T Nation

Low Total T, Normal Bioavailable T



I am a 24 year old male. I have many of the symptoms of low T(fatigue decreasing/MIA libido, brain fog, late puberty, less body hair, mood swings, trouble gaining strength and muscle) and many of these have worsened in the past year or so.

I had bloodwork done in July through Labcorp and had the following:

Testosterone, Serum 407 348-1197 ng/dL BN
Testosterone,Free 10.99 5.00-21.00 ng/dL BN
% Free Testosterone 2.70 1.50-4.20 % BN
Estradiol, Sensitive 8 3-70 pg/mL BN
TSH: 4.22 mIU/L 0.50-6.00 mIU/L

In late August I saw a GP and at my urging he redid some of the tests, resulting in:

Testosterone, total 206 ng/dL 250-950 ng/dL
Cortisol: 10.1 ug/dL 7.0 - 22.0 ug/dL
ACTH: 21 pg/mL 5-52 pg/mL
Leutinizing Hormone: 1.4 mIU/mL 1.7-11.2 mIU/mL
FSH: 3.1 mIU/mL 1.0-42.5 mIU/mL
TSH: 2.55 mIU/L 0.50-6.00 mIU/L

He referred me to an Endo who wanted yet more tests, which were done on 9/5:

Testosterone, total: 391 ng/dL 240-950 ng/dL
Testosterone, bioavailable: 168 ng/dL 83-257 ng/dL
Leutinizing Hormone: 2.2 mIU/mL 2-12 mIU/mL
FSH: 3.1 mIU/mL 1.5-10.0 mIU/mL

So it seems like my total T is borderline low and certainly low for my age, but my bioavailable T is right in the middle of the range. My endo was considering secondary hypogonadism prior to the latest test, but she says the bioavailable T number is all that matters to her and considers my case closed. I'm wondering if anyone can shed light on why the numbers disagree and what could be causing my symptoms if not hypogonadism?


Doctors often get caught up in the lab ranges, and the lab ranges are really only to identify illness. You can have a diminished quality of life without having a life threatening illness.

Bioavailable testosterone is the sum of free testosterone and testosterone weakly bound to albumin. Free testosterone is measured using the relationship of total testosterone and sex hormone binding globulin (SHBG). Type “shippen SHBG chart” and go to google images and try it for yourself. So, you see, your subclinical testosterone deficiency would only really indicate that you have an elevated SHBG.

You do have low testosterone for your age, and you would appear to have a degree of secondary hypogonadism.

Read through all the stickies if you have not done so already. Post ALL your labs. We may catch something your doctors missed. SHBG can be tricky to modulate alone. It’s a reflection of other hormones’ statuses. Get more blood work. Specifically request the thyroid labs in the blood testing sticky. Adrenals look to be on the lower end. 4-point saliva cortisol test will be definitive. Liver function test. Insulin resistance test if you can swing it.

Quality of life and alleviation of symptoms is the goal here. We will help you with this however we can.


I got off the phone with the doctor. She’s still adamant that testosterone is fine “Total was in the range and Bioavailable looks great.” After prodding all I could get her to agree to was a retest of Cortisol because it was “on the lower side.” That test was done about 9:30AM and so she wants a retest at 8:00AM, she didn’t think the 4-point saliva was worth it.

The problem I’m having is that I’m using the student health services at my university so I cannot ask/demand anything. The only tests that will get done are the ones that the doctor decides are needed because I don’t pay for it. I do have insurance and if this ends up dead-ending I suppose I’ll go to another non-university doctor.

Does elevated SHBG imply some sort of condition? Using my July lab values and that Shippen Chart I look to be about 20 nmol/L which seems maybe a bit on the low end, but decently within the range. I guess my question is, is it important to raise my total test numbers if my bioavailable/free numbers are in the middle of the range? Would raising total test have any effect on bioavailable/free test? Which number, if any, is the controlling number for the symptoms of low T?

