Zinc Carnosine

The verdict

Is Zinc Carnosine worth taking?

Zinc carnosine is a synthetic complex of zinc bonded to the dipeptide L-carnosine. It is insoluble in water, dissolves in stomach acid, and sticks to damaged gastric lining for roughly twice as long as soluble zinc. That adhesion is the whole mechanism, and it is the reason the compound exists.

It is a licensed pharmaceutical in Japan, approved in July 1994 under the brand Promac for one indication: gastric ulcer. The approved dose there is 150 mg per day, taken as 75 mg twice daily. Almost every supplement sold outside Japan contains 75 mg and presents it as a full day's dose. That is one half of the drug dose, and it is the one dose that came back null when the manufacturer tested it against placebo.

What it is sold for in the United States — leaky gut, general digestive repair, gut lining support — rests on eighteen healthy volunteers across two crossover trials from a single laboratory, in both cases against a deliberately applied insult. The one time anyone measured gut permeability in people who were not being challenged, nothing happened.

The bottom line. If you have a diagnosed gastric problem, or you are taking an anti-inflammatory that is hard on your stomach, 150 mg a day split into two doses is a defensible thing to try, and it has a thirty-year prescription record behind it in Japan. If you are taking 75 mg once a day for “gut health” in general, you are taking half the studied dose for a use the studies did not test. Graded Moderate, and the grade is carried entirely by the Japanese ulcer evidence.

What it does

What Zinc Carnosine does in the body

Gastric mucosal repair, ulcer healing, protection against drug-induced damage to the stomach lining, and adjunctive use alongside H. pylori eradication therapy. Those are the uses with clinical data behind them, and they are all in the upper digestive tract.

The mechanism is unusual enough to explain why the compound exists at all. Zinc L-carnosine — polaprezinc in Japan, where it is a prescription drug — is one zinc atom chelated to the dipeptide L-carnosine in a polymer chain. The complex is poorly soluble, which is the point: rather than dissolving and being absorbed, it is held to adhere to damaged mucosa and dissociate slowly at the site, releasing zinc where the tissue is injured. In cell and animal work it stabilizes the mucosal barrier, induces heat shock protein 70 and metallothionein, and scavenges free radicals.

That is a genuinely different proposition from swallowing zinc picolinate. It is also a proposition about contact, not circulation — the manufacturer's own filings state that carnosine is not detected in plasma after dosing and that the compound's activity has been attributed to its persistence in the gut with no systemic effects. Any benefit claimed for a tissue outside the digestive tract is not supported by the compound's own pharmacology.

The evidence

What the research actually shows

Moderate, and the grade is doing a lot of work. The evidence splits into two bodies that are routinely merged, and they do not support each other.

The Japanese ulcer evidence is real but it is a different product at a different dose. The pivotal phase III trial enrolled 299 patients with endoscopically confirmed gastric ulcer and compared polaprezinc 150 mg per day against cetraxate hydrochloride 800 mg per day. Endoscopic healing was 51.1 percent against 38.6 percent. There was no placebo arm anywhere in the approval package, the comparator was another Japanese mucosal protectant, and the package insert reports no statistical test for that difference. A late phase II dose-finding trial compared 100, 150 and 200 mg per day and found no significant difference between them on any endpoint, so no dose‐response for this compound on an ulcer outcome has ever been demonstrated in a human.

The gut-permeability evidence is eighteen people. Mahmood and colleagues, Gut 2007, randomized ten healthy volunteers in a crossover design, gave them indomethacin to deliberately damage the gut, and measured lactulose to rhamnose ratios. Davison and colleagues, American Journal of Clinical Nutrition 2016, did the same thing in eight volunteers using heavy exercise as the insult. Both trials come from the same research group. Neither has ever been replicated elsewhere, and the compound has never been tested in anyone with a diagnosed intestinal disease.

