# I keep skin-care hopes apart from an energy claim

[Peptides Blog](/) · [Archive](/#archive) · [Topics](/#topics) · [About](/about)

[Peptides Blog](/) / GHK-Cu and NAD+

October 27, 2026

An ingredient does something interesting inside the body. Does adding more help? GHK-Cu and NAD+ both bring me back to that question.

They’re different substances, too. GHK-Cu is a peptide holding copper. NAD+ is a coenzyme, a helper in the cell’s chemical reactions. It isn’t a peptide, even if it often turns up in the same conversation.

## Skin is the question for GHK-Cu

![Natural texture on an adult cheek and temple in soft side light.](/pb-quiet-morning-0e3fea6c17b1/skin-in-early-light.webp)

Skin texture is the subject; a cell-culture collagen result is a different kind of observation.

GHK-Cu is a chain of three amino acids, the building blocks of proteins, holding copper. It often appears on skin-care lists as copper tripeptide-1. An early [experiment in skin cells found more collagen production](https://pubmed.ncbi.nlm.nih.gov/3169264/). One job of the protein collagen is to give skin strength.

That study was in a dish. It explains why someone might want to test a cream, but it can’t tell us what happens on a face.

A [small trial after laser skin treatment](https://pubmed.ncbi.nlm.nih.gov/16847171/) couldn’t show a clear difference in redness or wrinkles between the groups with and without copper-peptide skin care. People using it did report more satisfaction. I want to keep both findings: people’s impressions matter, and a small study can leave a difference unresolved. Recently lasered skin is also a very particular setting.

Small topical studies can miss uncommon harms and don’t settle long-term safety. Injections raise a separate concern: FDA flags possible immune reactions and limited human safety information.

The injectable form of GHK-Cu appears under [nominations that were withdrawn](https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks) on the FDA safety page dated April 22, 2026. Requests were taken back; FDA didn’t clear it for compounding. That statement is about injections.

FDA also explains that [cosmetics generally don’t need approval before sale](https://www.fda.gov/cosmetics/cosmetics-laws-regulations/fda-authority-over-cosmetics-how-cosmetics-are-not-fda-approved-are-fda-regulated). Claims to treat disease or change how the body works can make something a drug. An ingredient’s place in skin care doesn’t establish it as an approved medicine.

## Energy is a different question for NAD+

![Illustrative microscopy-style view of folded membranes inside a cell’s mitochondria.](/pb-quiet-morning-0e3fea6c17b1/afternoon-in-progress.webp)

An illustrative look inside a cell, where NAD+ helps with energy reactions; it is no measure of how energetic someone feels.

NAD+ helps cells carry out reactions that release usable energy. That doesn’t, by itself, show that adding more gives someone a brighter afternoon.

NR, short for nicotinamide riboside, is material the body can use to make NAD+. An [oral NR trial raised blood NAD+ levels](https://pubmed.ncbi.nlm.nih.gov/31278280/). It tested a precursor, rather than an NAD+ infusion. A [review of human precursor studies found limited evidence of clinical benefit](https://pubmed.ncbi.nlm.nih.gov/41083806/), meaning improvements in people’s health.

The [oral NR trial lasted eight weeks and found no significant difference in side effects from placebo](https://pubmed.ncbi.nlm.nih.gov/31278280/). That leaves long-term safety unanswered, and it can’t establish safety for a different route. NAD+ infusions are not FDA-approved; [compounding doesn’t make them approved](https://www.fda.gov/drugs/human-drug-compounding/compounding-and-fda-questions-and-answers).

I’d keep these claims small enough to check. A skin claim needs skin results. An energy claim needs more than a blood test. Persistent skin or fatigue concerns are something a licensed U.S. clinician can assess, with room to discuss established options.

Publication note: published October 27, 2026; last revised October 27, 2026. General reading, with no individual treatment advice.

[Back to the published posts](/#archive)

---

I keep Peptides Blog a reading guide, with no medical practice, pharmacy service or goods for sale.

[References](/references) · [Contact](/contact)

© 2026 Peptides Blog