The Honest Dose #7

I got an email last week from a reader asking a fair question: "It seems you keep scoring these compounds in the 20s and 30s. Is anything in your catalog actually backed by real evidence, or is it all hype?"

It's a good challenge, and I want to answer it honestly. The truth is that most of the peptides people are excited about right now sit somewhere between weak and moderate evidence. That's just the reality of the space. A lot of the compounds generating the most buzz, the ones you see in Reddit stacks and influencer protocols, have human data that ranges from thin to nonexistent.

But not all of it. There's a smaller group of peptides that have been through the actual machinery of clinical development, real Phase 3 trials, FDA approval, the whole process. And what's interesting is that these are often not the compounds people are most excited about. The hype and the evidence frequently point in different directions.

Tesamorelin is a good example. It's a growth hormone-releasing peptide that's been FDA approved since 2010, had a meta-analysis published just this past January, and almost nobody in the wellness conversation talks about it. Meanwhile its less-evidenced cousins in the same category get all the attention. So to that reader: yes, there's real evidence in here. It's just not always attached to the names you'd expect. Let me show you what I mean.

Let's get into it.

Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH). Structurally it's a modified 44-amino acid version of human GHRH, altered to resist enzymatic breakdown and extend its half-life. It was developed by Theratechnologies and marketed under the brand name Egrifta.

Here's what sets it apart from most of the catalog: it has an actual FDA approval. In 2010, the FDA approved tesamorelin for the reduction of excess visceral abdominal fat in HIV patients with lipodystrophy, a condition where antiretroviral therapy causes abnormal fat redistribution. That approval was built on two large Phase 3 trials. This is not a research chemical that migrated into wellness. It's an approved drug with a defined clinical indication.

Tesamorelin works the same way Sermorelin does, which we covered in Issue #5: it stimulates the pituitary gland to produce and release more of your own growth hormone, rather than introducing synthetic HGH directly. It restores a more natural, pulsatile pattern of GH secretion.

What makes it clinically interesting is the specificity of where that GH goes to work. Elevated GH preferentially mobilizes visceral adipose tissue, the deep abdominal fat that wraps around organs and is most strongly linked to metabolic and cardiovascular risk. Tesamorelin reduces that specific fat depot without the broad metabolic disruption that direct HGH administration can cause. In the trials, it lowered visceral fat without significantly worsening fasting glucose or insulin resistance, which is a meaningful distinction.

Tesamorelin has one of the stronger evidence bases in the catalog, and the structure of that evidence is worth examining.

The two pivotal Phase 3 trials enrolled 816 participants combined and were published in The Lancet and the New England Journal of Medicine. They demonstrated consistent visceral fat reduction of roughly 15 to 18 percent over 26 weeks. A meta-analysis published in January 2026 pooled five RCTs and confirmed significant reductions in visceral adipose tissue, trunk fat, waist circumference, and hepatic fat, with a modest increase in lean body mass and a well-characterized safety profile assessed using GRADE methodology.

That last detail matters. GRADE is the formal framework for rating certainty of evidence, and the fact that tesamorelin has been subjected to that kind of rigorous synthesis puts it in a different tier from most peptides, where the "evidence base" is often a handful of animal studies and a pilot trial.

The honest limitations: the strongest evidence is specifically in HIV-associated lipodystrophy, the population it was approved for. The trials demonstrating its visceral fat effects in that population are robust. Its use in the broader wellness context, for general body composition or anti-aging in healthy adults, runs ahead of where the controlled evidence sits. The effect on visceral fat is real and well-documented. Whether that translates to the outcomes a healthy person seeking optimization actually wants is less established. And the effects reverse after discontinuation, which means it functions more like an ongoing therapy than a one-time intervention.