The sub-study nobody quotes. Inside the 2007 paper, four participants who were not given any NSAID took zinc carnosine for seven days. Their permeability ratios were 0.49 before treatment and 0.52 after. In people with an intact, unchallenged gut, it did nothing — and that is the population buying it.

Most of what gets cited as clinical from that paper is not. The 75 percent reduction in gastric damage is rats. The threefold increase in cell migration and proliferation is cell culture. Of six figures in the paper, two involve humans. The work was part-funded by Lonza Nutrition, which also supplied the test material and was the US distributor at the time.

The dose

The dose on the bottle is half the drug dose

Seventy-five milligrams is the number on almost every bottle. It is not a daily dose anywhere in the research. It is the unit dose of a Japanese prescription drug that is taken twice a day, after breakfast and at bedtime, for a total of 150 mg.

Worse, 75 mg per day has been tested against placebo, once, and it failed. Furihata and colleagues published an individual-patient-data meta-analysis in Nutrients in 2020, pooling four randomized placebo-controlled Japanese trials. Against placebo, the change in serum zinc was +2.60 µg/dL at 75 mg per day, with a 95 percent confidence interval of −5.93 to 11.12 and a p value of 0.52. At 150 mg it was +9.07 and significant. At 300 mg, +23.05. The 75 mg arm existed in only one of the four trials and was underpowered, which has to be said — but it is the only placebo-controlled test of the supplement dose that exists, and it is null. The first two authors and the corresponding author are employees of the company that makes the drug.

One more circularity worth knowing. The Gut 2007 researchers did not choose 37.5 mg twice daily from any pharmacology. They wrote that “the standard recommended dose is around 37.5 mg once or twice daily” and used what the supplement industry was already selling. Citing that trial as validation of the dose is an argument that closes on itself.

On zinc content: 75 mg of zinc carnosine supplies roughly 16 to 17 mg of elemental zinc. That is above the recommended intake, about 42 percent of the US tolerable upper limit of 40 mg, and about two-thirds of the EU upper limit of 25 mg. Take it twice daily as the drug label directs and you are over the EU limit and at 80 percent of the US one, before any multivitamin.

Where it goes

Does any of it reach your bloodstream?

No, and the people who make it say so in writing.

The Japanese regulatory dossier for Promac answers the question “therapeutically effective blood concentration” with: not applicable, because the drug acts directly and locally on the gastric mucosa. On plasma carnosine after dosing, the same document states that L-carnosine was not detected in plasma, and that amino acid concentrations did not differ from normal physiological values. Under absorption, distribution, metabolic pathway and first-pass effect, the dossier says no applicable data. The absolute bioavailability of zinc from this compound has never been determined in more than thirty years on the market.

What is measured is excretion. After a single 300 mg dose, 41.4 percent of the zinc was recovered in feces within 24 hours and 58.8 percent within 48. Urinary zinc recovery after 150 mg was 0.47 percent fasting and 0.12 percent after a meal — roughly four times less absorbed with food, which is how the label tells you to take it.

The applicant's own European dossier puts it plainly: the activity of zinc L-carnosine “has been attributed to its slow dissociation and persistent presence in the gut with no systemic effects.”

European regulators have assessed it twice and declined both times. The most recent opinion, adopted in May 2026, concluded that the compound is not sufficiently characterized, and that neither its bioavailability nor its safety can be established under the proposed conditions of use. It is not authorized for food supplements in the EU.

None of this means the compound does nothing. It means whatever it does, it does on contact with tissue, in the stomach, and not by circulating. Any claim that depends on it reaching a distant organ is unsupported by its own manufacturer's filings.

Food first

Getting Zinc Carnosine from food

You cannot get this compound from food. Zinc L-carnosine is a synthetic chelate — one zinc atom bound to one molecule of the dipeptide carnosine in a polymer chain. The European Commission classifies it as a structure that was not used as a food before May 1997, which is the legal definition of a novel food. Nothing you eat contains it.

What food gives you is the two parts separately, and that is worth knowing because the parts have their own evidence.

