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Collagen Tripeptide (Gly-Pro-Hyp Rich Collagen Peptide)

Evidence Level
Limited
7 Clinical Trials
5 Documented Benefits
2/5 Evidence Score

Collagen tripeptide is collagen broken down by enzymes into very small fragments, with a large share of three-amino-acid pieces that follow collagen's Gly-X-Y pattern, such as Gly-Pro-Hyp. Tested products, mostly from fish skin, list 15 to 20 percent tripeptides including about 3 percent Gly-Pro-Hyp, and Jellice of Japan sells grades listed at 15 and 50 percent. These products raised blood Gly-Pro-Hyp more than ordinary collagen peptides, a marker rather than a health outcome. In placebo-controlled trials of 1,000 mg a day, women had better skin hydration, elasticity and wrinkle scores in one trial, while a second found no difference in its main skin water loss measure until results were adjusted for weather. In adults with early knee joint wear, 3,000 mg a day for six months lowered a knee pain score more than placebo. Most trials were small and run or funded by the makers.

Studied Dose 1,000 mg a day for 12 to 24 weeks in skin trials; 3,000 mg a day (as 500 mg tablets) for 180 days in a knee trial; 3 g a day for 12 weeks in an early skin study; 16 g a day for 6 months in an open-label vascular study.
Active Compound Enzymatically hydrolyzed type I collagen with a high share of Gly-X-Y tripeptides, mainly Gly-Pro-Hyp. Tested products: a catfish skin peptide from Newtree (Korea) with over 15 percent tripeptides including 3 percent Gly-Pro-Hyp; Amicogen's tilapia skin Collagen-Tripep20S (20 percent tripeptides, 3.2 percent Gly-Pro-Hyp, average 500 Da); and Jellice (Japan) collagen tripeptide.

Benefits

Skin hydration and elasticity in women aged 40 to 60

In a placebo-controlled trial, 1,000 mg a day of a catfish collagen peptide with over 15 percent tripeptides gave higher skin hydration than placebo at 6 and 12 weeks and better scores on two of three elasticity measures at 12 weeks; 53 of 64 women finished. A second trial of a tilapia tripeptide at the same dose found no difference in hydration, elasticity or its main outcome, skin water loss, unless weather was adjusted for.

Supported by Trial 2, Trial 1

Facial wrinkle scores

In the catfish collagen peptide trial, dermatologist wrinkle grades and three of five wrinkle depth measures from skin replicas improved more than with placebo after 12 weeks of 1,000 mg a day. In the tilapia tripeptide trial, wrinkle grades and wrinkle measures did not differ from placebo. Both trials involved employees of the product makers.

Supported by Trial 1, Trial 2

Thigh skin smoothness, skin elasticity and hair thickness

In 114 women aged 20 to 50 with thigh cellulite and thinning hair, a fish collagen peptide rich in Gly-Pro-Hyp at 1,000 mg a day for 24 weeks improved cellulite severity, skin roughness and elasticity more than placebo at weeks 12 and 24, and hair diameter at week 24. Two of the five authors worked for Newtree, which makes this type of peptide.

Supported by Trial 3, Trial 1

Knee pain and physical function scores

In 80 adults aged 40 to 75 with early knee joint wear, 3,000 mg a day of a peptide with over 15 percent tripeptides for 180 days lowered the main outcome, a WOMAC knee pain score, more than placebo. Function and total scores also improved; a 100 mm pain scale, stiffness, joint space width and inflammation markers did not differ. Only 60 of 80 were analyzed. Funded by the maker, Newtree.

Supported by Trial 4

Arterial stiffness, a vascular marker

In an open-label study without a control group, 30 healthy adults took 16 g a day of Jellice collagen tripeptide for 6 months. An arterial stiffness index (CAVI) fell by about 0.2 points, and the LDL to HDL cholesterol ratio fell in those starting at 2.5 or higher. Two authors were Jellice employees. No placebo trial has tested this.

Supported by Trial 5

Mechanism of action

1

Tripeptides reach the blood intact

In a Jellice study in people, plasma Gly-Pro-Hyp and Pro-Hyp rose after collagen tripeptide preparations, and more with more Gly-Pro-Hyp eaten; both also appeared in urine. Other makers report similar higher blood Gly-Pro-Hyp than with ordinary collagen. Blood levels are a marker, not a health result.

