100)
Free Testosterone 60.7 Scale (35 - 155)

Of course to him it looks great, so he won’t take it any further, but to me, that Free Test can and should be much higher. He didn’t do SHGB & I doubt he thinks it is even justified, but since my Albumin is only 4.6, I’d have to think that my SHBG is really high. I guess my questions are:

  1. Should I bother asking him to do SHBG & E2 levels?
  2. Should I try to find a endocrinologist or a Dr who is more in tune with matters like this.
  3. Since my Total T level looks pretty good for a 41 yr old (in my opinion), should I focus on diet and supplements to address this (and if so, where should I start).

I mostly want to get my libido back. Some more energy and power in the gym would be nice, but I really miss the sex drive the most.


Hi pvbbos,

There is a T replacement forum that would be more helpful to your post. Check under Forums - T replacement. Good luck

Free testosterone tests are very unreliable, and you should not make any decisions based on them. In any case, it does not take high levels of testosterone to have good libido - various studies have shown that above a certain (low) minimum of morning TT of about 400 ng/dl if I remember correctly, libido tends to be independent of testosterone level.

So be careful not to be blinded by the idea of testosterone because it may make you miss whatever the real underlying problem may be. It is possible that your free estrogen levels may be low (especially if zinc, an aromatase inhibitor that lowers estrogens (estradiol), gives you joint pain).

Did your libido drop before or after you started taking zinc?

Sufficient estrogen levels are very important for libido. It may be that you got so much zinc accumulated that estradiol is still being suppressed and that you may just have to wait it out until all the extra zinc gets metabolized by the body. One problem with this hypothesis is that there is no good test to see if your estradiol is good. The regular estradiol tests will give you total estradiol, not the biologically relevant free estradiol. Various studies have shown that even though with age, total estradiol tends to remain the same or rise, free estradiol tends to drop, and it is the free estradiol levels that correlate better with how you feel. The free can be low even if the total is high. However, even should you get the free estradiol test, each person functions best at his own idiosyncratic level, so there is no “optimal” level, making it really hard to determine if something is wrong.

Another possibility (that influences libido even more than testosterone) is thyroid, so get that tested. Also, the join pain and stiffness may indicate some underlying rheumatic or autoimmune problem, so if your thyroid is good it may be a good idea to see a rheumatologist.

Have to double up on the thyroid issue. We are finding that most guys who land on the T-replacement forum have thyroid problems and iodine deficiencies.

The major point is that many of the symptoms of [subclinical] hypothyroidism are the same symptoms of hypogonadism.

See the ‘thyroid basics’ sticky there.

And you can always get lab work on your own [in the USA].

TSH, fT3, fT4
PSA for older guys
fasting cholesterol
fasting glucose

Post labs at T-replacement
Other issues: see the ‘advice for new guys’ sticky there