Collagen Absorption: Forms, Food & Timing, Compared
Bottom line
B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off.We found 42 studies with usable absorption data for this supplement, 17 of them in people; every value below is copied from its paper and cited.
Hydrolyzed collagen / collagen peptides measured higher than undenatured / non-hydrolyzed collagen in the one human head-to-head study (grade B).
Collagen tripeptide (high-tripeptide) vs hydrolyzed collagen / collagen peptides: matched single-form studies only (grade C).
- Studies in database
- 42 (all full-text)
- Species
- 17 human, 15 rodent, 2 other animal, 8 in vitro
- Form comparison grades
- C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off. Collagen tripeptide (high-tripeptide) vs Hydrolyzed collagen / collagen peptidesB: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. Hydrolyzed collagen / collagen peptides vs Undenatured / non-hydrolyzed collagen
Educational information about published research; not medical advice. Not intended to diagnose, treat, cure or prevent any disease. Talk to a clinician before changing supplements, especially if pregnant, nursing or on medication.
Best-absorbed form
Draft — pending reviewer- Best-absorbed form in our data: Hydrolyzed collagen / collagen peptides (evidence grade B).
- Hydrolyzed collagen / collagen peptides measured higher than undenatured / non-hydrolyzed collagen in the one human head-to-head study (grade B).
- Caveat: this rests on one small study, so treat it as provisional.
Absorption evidence only, from the graded comparisons on this page. Not a recommendation to buy any product, not dosing advice, not medical advice.
25 of 42 studies are not in humans; each is labeled with a species badge.
Collagen forms compared
| Form | Lowest | Highest | Studies | PMIDs |
|---|---|---|---|---|
| Collagen tripeptide (high-tripeptide) | 0 | 191.42 | 1 | 28244315 |
| Hydrolyzed collagen / collagen peptides | 0.1 | 169.1 | 4 | 24767063, 34461513, 35662250, 42715523 |
n = number of human studies. Full values with doses, sources and citations are in the data tables below.
Form tags are matched automatically and need reviewer confirmation. Values are not normalized across studies.
Species (abstract screen): 17 human, 13 rodent, 2 other animal, 8 in vitro
40 studies (17 human) · show quotes
- Loading… Each study is also listed with its citation in Studies.
Collagen collagen tripeptide (high-tripeptide) vs hydrolyzed collagen / collagen peptides: which absorbs better?
Collagen tripeptide (high-tripeptide) vs hydrolyzed collagen / collagen peptides: matched single-form studies only (grade C). See the measured values →
Species (abstract screen): no studies
No relevant studies in our database address this question yet. We don't fill gaps with guesses.
Collagen hydrolyzed collagen / collagen peptides vs undenatured / non-hydrolyzed collagen: which absorbs better?
Hydrolyzed collagen / collagen peptides measured higher than undenatured / non-hydrolyzed collagen in the one human head-to-head study (grade B). See the measured values →
Species (abstract screen): no studies
No relevant studies in our database address this question yet. We don't fill gaps with guesses.
Should you take Collagen with food?
C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off.human + animal datahow we gradeSpecies (abstract screen): 1 human, 2 rodent, 1 other animal
Grade basis (abstract screen): Only one non-randomized human study. Auto-computed draft grade — pending reviewer review.
4 studies (1 human) · show quotes
- Loading… Each study is also listed with its citation in Studies.
Best time to take Collagen
Not graded: no comparable evidence yet. All grades are drafts pending reviewer sign-off.no datahow we gradeSpecies (abstract screen): no studies
Grade basis (abstract screen): No relevant studies in the database for this question.
No relevant studies in our database address this question yet. We don't fill gaps with guesses.
Collagen cost per mg calculator
Compare what you pay per mg of each form. Shows published ranges only; no dose recommendations.
FAQ
Which form of Collagen is best absorbed?
Best-absorbed form in our data: Hydrolyzed collagen / collagen peptides (evidence grade B). Hydrolyzed collagen / collagen peptides measured higher than undenatured / non-hydrolyzed collagen in the one human head-to-head study (grade B). Caveat: this rests on one small study, so treat it as provisional. See the evidence →
Is Collagen collagen tripeptide (high-tripeptide) better absorbed than hydrolyzed collagen / collagen peptides?
Collagen tripeptide (high-tripeptide) vs hydrolyzed collagen / collagen peptides: matched single-form studies only (grade C). See the evidence →
Is Collagen hydrolyzed collagen / collagen peptides better absorbed than undenatured / non-hydrolyzed collagen?