2

Gly-Pro-Hyp as a signal to skin cells in the lab

In rats, Gly-Pro-Hyp and Pro-Hyp from a tripeptide product stayed stable in gut fluid and plasma for 2 hours, and Gly-Pro-Hyp crossed a layer of intestinal cells. In cultured human skin fibroblasts, Gly-Pro-Hyp limited the fall in collagen and elastin gene activity caused by oxidative stress. These are lab and animal findings, not trials in people.

3

How it differs from ordinary collagen peptides

Ordinary collagen peptides are mostly larger fragments. Tripeptide products are cut further by specific enzymes, such as a Bacillus collagenase for Amicogen's tilapia product, to keep intact Gly-X-Y units. No placebo-controlled trial found compares skin or joint outcomes of a tripeptide product head to head with an ordinary collagen peptide in healthy people.

Clinical trials

1
Catfish Collagen Peptide (15 Percent Tripeptides) 1,000 mg and Skin: 12 Week RCT
PubMed

Randomized, double-blind, placebo-controlled parallel trial; one 50 mL drink with 1,000 mg of low-molecular-weight collagen peptide (over 15 percent tripeptides including 3 percent Gly-Pro-Hyp, from Newtree) daily for 12 weeks; both drinks contained 100 mg vitamin C; no primary outcome named; per-protocol analysis; two authors from Newtree and one from Jellice; no external funding (Kim et al. 2018, Nutrients)

64 women aged 40 to 60 with crow's feet wrinkles randomized (33 test, 31 placebo); 53 completed.

Skin hydration was higher than placebo at 6 and 12 weeks. At 12 weeks the dermatologist wrinkle grade (p = 0.013) and three wrinkle replica measures (p = 0.043, 0.025 and 0.004) improved more than placebo, as did overall and net skin elasticity (p = 0.025 and 0.027). No adverse reactions were reported and blood and urine tests stayed normal.

2
Tilapia Collagen Tripeptide 1,000 mg and Skin Water Loss: 12 Week RCT
PubMed

Randomized, double-blind, placebo-controlled parallel trial; 1,000 mg a day of Collagen-Tripep20S (Amicogen; 20 percent tripeptides including 3.2 percent Gly-Pro-Hyp) or a maltodextrin and dextrin placebo for 12 weeks; registered NCT03505684 after enrollment began, with skin water loss (TEWL) as the primary outcome and no weather adjustment named; three authors employed by Amicogen (Tak et al. 2020, Front Med (Lausanne))

84 women aged 40 to 60 with raised skin water loss; 74 completed.

Primary outcome: at 12 weeks skin water loss fell more on collagen tripeptide (-0.94 versus -0.33 g/m2/h), but the unadjusted between-group test was not significant (p = 0.168); it was significant after adjustment for temperature, humidity and UV exposure (p = 0.024 to 0.032). The 6 week result did not differ. Hydration, elasticity and wrinkle measures did not differ from placebo.

3
Fish Collagen Peptide Rich in Gly-Pro-Hyp 1,000 mg: Cellulite, Skin and Hair RCT
PubMed

Randomized, placebo-controlled trial of 1,000 mg a day for 24 weeks, preceded by a preliminary blood study; low-molecular-weight collagen peptide from fish skin gelatin enriched in Gly-X-Y tripeptides; primary outcome not named in the abstract; blinding not described in the abstract; two of five authors from Newtree (Hwang et al. 2026, J Med Food)

114 women aged 20 to 50 with thigh cellulite and self-reported hair thinning.

Cellulite severity, the length of the skin and fat border, skin roughness and skin elasticity improved more than placebo at weeks 12 and 24, and hair diameter increased more at week 24. In the preliminary blood study, exposure to Gly-Pro-Hyp over 2 hours was about 54 times higher than after ordinary collagen.

