Why we grade peptide × outcome — not the molecule

When you ask whether BPC-157 "works," the only honest answer is: works for what? The same molecule has compelling animal evidence for tendon repair and almost none for anxiety. Semaglutide has overwhelming evidence for type 2 diabetes and emerging — but not yet established — evidence for substance use disorders. A single letter grade collapses that signal into noise.

This is why every peptide on Peptigrade gets graded against every outcome it has been studied for, separately. BPC-157 carries six different grades on its page — one per investigated use — and most peptides will end up with three to ten outcome grades each.

How a peptide × outcome grade is constructed

Every grade is a roll-up of six weighted sub-scores, each rated 1 to 5 with a written justification. The sub-scores are:

1. Mechanism understood. Do we know how the molecule produces the claimed effect at a molecular and physiological level? "Plausible" is not the same as "demonstrated."
2. Human studies (count + quality). How many controlled studies in humans exist? What are they powered for? Are they published in peer-reviewed venues?
3. Effect vs placebo. Among trials that had a placebo arm, how big is the placebo-adjusted effect, and how consistent is it?
4. Long-term safety data. What is the longest published exposure window in humans, and what does post-marketing surveillance look like?
5. Side effect profile. What adverse events have been reported, at what rates, and how serious?
6. Regulatory status. Has it been reviewed by FDA, EMA, or another major agency for the studied use? Is it banned by sport governing bodies?

The roll-up is not a simple average. The first three sub-scores carry more weight because efficacy and mechanism are what the grade is fundamentally about. Safety is necessary but not sufficient — a perfectly safe molecule with no demonstrable effect still earns a low grade.

Why blanket grades are misleading

Examine.com — which we admire and explicitly modeled some of our methodology on — assigns a single letter grade per supplement. That works reasonably well for vitamin C (most studied uses cluster within an evidence band) but works poorly for peptides, where mechanism, dose, and route can produce wildly different evidence quality across uses for the same molecule.

A blanket "C" for BPC-157 hides the fact that the tendon-healing evidence is reasonably strong in animal models while the anxiety evidence is essentially zero, and it also hides the fact that even the tendon-healing line is bottlenecked by the absence of a randomized human trial. A buyer who reads "C for BPC-157" and assumes "C for everything" is being misinformed by the rating system itself.

What a grade is — and what it isn't

A grade is a compressed summary of the published evidence as of the page's last-updated date. It is not:

• A recommendation that you take the peptide
• An assertion that the peptide is safe for you specifically
• A claim that the regulatory framework around the peptide is adequate
• A comment on whether the peptide is legally available where you live

It is also not a static document. Grades change when new high-quality evidence is published. Every page shows its last-updated date and the studies that triggered the most recent change.

Why we'll occasionally grade harshly

If a peptide is widely sold and widely promoted but supported only by single-lab animal data with no replication, we will say so in the rationale and grade accordingly. The credibility of every other grade on this site depends on us being willing to give an Epitalon or a TB-500 a D grade when the evidence supports it. Influencer claims do not move grades. Replicated, peer-reviewed human evidence does.

That is the whole game. Read accordingly.