Hydrolyzed collagen / collagen peptides measured higher than undenatured / non-hydrolyzed collagen in the one human head-to-head study (grade B). See the evidence →
Should Collagen be taken with food?
We have 4 relevant studies in our database that mention food or fasting. See the evidence →
When is the best time to take Collagen?
We have no relevant studies in our database that mention timing. See the evidence →
Is this dosing advice?
No. We summarize published absorption research and compare prices. Talk to a clinician about what's right for you. See the evidence →
Answers summarize the data on this page.
Measured absorption data (full-text extraction)
60 papers read in full text, 42 with usable data (18 excluded as off-topic, reviews or off-target). 978 values extracted. Species: Human 17Rodent 15In vitro 8Other animal 2
Grades: draft — pending reviewer (Dr. Colin Reily). Directions are auto-parsed from author statements; values are copied exactly as printed, never converted or estimated.
Forms with measured values
| Form | Studies | Values | Absorption evidence grade | Species |
|---|---|---|---|---|
| Hydrolyzed collagen / collagen peptides | 22 | 518 | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. 8 human studies, total n=50, 5 randomized/crossover; median CV 67.3% across 3 matched set(s) (consistent) | Human×12Rodent×5In vitro×3Other animal×2 |
| Collagen tripeptide (high-tripeptide) | 5 | 299 | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. 3 human studies, total n=24, 3 randomized/crossover; median CV 32.6% across 3 matched set(s) (consistent) | Human×3Rodent×2 |
| Undenatured / non-hydrolyzed collagen | 2 | 18 | C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off. 2 human studies, total n=16, 2 randomized/crossover; consistency not evaluable (no matched set with ≥2 studies) | Human×2 |
Single-form studies count as evidence for that form. Form tags are keyword-matched from arm descriptions and need reviewer confirmation.
Head-to-head comparisons
C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off.Collagen tripeptide (high-tripeptide) vs Hydrolyzed collagen / collagen peptidescombined head-to-head + matched single-form grade
matched single-form evidence only. H2H: none (no direct comparison in extracted data); indirect: C (1 separated matched set(s), ≥1 studies per form, baseline correction not reported)
B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off.Hydrolyzed collagen / collagen peptides vs Undenatured / non-hydrolyzed collagencombined head-to-head + matched single-form grade
head-to-head only; no matched single-form separation. H2H: B (1 human studies (1 randomized/crossover); majority: first form higher (1 agree, 0 contradict)); indirect: none
| Study | Comparison | Parameter | Author-stated result | p |
|---|---|---|---|---|
| Human PMID 41788055 | A (LMWCP) vs B (general collagen), GPH Cmax and AUC | AUC | LMWCP > general collagen (Cmax, AUC0–2h, AUC0–∞) “approximately 55-fold (P < .0001) and 54-fold (P < .0001) higher, respectively, than those observed after general collagen ingestion” (Results p.4; Table 1) | <.0001 |
Cmax, Tmax and AUC by study arm (948 values)
| Study | Arm / form | Dose | Fed | n | Analyte | Param | Value | Units | Source |
|---|---|---|---|---|---|---|---|---|---|
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | sum of 4 collagen-specific AAs (Gly+Pro+Hyp+Hyl) (plasma) | AUC AUC0-8h | 6689.8 ± 216.9 (SEM) | mmol h/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | sum of 4 collagen-specific AAs (Gly+Pro+Hyp+Hyl) (plasma) | AUC AUC0-8h | 7150.4 ± 285.8 (SEM) | mmol h/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | sum of 4 collagen-specific AAs (Gly+Pro+Hyp+Hyl) (plasma) | Cmax | 865.6 ± 25.1 (SEM) | mmol/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | sum of 4 collagen-specific AAs (Gly+Pro+Hyp+Hyl) (plasma) | Cmax | 1000.2 ± 52.8 (SEM) | mmol/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | glycine (plasma) | AUC AUC0-8h | 3861.7 ± 175.6 (SEM) | µU h/mL | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | glycine (plasma) | AUC AUC0-8h | 3998.0 ± 175.6 (SEM) | µU h/mL | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | glycine (plasma) | Cmax | 511.6 ± 19.8 (SEM) | µU/mL | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | glycine (plasma) | Cmax | 568.7 ± 30.5 (SEM) | µU/mL | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | proline (plasma) | AUC AUC0-8h | 2406.3 ± 107.9 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | proline (plasma) | AUC AUC0-8h | 2686.2 ± 138.6 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | proline (plasma) | Cmax | 300.4 ± 11.9 (SEM) | g/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | proline (plasma) | Cmax | 359.8 ± 19.9 (SEM) | g/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxyproline (plasma) | AUC AUC0-8h | 395.3 ± 21.2 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxyproline (plasma) | AUC AUC0-8h | 437.3 ± 32.3 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxyproline (plasma) | Cmax | 63.7 ± 4.1 (SEM) | g/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxyproline (plasma) | Cmax | 76.6 ± 8.0 (SEM) | g/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxylysine (plasma) | AUC AUC0-8h | 26.5 ± 1.0 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxylysine (plasma) | AUC AUC0-8h | 28.9 ± 1.4 (SEM) | g h/L | Table 3 |