4
Collagen Peptide (15 Percent Tripeptides) 3,000 mg and Knee Pain: 180 Day RCT
PubMed

Randomized, double-blind, placebo-controlled parallel trial; 3,000 mg a day (500 mg tablets) of a catfish skin peptide with over 15 percent tripeptides including at least 3 percent Gly-Pro-Hyp for 180 days; registered KCT0005507; funded by and product made by Newtree, with a Newtree employee as author; per-protocol analysis (Park et al. 2025, Front Nutr)

80 adults aged 40 to 75 with grade I or II knee osteoarthritis and knee pain; 60 analyzed (29 test, 31 placebo).

Primary outcome: WOMAC pain fell more than with placebo (-1.90 versus +0.61, p = 0.006). WOMAC function (p = 0.035) and total scores (p = 0.028) also improved more. The 100 mm pain scale (p = 0.299), stiffness, joint space width on X-ray and inflammation markers did not differ. One test participant left because of an adverse event (hives, judged unrelated); no serious events. The collagen group started with higher pain scores (4.45 versus 3.29) and more grade II knees, only per-protocol results were reported, and a published commentary questioned these points.

5
Jellice Collagen Tripeptide 16 g Daily and Arterial Stiffness: Open-Label Study
PubMed

Open-label, single-arm study without a control group; 16 g a day of Jellice collagen tripeptide (over 15 percent Gly-X-Y tripeptides) in two doses for 6 months; registered UMIN000018525; supported by a Japanese government small business subsidy; two authors employed by Jellice and one described as having been a Jellice board member (Tomosugi et al. 2017, J Atheroscler Thromb)

32 healthy adults (16 men, 16 women); 30 analyzed.

The cardio-ankle vascular index, an arterial stiffness marker, fell from baseline on both sides (p = 0.048 and 0.047), about 0.2 points. Advanced glycation end products in blood fell, and the LDL to HDL cholesterol ratio fell in people starting at 2.5 or higher. Without a placebo group, these changes cannot be attributed to the product.

6
Collagen Tripeptide 3 g With or Without Vitamin C and Skin: 12 Week Trial
PubMed

Randomized controlled trial with a no-supplement control group and no placebo; collagen peptide 3 g a day, collagen peptide 3 g plus vitamin C 500 mg, or vitamin C 500 mg alone for 12 weeks (Choi et al. 2014, J Cosmet Laser Ther)

32 healthy volunteers in four groups.

Changes in skin hydration and elasticity from baseline were greater in both collagen groups than in the no-supplement group. Adding vitamin C did not increase the effect. With about eight people per group and no placebo, the results are weak.

7
Jellice Collagen Tripeptide Absorption in Healthy People
PubMed

Human absorption study comparing a tripeptide fraction (CTP-100), a preparation with about 50 percent Gly-X-Y tripeptides (CTP-50) and a collagen peptide without tripeptides; all authors from Jellice (Yamamoto et al. 2016, Biol Pharm Bull)

Healthy volunteers (number not stated in the abstract).

Plasma Gly-Pro-Hyp and Pro-Hyp rose after both tripeptide preparations, more with more Gly-Pro-Hyp eaten, and both peptides appeared in urine. This shows absorption, a marker, and does not test any skin, joint or other health outcome.

Side effects and drug interactions

Common Potential side effects

In placebo-controlled skin trials of 1,000 mg a day for 12 weeks, no adverse reactions linked to the product were reported, and liver enzyme, kidney and glucose tests did not change.
In a 180 day trial of 3,000 mg a day, no serious adverse events occurred; one participant on the collagen peptide left the study because of an adverse event.
In a 6 month open-label study of 16 g a day, no adverse events were reported; one person stopped because of the taste.
The products tested were made from fish skin (catfish or tilapia) or other collagen sources. People with fish allergy should check the source listed on the label.
Published trials lasted 6 months or less, so longer-term safety has not been studied.

Important Drug interactions

No drug interaction studies of collagen tripeptide were found.
The skin trial excluded people who had used retinoids, steroids or other hormonal products in the prior 3 months, so effects alongside these medicines have not been studied. Ask a healthcare provider before combining it with prescription medicines.

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Frequently asked questions about Collagen Tripeptide (Gly-Pro-Hyp Rich Collagen Peptide)

How is collagen tripeptide different from regular collagen peptides?