As you asked here are the rest of my labs:


CBC With Differential/Platelet
WBC 5.6 (4.0-10.5 x10E3/uL)
RBC 4.54 (4.14-5.80 x10E6/uL )
Hemoglobin 13.9 (12.6-17.7 g/dL )
Hematocrit 40.9 (37.5-51.0 % )
MCV 90 (79-97 fL )
MCH 30.6 (26.6-33.0 pg )
MCHC 34.0 (31.5-35.7 g/dL )
RDW 13.4 (12.3-15.4 % )
Platelets 191 (140-415 x10E3/uL )
Neutrophils 40 (40-74 % )
Lymphs 44 (14-46 % )
Monocytes 7 (4-13 % )
Eos 8 (0-7 % )
Basos 1 (0-3 %)
Neutrophils (Absolute) 2.2 (1.8-7.8 x10E3/uL)
Lymphs (Absolute) 2.5 (0.7-4.5 x10E3/uL)
Monocytes(Absolute) 0.4 (0.1-1.0 x10E3/uL)
Eos (Absolute) 0.5 (0.0-0.4 x10E3/uL)
Baso (Absolute) 0.0 (0.0-0.2 x10E3/uL)
Immature Granulocytes (0 0-2 % )
Immature Grans (Abs) (0.0 0.0-0.1 x10E3/uL)

Comp. Metabolic Panel
Glucose, Serum 99 (65-99 mg/dL )
BUN 16 (6-20 mg/dL )
Creatinine, Serum 0.96 (0.76-1.27 mg/dL )
eGFR If NonAfricn Am 110 (>59 mL/min/1.73 )
eGFR If Africn Am 127 (>59 mL/min/1.73 )
BUN/Creatinine Ratio 17 (8-19 )
Sodium, Serum 141 (134-144 mmol/L )
Potassium, Serum 4.1 (3.5-5.2 mmol/L )
Chloride, Serum 104 (97-108 mmol/L )
Carbon Dioxide, Total 22 (19-28 mmol/L )
Calcium, Serum 9.1 (8.7-10.2 mg/dL )
Protein, Total, Serum 7.3 (6.0-8.5 g/dL )
Albumin, Serum 4.9 (3.5-5.5 g/dL )
Globulin, Total 2.4 (1.5-4.5 g/dL )
A/G Ratio 2.0 (1.1-2.5 )
Bilirubin, Total 0.5 (0.0-1.2 mg/dL )
Alkaline Phosphatase, S 57 (44-102 IU/L )
Please note reference interval change
AST (SGOT) 18 (0-40 IU/L)
ALT (SGPT) 12 (0-44 IU/L )

Lipid Panel
Cholesterol, Total 149 (100-189 mg/dL )
Triglycerides 75 (0-114 mg/dL )
HDL Cholesterol 60 (>39 mg/dL )
VLDL Cholesterol Cal 15 (5-40 mg/dL )
LDL Cholesterol Calc 74 (0-119 mg/dL )

Thyroid Panel With TSH
TSH 4.220 (0.450-4.500 uIU/mL)
Thyroxine (T4) 8.6 (4.5-12.0 ug/dL)
T3 Uptake 36 (24-39 %)
Free Thyroxine Index 3.1 (1.2-4.9)

Insulin-Like Growth Factor I 247 (83-344 ng/mL)

August tests:

T3 Free: 2.6 pg/mL (2.0-4.9)
T4 Free: 1.4 ng/dL (0.75-1.54)

I will see about getting the rest of the tests you mentioned from the sticky. Thanks for the help.


[quote]Kaynon311 wrote:
your subclinical testosterone deficiency would only really indicate that you have an elevated SHBG.

I misspoke here. I meant to say your SHBG is already low.

I’m impressed you managed to get all the tests you did. They were more thorough than many private GPs are willing to be initially.

Your cholesterol is low. All steroid hormones come from cholesterol. A good start would be to eat more foods rich in cholesterol. Eggs are an easy one.

She’s right about the cortisol test. It’s generally done around 8am while fasting.