Oral collagen in Panama: meta-analyses and supplement registration

In Panama, oral collagen is sold as powders, capsules and drinks promising firmer, better-hydrated skin, and many dermatology and aesthetic-medicine patients already take it. The physician's question has two halves: what the trials show, and how Panamanian regulation classifies a product that is swallowed. This article reviews the most-cited meta-analyses, the criticism they have received, and the framework of the Ministry of Health (Minsa) and the National Directorate of Pharmacy and Drugs (DNFD). It is information for scientific and regulatory analysis, not a recommendation for use. The general guide on the topic is Oral collagen: the peptide your patients already take.

What the three meta-analyses show in favor of oral collagen

The meta-analysis by de Miranda and colleagues (International Journal of Dermatology, 2021) pooled 19 studies with 1,125 participants aged 20 to 70, 95% women. It concluded that hydrolyzed collagen improved hydration, elasticity and wrinkles versus placebo, and that ingestion for 90 days is effective in reducing skin aging, according to its authors¹.

Pu and colleagues (Nutrients, 2023) analyzed 26 randomized trials with 1,721 patients. Hydrolyzed collagen significantly improved hydration and elasticity versus placebo, with hydration effects varying by collagen source and duration. The authors added that the study also identified several biases in the included trials². Dewi and colleagues (Cureus, 2023) gathered 14 studies with 967 participants, published between 2017 and 2023, and described improved hydration and elasticity with a 12-week regimen³.

In the randomized trial by Proksch and colleagues, 69 women aged 35 to 55 received collagen peptides or placebo for 8 weeks; skin elasticity improved significantly versus placebo, while moisture and water loss did not reach statistical significance, and no side effects were reported⁷.

The criticism: heterogeneity, bias and funding

The meta-analyses acknowledge their own limits. A comment published in the same journal as the de Miranda paper, by Peres and colleagues, questioned the heterogeneity of the studies included in that analysis⁴. Pu and colleagues pointed to biases in the trials they pooled².

The strongest criticism came in 2025. Myung and Park (The American Journal of Medicine) analyzed 23 trials with 1,474 participants. Overall, collagen supplements improved hydration, elasticity and wrinkles. But in the subgroup analysis, studies not funded by pharmaceutical companies showed no effect on any of the three outcomes, while industry-funded studies did; and high-quality studies showed no significant effect in any category. Their conclusion: there is currently no clinical evidence to support the use of collagen supplements to prevent or treat skin aging⁵.

For a physician talking to a patient, the prudent reading is that favorable trials exist and are numerous, but their quality and origin affect how much they weigh. An effect that appears in sponsored studies and fades in independent ones does not prove there is no effect, but it does require talking about uncertainty.

What is known about the mechanism

The biological basis is plausible, though it is not clinical proof. After ingesting hydrolyzed gelatin, hydroxyproline-containing peptides appear in human blood: in the Iwai study the peptide form of hydroxyproline peaked at 1 to 2 hours and the main component was prolyl-hydroxyproline⁸. In cultured mouse skin fibroblasts, that dipeptide stimulated cell growth in a dose-dependent way⁹. These are laboratory and pharmacokinetic data, not patient outcomes.

How a supplement is classified in Panama

Executive Decree 27 of May 10, 2024 (Gaceta Oficial Digital 30028-C) regulates Law 419 of 2024. Its article 208 says products that claim to cure a disease, or that can be ingested, inhaled or injected into the human body, are not considered cosmetic products, since cosmetics must only be applied topically¹⁰. The DNFD recalled that article in Note 010/SCV/DFV/DNFD-2024 on cosmetic safety¹¹. The practical consequence: a collagen powder or capsule cannot be registered or promoted as a cosmetic.

Article 61 of the same decree, in the chapter on the registration of dietary supplements with therapeutic properties, says the procedure and requirements for the health registration of vitamin, dietary and food supplements, according to the concentrations defined by internationally accredited reference bodies, shall be established by Executive Decree¹⁰. In other words, the text points to a later rule; it does not describe the procedure. A 2019 legal summary describes Resolution 550 of May 29, 2019, which regulated registration of supplements "with therapeutic properties"¹³; this article could not confirm with the DNFD whether it remains in force after Law 419 and Decree 27, so the DNFD should be consulted before assuming any requirement.

A February 2011 DNFD statement recalls that, under Law 1 of 2001, a dietary supplement in Panama is a substance or mixture of substances intended to complete the nutrients normally present in food, and that dietary supplements are not medicines¹². The decree does not name collagen; whether a specific product falls under DNFD authority depends on its formulation and what its label claims.

What happens with unregistered supplements

The risk is not theoretical. In October 2018, SENAFRONT seized 195 jars of "alleged food supplements" without health registration in Chiriquí and handed them to the Customs Prevention and Oversight Directorate¹⁴. More recently, the DNFD issued an alert on Artri Ajo Rey and Artri Ajo King, joint-pain products that do not have health registration in Panama; according to the FDA, cited by Minsa, Artri Ajo Rey contains dexamethasone, diclofenac and methocarbamol that do not appear on the label¹⁵. The case is detailed in Artri Ajo Rey in Panama. On how registration applies to aesthetics, see the double standard in aesthetic health registration and anti-aging peptides in Panama: a 19-trial meta-analysis.

What a physician can say today

• That meta-analyses of randomized trials show favorable results for hydration and elasticity, with regimens of roughly 12 to 13 weeks, and that their own authors point to biases¹²³.
• That a 2025 review found no effect in studies without industry funding or in high-quality studies⁵.
• That an ingestible product is not a cosmetic under Executive Decree 27 of 2024, and that any claim to cure a disease takes it out of that category¹⁰.
• That it is worth checking the specific product's registration with the DNFD, because the Artri Ajo Rey alert shows what happens when an ingestible product circulates without it¹⁵.