Regular collagen peptides are mostly larger protein fragments. Collagen tripeptide is cut further with specific enzymes so that a larger share is three-amino-acid units such as Gly-Pro-Hyp; tested products list 15 to 20 percent tripeptides, and one Jellice grade is listed at 50 percent. Studies show more Gly-Pro-Hyp in the blood afterward, but no trial found compares skin or joint results head to head with regular collagen in healthy people.

How much collagen tripeptide was used in studies?

Skin trials used 1,000 mg a day for 12 to 24 weeks. A knee trial used 3,000 mg a day for 180 days, and an open-label vascular study used 16 g a day. Follow the product label and ask a healthcare provider for personal advice.

Does collagen tripeptide help skin?

Results are encouraging but not consistent. One placebo-controlled trial of 1,000 mg a day found better hydration, elasticity and wrinkle scores after 12 weeks, and another found better thigh skin texture after 24 weeks. A third trial found no difference in its main skin water loss measure until results were adjusted for weather, and no difference in hydration or wrinkles. The trials were small and involved the makers.

Has collagen tripeptide been studied for knee comfort?

One trial in 80 adults with early knee joint wear found that 3,000 mg a day for six months lowered a knee pain score more than placebo and improved function scores, while a separate pain scale, stiffness and X-ray joint space did not differ. The trial was funded by the maker and has not been repeated.

Is collagen tripeptide safe?

In trials lasting up to 6 months at 1,000 mg to 16 g a day, few side effects were reported and routine blood tests did not change. Products are often made from fish skin, so people with fish allergy should check the source. Longer-term safety has not been studied.

What is Collagen Tripeptide?

Collagen tripeptide is collagen broken down by enzymes into very small fragments, with a large share of three-amino-acid pieces that follow collagen's Gly-X-Y pattern, such as Gly-Pro-Hyp.

What is Collagen Tripeptide used for?

Collagen Tripeptide is researched primarily for Joint Health. In a placebo-controlled trial, 1,000 mg a day of a catfish collagen peptide with over 15 percent tripeptides gave higher skin hydration than placebo at 6 and 12 weeks and better scores on two of three elasticity measures at 12 weeks; 53 of…

Does Collagen Tripeptide interact with any medications?

Possible interactions include: No drug interaction studies of collagen tripeptide were found. The skin trial excluded people who had used retinoids, steroids or other hormonal products in the prior 3 months, so effects alongside these medicines have not been studied. If you take prescription medication, check with a pharmacist or doctor before using it.

How strong is the scientific evidence for Collagen Tripeptide?

NutraSmarts rates the evidence for Collagen Tripeptide as Limited (2 out of 5). It is backed by 7 study summaries and 13 cited references summarized on this page. A higher rating reflects more, larger, and better-designed human studies.

References(13 citations)

Evidence ratings on NutraSmarts are based on the totality of human clinical research, with emphasis on randomized controlled trials, meta-analyses, and systematic reviews. The references below directly support claims made throughout this page.

