free vs bioavailable t

tmckenzie

Member
I have been doing some reading. Seems to me that some are testing for free t, total t, and bioavailable t. I thought free t was the bioavailable. Am I wrong? I have several issues holding me back, e2 is low, prolactin is on higher end, igf was high, now in range but upper end, hgh is high, dht is high. Libido is low, as are other things that trt should help. Was feeling better a while back, but not so much now. So I am wondering about bioavailable t.
 
Free Testosterone = The Testosterone molecule that is not tightly bound to SHBG and loosely Albumin.

Bioavailable Testosterone = The Testosterone molecule that is not tightly bound to SHBG only.

Free and loosely bound Testosterone is what the body will use...that said, even at some point tightly bound becomes available but this is how we measure what the tissues in our body can use.

Low E2 is not healthy and can cause all kinds of sides like low libido and ED.

Prolactin on the higher end coupled with low testosterone could point to a Adenoma especially if LH is on the higher end as well. Higher levels of prolactin will tank libido big time...be aware of that.

High IGF 1 and HGH is a very good thing...you're lucky!

If DHT is high than so would Testosterone.
 
My endo is really concerned over the high igf and high gh levels. I have empty sella and he suspected an adenoma but could not find it on mri. I use defy for my trt and am waiting to talk with Dr. Saya about the other labs. I have never had bio T checked, they always check free and total. Last check was total 856 and free was 36. e was less than 20. prolactin was 10. I am diabetic but it is in check, adrenal insufficient but cortisol is being replaced, thyroid is being replaced and levels look good. I have taken myself off the small dose of arimidex I was on, but in the past I have not had any libido unless my estradiol was tanked. We never have been able to figure that out. But that was before I knew all my other hormones where out of wack, so maybe I will do better with higher e levels now. It is coming up as nipples are itching this morning some.
 

hCG Mixing Calculator

HCG Mixing Protocol Calculator

TRT Hormone Predictor Widget

TRT Hormone Predictor

Predict estradiol, DHT, and free testosterone levels based on total testosterone

⚠️ Medical Disclaimer

This tool provides predictions based on statistical models and should NOT replace professional medical advice. Always consult with your healthcare provider before making any changes to your TRT protocol.

ℹ️ Input Parameters

Normal range: 300-1000 ng/dL

Predicted Hormone Levels

Enter your total testosterone value to see predictions

Results will appear here after calculation

Understanding Your Hormones

Estradiol (E2)

A form of estrogen produced from testosterone. Important for bone health, mood, and libido. Too high can cause side effects; too low can affect well-being.

DHT

Dihydrotestosterone is a potent androgen derived from testosterone. Affects hair growth, prostate health, and masculinization effects.

Free Testosterone

The biologically active form of testosterone not bound to proteins. Directly available for cellular uptake and biological effects.

Scientific Reference

Lakshman KM, Kaplan B, Travison TG, Basaria S, Knapp PE, Singh AB, LaValley MP, Mazer NA, Bhasin S. The effects of injected testosterone dose and age on the conversion of testosterone to estradiol and dihydrotestosterone in young and older men. J Clin Endocrinol Metab. 2010 Aug;95(8):3955-64.

DOI: 10.1210/jc.2010-0102 | PMID: 20534765 | PMCID: PMC2913038

Beyond Testosterone Podcast

Online statistics

Members online
7
Guests online
236
Total visitors
243

Latest posts

Back
Top