Pay attention to the Q&A (43:20-56:30) especially when it comes to testing free testosterone!
43:20-46:27 - How do we assess for free testosterone?
* There's a direct antibody assay (IA) that measures free testosterone it is notoriously inaccurate and notoriously underestimates the true free testosterone as much as 30% so you should never use that but it is cheap, its easy, its quick so all labs offer it
In this debate, two clinicians discuss the merits and demerits of the free testosterone hypothesis. Although most clinical guidelines recommend the measurement of free testosterone in the evaluation for male hypogonadism (at least in men with suspected low serum sex hormone binding globulin), there remains controversy about underlying hypothesis that serum...
This is a picture of Hershey kisses drawn by me and this is the kisspeptin neurons that regulate the hypothalamus to make GnRH to and create the onset of puberty
Aging and androgens: Physiology and clinical implications (2022) Bradley D. Anawalt · Alvin M. Matsumoto
Abstract
In men> ~35 years, aging is associated with perturbations in the hypothalamus-pituitary–testicular axis and declining serum testosterone concentrations. The major changes are decreased gonadotropin-releasing hormone (GnRH) outflow and decreased Leydig cell responsivity to stimulation by luteinizing hormone (LH). These physiologic changes increase the prevalence of biochemical secondary hypogonadism—a low serum testosterone concentration without an...
Relationships between endogenous and exogenous testosterone and cardiovascular disease in men (2022) Arthi Thirumalai · Bradley D. Anawalt
Abstract
In this narrative review, we discuss the evidence about the controversy about the cardiovascular effects of endogenous and exogenous testosterone in men. Prospective cohort studies with follow-ups of~5–15 years generally indicate no association or a possible inverse relationship between serum endogenous testosterone concentrations and composite major cardiovascular events, cardiovascular deaths, and overall...
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.