  1. Kim DU, Chung HC, Choi J, Sakai Y, Lee BY. Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study. Nutrients. 2018;10(7):826. doi: 10.3390/nu10070826.PubMedUsed to support: Randomized, double-blind, placebo-controlled trial in 64 women aged 40 to 60 (53 completed) of 1,000 mg a day of a catfish skin collagen peptide from Newtree with over 15 percent tripeptides including 3 percent Gly-Pro-Hyp, for 12 weeks; both drinks contained 100 mg vitamin C. Skin hydration was higher than placebo at 6 and 12 weeks, and wrinkle grade, three wrinkle replica measures and two of three elasticity measures improved more than placebo at 12 weeks. No adverse reactions. Authors from Newtree and Jellice; no external funding.
  2. Tak YJ, Shin DK, Kim AH, Kim JI, Lee YL, Ko HC, Kim YW, Lee SY. Effect of Collagen Tripeptide and Adjusting for Climate Change on Skin Hydration in Middle-Aged Women: A Randomized, Double-Blind, Placebo-Controlled Trial. Front Med (Lausanne). 2020;7:608903. doi: 10.3389/fmed.2020.608903.PubMedUsed to support: Randomized, double-blind, placebo-controlled trial (NCT03505684) in 84 women aged 40 to 60 of 1,000 mg a day of tilapia collagen tripeptide (Amicogen Collagen-Tripep20S, 20 percent tripeptides, 3.2 percent Gly-Pro-Hyp) for 12 weeks. The primary outcome, skin water loss, fell more than with placebo at 12 weeks only after adjustment for weather (p = 0.024 to 0.032); the unadjusted comparison (p = 0.168) and 6 week result did not differ. Hydration, elasticity and wrinkles did not differ from placebo. Three authors were Amicogen employees.
  3. Hwang S, Won J, Kim S, Kang W, Park M. Low-Molecular-Weight Collagen Peptide Supplementation Improves Cellulite Severity, Skin Elasticity, and Hair Shaft Diameter: A Clinical Study with Pharmacokinetic Evaluation. J Med Food. 2026;29(4):187-195. doi: 10.1177/1096620X261428336.PubMedUsed to support: A fish skin collagen peptide enriched in Gly-X-Y tripeptides, mainly Gly-Pro-Hyp, gave about 54 times higher 2 hour blood exposure to Gly-Pro-Hyp than ordinary collagen in a preliminary blood study. In a randomized, placebo-controlled trial in 114 women aged 20 to 50 with thigh cellulite and hair thinning, 1,000 mg a day for 24 weeks improved cellulite severity, skin roughness and elasticity at weeks 12 and 24 and hair diameter at week 24 more than placebo. Two authors were from Newtree.
  4. Park SY, Lee SH, Kim HT, Park HJ, Kim DU, Kim SU, Heo I. Efficacy and safety of low-molecular-weight collagen peptides in knee osteoarthritis: a randomized, double-blind, placebo-controlled trial. Front Nutr. 2025;12:1644899. doi: 10.3389/fnut.2025.1644899.PubMedUsed to support: Randomized, double-blind, placebo-controlled trial (KCT0005507) in 80 adults aged 40 to 75 with mild knee osteoarthritis of 3,000 mg a day for 180 days of a catfish skin collagen peptide standardized to over 15 percent tripeptides and at least 3 percent Gly-Pro-Hyp. The primary outcome, WOMAC pain, improved more than placebo (p = 0.006), as did function and total scores; the pain scale, stiffness, joint space width and inflammatory markers did not differ. Per-protocol analysis of 60; the collagen group started with higher WOMAC pain scores and more grade II knees. Funded by Newtree, which made the product.
  5. Tomosugi N, Yamamoto S, Takeuchi M, Yonekura H, Ishigaki Y, Numata N, Katsuda S, Sakai Y. Effect of Collagen Tripeptide on Atherosclerosis in Healthy Humans. J Atheroscler Thromb. 2017;24(5):530-538. doi: 10.5551/jat.36293.PubMedUsed to support: Open-label, single-arm 6 month study (UMIN000018525) in 32 healthy adults (30 analyzed) taking 16 g a day of Jellice collagen tripeptide. The cardio-ankle vascular index fell from baseline, as did advanced glycation end products, and the LDL to HDL cholesterol ratio fell in those starting at 2.5 or higher. No control group. No adverse events. Two authors were Jellice employees.
  6. Yamamoto S, Deguchi K, Onuma M, Numata N, Sakai Y. Absorption and Urinary Excretion of Peptides after Collagen Tripeptide Ingestion in Humans. Biol Pharm Bull. 2016;39(3):428-34. doi: 10.1248/bpb.b15-00624.PubMedUsed to support: Human absorption study by Jellice researchers comparing a tripeptide fraction, a preparation with about 50 percent Gly-X-Y tripeptides and a collagen peptide without tripeptides. Plasma Gly-Pro-Hyp and Pro-Hyp rose after the tripeptide preparations, more with more Gly-Pro-Hyp eaten, and were excreted in urine. An absorption marker study only.
