Peptides by goal: what works for what

Most people arrive knowing what they want, not which molecule to ask for. These pages start from the goal and work back to the compounds — and each one opens by stating what the evidence actually supports, including the goals where the honest answer is “less than you have been told”.

Peptides for muscle growth

Which peptides are marketed for building muscle, what human evidence exists for each, and why growth hormone secretagogues increase lean mass on a scale without reliably increasing strength.

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Peptides for anti-aging

Epitalon, NAD+, SS-31, GHK-Cu and MOTS-c are all sold for longevity. What has been shown in humans, what has only been shown in cells and mice, and what has been shown in neither.

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Peptides for weight loss

GLP-1 and dual agonist medications produce 15 to 22 percent weight loss in trials and are FDA-approved. Which are approved, which are investigational, and which marketed fat-loss peptides failed their trials.

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Peptides for injury & recovery

BPC-157 and TB-500 are the most searched healing peptides. The rodent data is genuinely striking and the human data is almost entirely absent. What that gap means before you spend money.

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Peptides for sexual function

PT-141 (bremelanotide) is FDA-approved for hypoactive sexual desire disorder in premenopausal women. What it does, who it was approved for, and how it differs from ED medications.

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Peptides for immune support

Thymosin alpha-1 is approved in many countries but not the United States. What the immune peptides do, where they are approved, and what the evidence supports.

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Peptides for growth hormone

How growth hormone secretagogues differ from injecting HGH, which are FDA-approved and for what, and what raising your growth hormone actually achieves.

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Peptides for skin & hair

GHK-Cu has the strongest human evidence of any cosmetic peptide. What topical versus injected use means, and what the collagen data actually shows.

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Peptides for energy & mitochondria

NAD+, MOTS-c and SS-31 all target mitochondrial function. What raising NAD+ has been shown to do, and what it has not.

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Peptides for gut health

BPC-157 and KPV are used for intestinal inflammation and leaky gut. The rodent evidence for gut healing, and why the human gap matters more here.

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Peptides for cognition & mood

Semax and Selank are registered medicines in Russia and unapproved elsewhere. Dihexa's core mechanism paper was retracted in 2025. What that means for readers.

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Peptides for sleep

Delta sleep-inducing peptide is the main compound sold for sleep. The evidence is small, dated and largely unreplicated, and it is not FDA-approved.

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Peptides for hormones & menopause

Where peptides fit alongside testosterone replacement and menopausal hormone therapy — and where they do not substitute for either.

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Medical Disclaimer: This content is for informational purposes only and should not be considered medical advice. Always consult with a qualified healthcare provider before beginning any peptide therapy treatment.