Happy Tuesday!
I just dropped a brand new masterclass on Tesamorelin, and this one might be my favorite of the year so far.
Watch it on YouTube here: https://youtu.be/V_Yd07NqXYM
Or listen on Spotify here: https://open.spotify.com/episode/2iLBbh7Q6U9P6DKw3ZX3KW?si=SLRyB6zSQv2YZCFLpNHAHw
Here's a summary of what I covered.
Tesamorelin
It's a synthetic analog of growth hormone-releasing hormone, or GHRH. That means it tells your pituitary to release GH in natural pulses. Think of it like a thermostat. Your hypothalamus is the dial, your pituitary is the furnace, GH is the heat, and IGF-1 is the room temperature you actually feel.
So you inject Tesamorelin, your pituitary fires, your liver makes IGF-1, and the feedback loops stay intact. That's the big difference from injecting straight HGH (although I still love HGH). When you come off, you're right back where you started. No shutdown, no downtime.
It's also the only FDA-approved peptide for reducing visceral fat.
The Numbers
This is where Tesamorelin earns its reputation.
In clinical studies, we see a 15-18% reduction in visceral fat over 26 weeks.
We also see a roughly 37% reduction in liver fat over 12 months in patients with fatty liver.
IGF-1 typically climbs 80 to 110% at the 2mg dose, which can restore levels you'd see in a healthy young adult. Triglycerides usually fall too, which is huge for long-term heart health.
There's a 2012 trial showing improved executive function in older adults. So this isn't only a body composition tool. The brain benefits are real, even if the evidence base is thinner.
For the right person, the data is hard to argue with.
Dosing and Water Retention
1mg per day is the general sweet spot for most people, especially women.
2mg per day is the FDA-approved clinical dose and the workhorse for serious visceral fat loss.
If you're already lean, that 2mg dose can blow you up like a water balloon. I sit around 10% body fat most of the year, and at 2mg, I get puffy, bloated, and my face fills out. So I personally stick to 1mg.
However, someone carrying 50 or 75 pounds of fat barely notices the water and transforms their body over 16 to 24 weeks. Match the dose to the goal. Take it at bedtime, ideally an hour or two after your last meal, so insulin is low.
Cycling
Because it's FDA-approved, we actually have antibody data on this one.
Anti-Tesamorelin antibodies develop in about half of patients after 26 weeks.
They're non-neutralizing, but the practical effect is that your body slowly stops responding. Cycling breaks that pattern and lets you come back fresh.
I also like cycling because we have no safety data past 18 months. With peptides, I'd rather respect what we don't know.
A simple pattern is 12 weeks on, 4 weeks off. People with a lot of visceral fat or fatty liver can run longer, then take a real break. Just don't sit on it forever without a pause.
Stacking
Tesamorelin shines as part of a system, not on its own.
My go-to is testosterone, a GLP-1-like tirzepatide/retatrutide, and Tesamorelin together.
Testosterone drives muscle, GLP-1 drives overall weight loss, and Tesamorelin specifically targets visceral fat. 1+1=3.
I love it alongside a GLP-1 for muscle preservation too. If you're on a GLP-1 and losing muscle, there's almost no reason not to add Tesamorelin.
A couple of cautions. Don't stack it with sermorelin or CJC. They fight over the same receptor. And go easy stacking with ipamorelin. It's the strongest GH stack out there, but the water retention is no joke.
Final Thoughts
If I ranked every peptide, Tesamorelin lands solidly in my top 10. Not top 5, but close.
For someone whose DEXA scan shows a dangerous level of visceral fat, this is the best tool we have outside of a GLP-1.
But it's not a magic wand. The benefit is treatment-dependent, so the lifestyle work matters most when you cycle off. Get your hormones, sleep, and training dialed in first, then bring Tesamorelin in to do what it does best.
When done right, by the right person, it moves the needle more than almost anything else in the GH category.
Thank you for being a supporter of my work!
Best,
Hunter Williams