  7. Choi SY, Ko EJ, Lee YH, Kim BG, Shin HJ, Seo DB, Lee SJ, Kim BJ, Kim MN. Effects of collagen tripeptide supplement on skin properties: a prospective, randomized, controlled study. J Cosmet Laser Ther. 2014;16(3):132-7. doi: 10.3109/14764172.2013.854119.PubMedUsed to support: Randomized controlled trial in 32 healthy volunteers comparing no supplement, collagen peptide 3 g, collagen peptide 3 g with vitamin C 500 mg, and vitamin C 500 mg daily for 12 weeks. Hydration and elasticity changes were greater in both collagen groups than in the no-supplement group, and vitamin C added nothing. No placebo group.
  8. Sontakke SB, Jung JH, Piao Z, Chung HJ. Orally Available Collagen Tripeptide: Enzymatic Stability, Intestinal Permeability, and Absorption of Gly-Pro-Hyp and Pro-Hyp. J Agric Food Chem. 2016;64(38):7127-33. doi: 10.1021/acs.jafc.6b02955.PubMedUsed to support: Lab and rat study with Amicogen authors. A collagen tripeptide made from fish scales with a Bacillus collagenase gave higher plasma Gly-Pro-Hyp and Pro-Hyp in rats than a high molecular weight collagen peptide; both were stable in gut fluid and rat plasma for 2 hours, and Gly-Pro-Hyp crossed an intestinal cell layer. Not a study in people.
  9. Chae M, Moon CY, Lim SH, Yamashita Y, Yamada H, Ide M, Park CW, Roh J, Kim W. Oral Ingestion of AP Collagen Peptide Leads to Systemic Absorption of Gly-Pro-Hyp, Alleviating H(2)O(2)-Induced Dermal Fibroblast Aging. J Med Food. 2023;26(5):299-306. doi: 10.1089/jmf.2022.K.0149.PubMedUsed to support: Absorption study (UMIN000047972) by Amorepacific and Pharma Foods International researchers: among the collagen peptides measured, only Gly-Pro-Hyp rose significantly more in blood after their AP collagen peptide than after a general collagen peptide or collagen. In cultured dermal fibroblasts, Gly-Pro-Hyp limited the oxidative stress-induced fall in collagen, elastin and fibronectin gene activity (lab finding).
  10. Jellice Pioneer Europe B.V. CollaTP® (HACP) product page Jellice Europe website. 2026;Accessed 2026. https://jellice.eu/products/hacp/.SourceUsed to support: Not PubMed-indexed; maker web page. Describes CollaTP® (HACP) as a low molecular weight collagen peptide made by enzymatic hydrolysis developed in Japan, with a minimum of 15 percent collagen tripeptides and an average molecular weight of about 1,300 Da, from type I collagen of farmed marine origin. No dose and no studies are cited.
  11. Jellice Pioneer Europe B.V. Collameta™ product page Jellice Europe website. 2026;Accessed 2026. https://jellice.eu/products/collameta/.SourceUsed to support: Not PubMed-indexed; maker web page. Describes Collameta™ as a high-concentration collagen tripeptide with 50 percent collagen tripeptides, average molecular weight about 500 Da, from type I marine collagen. No dose and no studies are cited.
  12. Montemarano M. Glanbia Nutritionals Launches High-Potency Collagen Tripeptide, Collameta Nutraceuticals World. 2024;June 6, 2024. https://www.nutraceuticalsworld.com/?p=42257.SourceUsed to support: Not PubMed-indexed; trade press article. Reports that Glanbia Nutritionals launched Collameta, a patented collagen tripeptide, with Jellice in North America in June 2024, described as 50 percent bioactive tripeptides at about 300 Da and used at about 500 to 1,000 mg a day. Absorption and efficacy statements in the article come from the company.
  13. Qiu J, Xiao F, Yang J. Commentary: Efficacy and safety of low-molecular-weight collagen peptides in knee osteoarthritis: a randomized, double-blind, placebo-controlled trial. Front Nutr. 2025;12:1712455. doi: 10.3389/fnut.2025.1712455.PubMedUsed to support: Published commentary on the knee trial of a low-molecular-weight collagen peptide. It notes a baseline imbalance in knee X-ray grades (77.4 percent grade I on placebo versus 51.7 percent on the collagen peptide), 25 percent attrition with a per-protocol analysis, sample size based on WOMAC total rather than the primary WOMAC pain score, and no difference on the pain scale, and calls for independent replication.