Carnosine is concentrated in skeletal muscle, so the richest sources are meat. Pork is the highest of the common meats at roughly 350 mg per 100 g, with beef around 150 to 250 mg and lamb similar. Poultry is lower in carnosine than the red meats because birds convert much of it to anserine, a methylated relative. Fish is lower again. There is effectively none in plants, which is why long-term vegetarians run lower muscle carnosine.

Zinc is a different map. Oysters are in a class of their own, and the species matters: eastern oysters run about 39 mg per 100 g against roughly 17 mg for Pacific oysters. Beef chuck and shank sit near 7 to 9 mg per 100 g, crab and lobster around 4 to 7, pumpkin seeds about 7.6, hemp seeds about 10. Legumes and whole grains carry zinc but also phytate, which binds it — soaking, sprouting and fermentation break phytate down and raise what you actually absorb.

So a plate of pork or beef with a side that is not phytate-heavy gets you both substrates at once. That is not the same as taking the chelate, and I am not going to claim it is. The chelate's proposed mechanism depends on the intact complex sitting on gastric tissue; eating the parts does not reconstitute it. What food does is keep muscle carnosine and zinc status where they should be, which is the foundation the supplement question sits on top of.

What the guide adds

The part that is not on this page

Copper deficiency is a listed serious adverse reaction. Not a theoretical interaction — it is on the Japanese drug label for this compound, alongside sideroblastic anemia and neutropenia, with instructions to monitor. Zinc and copper compete for the same intestinal transporter. At 150 mg twice daily you are taking roughly 33 mg of elemental zinc, which is above both the US and EU upper limits, and sustained intake at that level is the recognized cause of copper depletion. Anyone taking this for months should know that.

Twelve weeks is the longest controlled human exposure. Every trial of this compound runs 8 to 12 weeks at most. There is no controlled data on a year of continuous use, which is how supplements are actually taken.

The gut-permeability finding is eighteen people. Two crossover trials, both from the same research group, both in healthy volunteers, both needing a deliberate challenge to show anything. Mahmood and colleagues, Gut 2007, used indomethacin in ten people. Davison and colleagues, American Journal of Clinical Nutrition 2016, used heavy exercise in eight. The live version of this page dated that second trial to 2014 and described the participants as athletes; they were recreationally active healthy volunteers. Eighteen people in total, never replicated outside that group, and never tested in anyone with a diagnosed intestinal disease.

The reflux and ulcer evidence is Japanese, and mostly not placebo-controlled. The compound has been a prescription drug in Japan since 1994 with a real clinical record behind it, but the trials that established it were done at the drug dose, in patients with diagnosed gastric ulcer, and the modern work on functional dyspepsia and reflux is largely open-label or comparative rather than placebo-controlled.

No one has measured bioavailability. Thirty years on the market and the absolute bioavailability of zinc from this complex has never been determined. The manufacturer's own dossier lists no applicable data for absorption, distribution, metabolism and first-pass effect.

If you are taking it for a reason other than the stomach, the evidence does not reach. Wound healing, taste disturbance, immune support, skin: those are claims about zinc status generally, and if zinc status is the goal there are cheaper and better-characterized forms. The case for this specific compound is a local one, in the stomach, and that is where it should stay. If raising your zinc status is what you are after, start with the zinc entry instead — different forms, different question.

About the author

Who graded this

Daniel Edlund is a Le Cordon Bleu-trained private chef in Los Angeles, a certified personal trainer and strength coach, and an internationally licensed massage therapist. Thirty years of strength training and fifteen years cooking in private estate kitchens. He is the author of The Complete Supplement Guide, which grades 147 entries against the clinical literature, and of The EASY Way to Organic Cooking, first published in 2013.

More about Daniel →

This page is information, not medical advice. Supplements interact with prescription medication and with each other, and the right answer depends on your own bloodwork and history. Talk to your doctor before starting anything, particularly if you are pregnant, nursing, managing a health condition, or already taking medication.

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