This is the part I find genuinely instructive. The growth hormone category contains several compounds that work through similar mechanisms but have wildly different evidence bases. Ibutamoren/MK-677 (Issue #2) is an oral GH secretagogue with limited human outcome data. Sermorelin (Issue #5) has moderate evidence and a previous FDA approval that was discontinued for commercial reasons. Tesamorelin sits at the top of this group: current FDA approval, multiple Phase 3 trials, a recent meta-analysis, and an 88/100 RQS.

Yet in the wellness conversation, tesamorelin is probably the least discussed of the three. That inversion, where the best-evidenced option gets the least attention, is one of the most consistent patterns I've found building this catalog.

If you want a growth hormone-releasing peptide with genuine clinical trial backing and an FDA approval, tesamorelin is the strongest option in the catalog. The evidence is concentrated in HIV-associated lipodystrophy, so extending conclusions to general wellness use requires caution. But the core finding, that it reduces visceral fat through a relatively physiological mechanism, is about as well-established as anything in this category gets.

RQS: 88/100 - Strong Evidence

Read the full Tesamorelin profile

The claim: Intermittent fasting and time-restricted eating aren't just another way to cut calories. The fasting window itself does something special, switching your body into fat-burning mode, triggering autophagy, flipping a metabolic switch that torches fat in a way ordinary dieting can't. The implication is that when you eat matters as much as how much, and that fasting unlocks results you can't get from simple calorie reduction.

The reality: Fasting works, and the metabolic benefits are real. But the best controlled evidence suggests it works mostly because it's an effective way to eat fewer calories, not because the fasting window has independent fat-burning powers.

This is the question researchers have actually tried to isolate: if you match calories between a fasting group and a regular-meals group, does the fasting group still come out ahead? When studies control for total intake, the dramatic advantage of fasting tends to shrink or disappear. A well-known trial of time-restricted eating found that limiting the eating window produced weight loss results that weren't significantly different from eating the same calories spread across the day. The timing itself wasn't the active ingredient. The calorie deficit was.

That doesn't mean fasting is useless, far from it. There's a genuinely valuable practical insight here: for a lot of people, compressing their eating window is one of the easiest ways to naturally eat less without counting anything. If you stop eating at 7pm and don't start again until 11am, you've quietly eliminated late-night snacking and a full breakfast's worth of calories, and you didn't have to track a single macro. That's a real benefit. It's just a behavioral one, not a metabolic loophole.

The metabolic markers do improve with fasting, better insulin sensitivity, improved lipids, reduced fasting glucose. But much of that improvement tracks with the weight loss and the calorie reduction, and some of it appears to come from the consistency of the eating pattern. The mechanisms people get most excited about, autophagy and metabolic switching, are real biological processes, but they're mostly characterized in cell and animal studies, and the leap to "this is why you're losing belly fat" outpaces what the human data actually shows.

The honest version of the claim: Fasting is a legitimately useful tool, but its power is mostly that it makes eating less feel easier and more structured, not that the fasting window itself melts fat through some metabolic shortcut. If time-restricted eating helps you maintain a calorie deficit without feeling deprived, that's a genuinely good reason to do it. Just know what's doing the work. The clock is helping you eat less. It isn't overriding the math.

A practical corollary: if fasting makes you so hungry that you overeat during your window, you lose the entire benefit, because the benefit was never the timing in the first place. It was the deficit.

Tesamorelin and Ibutamoren are the cleanest natural experiment in the catalog for showing what the RQS actually measures. Both are growth hormone secretagogues. Both raise GH and IGF-1 through the pituitary. On mechanism, they're cousins. Yet they're separated by a large margin in the score, and almost all of that gap lives in two specific dimensions: Study Design and Replication.

Start with Study Design, worth up to 25 points. This dimension asks what kind of studies the evidence actually rests on. Tesamorelin's foundation is two large randomized, double-blind, placebo-controlled Phase 3 trials, the highest tier of study design, with CT-measured visceral fat as a pre-specified endpoint. Ibutamoren's human evidence is thinner and lower-tier: smaller studies, shorter durations, more surrogate and pharmacokinetic endpoints than hard clinical outcomes. One compound has been tested the way drugs are tested for approval. The other mostly hasn't. That alone opens a wide point gap before you get to anything else.

