Why Your Testosterone Is Low (It's Not Your Testicles)

Why Your Testosterone Is Low When Your Testicles Work Fine

Most low testosterone in men under 50 is not a testicle problem. It is a signaling problem that starts in the brain, and the testicles are just doing what they are told.

Here is how the signal travels from top to bottom. Your hypothalamus releases a hormone that tells your pituitary to release two more hormones, LH and FSH, and LH is the one that travels down to the testicles and tells the Leydig cells to make testosterone. Every link in that chain has to fire for the number on your lab report to be good.

When the testicles themselves are broken, that is primary hypogonadism, and you see it on labs as low testosterone with high LH, because the brain is screaming and nobody is answering.

90% of the guys that come to my clinic and who we run labs for, they don't struggle with a problem of inability to produce testosterone. They're experiencing what's called secondary hypogonadism, which is basically a function at the pituitary. Low testosterone, and LH that is low or sitting unimpressively in the middle of the range, which means the signal never got sent in the first place.

And most of the time, that function at the pituitary or the hypothalamus is coming from some type of lifestyle-related problem.

They're eating too much processed food and not enough protein, loading up on refined carbohydrates and junk instead. They're skipping sleep and skipping training, missing the basic things that should be in place, and that gap is what causes the deficiency downstream for the production of testosterone.

Sleep is the one I see underrated the most. In a study by Leydig and colleagues, healthy young men were restricted to five hours of sleep a night for one week, and daytime testosterone dropped 10 to 15 percent, which in a week of bad sleep is the equivalent of aging ten or fifteen years.

Fat tissue plays its own role here, and for a separate reason entirely. It carries an enzyme called aromatase, which converts testosterone into estradiol, and estradiol feeds back on the hypothalamus and pituitary to turn the signal down. More fat, more conversion, quieter signal, less testosterone, which makes it easier to gain fat. That loop just keeps circling back on itself and getting worse.

Underfueling does the same thing from the other direction. When calories are chronically low or training volume is high relative to intake, the hypothalamus deprioritizes reproduction, because making sperm is expensive and your body does not think this is a good week for it.

On the clinic side, the picture looks a little different. What I would say is typically for most TRT clinics, if we're looking to prescribe testosterone as an injectable, you're really not gonna see anybody who's willing to prescribe it at a total test level of greater than 350 or 400. Some will go higher, but that's kind of best practice.

I don't think there's any specific prescribing guideline to limit it, but when you start giving testosterone to people who have higher levels, especially above 400, you're kind of opening the door to people asking questions, right? And most of these TRT clinics are, you know, TRT mills, they're trying to just get as many subscriptions out as they can.

What they're just trying to do is just make money, right? So in that case, they're also under a lot more scrutiny when it comes to making sure that they're doing it in a responsible or ethical way, for lack of a better term.

Most of what I know about this came out of conversations in the free community, so if you want the rest of it and somewhere to ask, the men's group is here: https://www.skool.com/jh-iron-forge-brotherhood/about

Research: Leydig et al., Effect of 1 Week of Sleep Restriction on Testosterone Levels in Young Healthy Men, JAMA 2011.