How would you know if you have low testosterone?
First off, you’d most likely suffer from some of the common symptoms, including…
- Low libido
- Erectile difficulties
- Fatigue and brain fog
- Weight gain
- Depressed mood
If you check off several of these symptoms, it’s certainly worth getting your levels checked.
However, checking your testosterone is more nuanced than you think.
Most people believe you just need to get a total and free testosterone level and you’re good to go.
That couldn’t be further from the truth.
What you need is a much more complete picture so you know with certainty what is truly going on within your body hormonally and so you can track progress over time.
Given this, I want to break down the base labs I check with my clients and why we use them.
Total testosterone — this is the total amount of circulating testosterone in your blood.
Free testosterone — this is the amount of testosterone that is free to enter the cell and is the most important marker when it comes symptoms. Much more so than total testosterone.
The most accurate measurement of free testosterone is via equilibrium dialysis. This is rarely done and expensive, so the best way of measuring your free T is to calculate it using total testosterone, albumin, and SHBG and then plugging those markers into a calculator like this one: http://www.issam.ch/freetesto.htm
*** Free testosterone is different than bioavailable testosterone, which is a measure of the free testosterone + testosterone bound to albumin.
Albumin (which you get with a CMP or complete metabolic panel) — This is a protein found in the blood which some of your testosterone will be bound to.
Albumin can be used to help calculate free testosterone levels, as mentioned above.
SHBG — Sex hormone binding globulin, as the name implies, binds sex steroids, including testosterone and estrogen. When sex steroids are bound to SHBG, they are rendered inactive.
We use this along with albumin and total testosterone to calculate free testosterone levels.
FSH + LH — these are hormones produced by your pituitary gland and stimulate the production of testosterone.
If these are abnormal it can help you understand where the problem is.
- If FSH and LH are high but testosterone is low, the problem is within the testes.
- If FSH and LH are low and testosterone is low, then the problem is central, or coming from the brain. The 2 most common causes of this are sleep deprivation and high stress.
Estradiol — this is the main form of estrogen in the body. Elevated estradiol levels can mimic low testosterone symptoms, including low libido, fatigue, brain fog, and weight gain.
This is also important to monitor is you are on testosterone replacement therapy (TRT) because your testosterone can convert to estradiol via a process called aromatization.
DHEA-S — This one of the main precursors to your sex steroids. A low DHEA-S level can indicate increased levels of stress or inflammation within the body and affect testosterone levels.
CBC — A complete blood count measures things like your white blood cells, red blood cells, and clotting. This is more important if you are on TRT because it can increase your hemoglobin and hematocrit — essentially the density of your red blood cells.
An increased hemoglobin and hematocrit increases the viscosity or thickness of your blood, which increases your risk for clotting (strokes, heart attacks, deep vein thrombosis, and pulmonary embolisms).
PSA — Prostate-specific antigen is a good practice for men to screen and monitor for prostate cancer.
The labs mentioned above help you understand your hormone levels but don’t tell you much about the upstream factors that may be causing issues… and there are many.
Here are some of the upstream nutritional factors I will also check and make sure to optimize:
- Plasma Zinc
- 25-OH Vitamin D
- RBC Magnesium
- Vitamin B6 (measured via Xanthurenic and Kynurenic acid)
- Whole Blood Glutathione
- Folate and B12 (measured via FIGLU and MMA)
- Serum CoQ10
The main thing to understand is that if your testosterone is low there is almost always a reason for it and it rarely has solely to do with age.
It is typically a results of upstream imbalances leading to the development of low testosterone downstream.
And proper testing is an important step in helping to identify what those imbalances may be so that you can be targeted in correcting them.