Then Replication, worth up to 20 points. This is the dimension people underrate, and it's where the two diverge most sharply. Tesamorelin's visceral fat effect has been demonstrated repeatedly, across the original Phase 3 trials, multiple post-hoc analyses, and a 2026 meta-analysis pooling five RCTs from independent research groups. The finding has survived independent scrutiny. Ibutamoren lacks that web of independent confirmation. Its effects are reported in a much narrower slice of literature, without the repeated, multi-group verification that pushes a score up.

Here's the point worth sitting with: these two compounds make broadly similar promises through a nearly identical mechanism. If you were judging on how they're supposed to work, you'd score them about the same. The RQS scores them far apart because it isn't grading the mechanism, it's grading how rigorously and how repeatedly anyone has actually proven the compound does what's claimed in humans. Same mechanism, very different evidence. That difference is the entire reason the framework exists.

A correction worth making: the FDA peptide docket details. In earlier issues I cited the PCAC public comment docket as FDA-2026-N-2979. The correct docket number is FDA-2025-N-6895, and it remains open for public comment until July 22, 2026, with comments received by July 9 presented directly to the committee. I also want to clarify the agenda: the seven peptides formally up for 503A Bulks List consideration at the July 23-24 meeting are tied to specific indications and include BPC-157, TB-500, KPV, and MOTS-C, among others. Semax, Epitalon, and DSIP are part of the broader group of twelve peptides recently removed from the Category 2 "significant safety risk" list, but the formal July review list is its own thing. Getting this right matters, and correcting it openly is more in keeping with what this newsletter is for than quietly fixing it.

FDA moves to permanently close 503B GLP-1 compounding. In a separate action, the FDA proposed formally excluding semaglutide, tirzepatide, and liraglutide from the 503B outsourcing facility bulks list, which would bar large-scale compounding of these GLP-1 drugs under any circumstances, even in a future shortage. The agency cited more than 455 adverse event reports for compounded semaglutide and over 320 for tirzepatide, many involving dosing errors. A public comment period runs through June 29, 2026. This is the other side of the regulatory coin: as some peptide pathways potentially open, the compounded GLP-1 door is closing.

We've spent this issue deep in the growth hormone category, so let's end somewhere completely different, and somewhere I'm planning to take you in full next time.

DSIP, delta sleep-inducing peptide, is a nine-amino acid neuropeptide first identified in the 1970s from the blood of rabbits in a state of induced sleep. The name is almost comically literal: it was discovered while looking for a substance that promotes the deep, slow-wave (delta) phase of sleep, and that's exactly what it was named for. It sits in a category we haven't featured yet, sleep and recovery, which behaves very differently from the metabolic and growth hormone compounds that have dominated recent issues.

What makes DSIP fascinating is how poorly understood it remains despite fifty years of study. It appears to act less like a sedative and more like a modulator, something that helps regulate sleep architecture, stress hormones, and circadian signaling rather than simply knocking you out. There's research touching on its effects on slow-wave sleep, on cortisol and stress response, even on pain perception. But the human evidence is genuinely limited and often dated, and the mechanism is still not cleanly mapped. It's one of those compounds where the gap between how long it's been known and how little is settled is striking.

It's also timely. DSIP is one of the peptides connected to the current FDA compounding conversation, which makes it worth understanding now rather than later.

I'm going to make DSIP the lead in the next issue, with the full RQS breakdown, the mechanism in depth, and an honest accounting of what the sleep evidence does and doesn't support. Consider this the trailer. If you've ever wondered whether there's a peptide that actually improves sleep quality versus one that just sounds like it should, that's the question we'll dig into.

Read the full DSIP profile

Hopefully that was helpful/interesting, see you next week.

-Emeka

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