| Human 18707117 | 10 g CH powder dissolved in 100 mL water | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxylysine (plasma) | Cmax | 5.7 ± 0.3 (SEM) | g/L | Table 3 |
| Human 18707117 | 10 g CH in 100 mL FMP (Danone (fermented milk product)) | 10 g collagen hydrolysate (active compound) | fasted | 15 | hydroxylysine (plasma) | Cmax | 6.8 ± 0.5 (SEM) | g/L | Table 3 |
| Human 18707117 | blood amino acids (plasma) | Tmax time of peak blood AA concentration (text) | 1-1.5 | h | Discussion p.7793 | ||||
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 1 | 10.95 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 1 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 2 | 21.25 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 2 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 3 | 31.07 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 3 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 4 | 22.89 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 4 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, average of the four subjects' individual maxima | 21.53 | nmol/mL | Table 3 (Average row) |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 1 | 34.00 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 1 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 2 | 49.47 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 2 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 3 | 74.59 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 3 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 4 | 68.43 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 4 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, average of the four subjects' individual maxima | 56.87 | nmol/mL | Table 3 (Average row) |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 1 | 102.72 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 1 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 2 | 81.06 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 2 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 3 | 115.12 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 3 | 2 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, individual subject 4 | 87.95 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Tmax time of maximum level, individual subject 4 | 2 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 384.6 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | free Hyp (food-derived) (plasma) | Cmax maximum plasma level, average of the four subjects' individual maxima | 96.72 | nmol/mL | Table 3 (Average row) |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 1 | 18.45 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Tmax time of maximum level, individual subject 1 | 2 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 2 | 20.29 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Tmax time of maximum level, individual subject 2 | 0.25 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 3 | 8.53 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Tmax time of maximum level, individual subject 3 | 0.5 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 4 | 6.94 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Tmax time of maximum level, individual subject 4 | 2 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 30.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, average of the four subjects' individual maxima | 13.55 | nmol/mL | Table 3 (Average row) |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 1 | 19.85 | nmol/mL | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Tmax time of maximum level, individual subject 1 | 1 | h | Table 3 |
| Human 24767063 | cod (Gadus macrocephalus) skin gelatin enzymatic hydrolysate, mainly 1-5 kDa peptides (Yaizu Suisankagaku Industry (gift)) | 153.8 mg/kg body weight (active compound) | fasted 12 h; dissolved in 100 ml water | 4 | Hyp-containing peptides (total Hyp minus free Hyp) (plasma) | Cmax maximum plasma level, individual subject 2 | 19.91 | nmol/mL | Table 3 |
Showing 60 of 948 Cmax/Tmax/AUC values (human first). All 978 values are in /api/supplements/collagen.
References for this section (3)
- Human Walrand S, Chiotelli E, Noirt F, Mwewa S, Lassel T. Consumption of a functional fermented milk containing collagen hydrolysate improves the concentration of collagen-specific amino acids in plasma. Journal of agricultural and food chemistry. 2008;56(17):7790-5. PMID 18707117. doi:10.1021/jf800691f PubMed · DOI · randomized crossover (open; plasma analysis blinded), n=15
- Human Shigemura Y, Kubomura D, Sato Y, Sato K. Dose-dependent changes in the levels of free and peptide forms of hydroxyproline in human plasma after collagen hydrolysate ingestion. Food chemistry. 2014;159:328-32. PMID 24767063. doi:10.1016/j.foodchem.2014.02.091 PubMed · DOI · randomized crossover, n=4
- Human 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. Journal of medicinal food. 2026;29(4):187-195. PMID 41788055. doi:10.1177/1096620X261428336 PubMed · DOI · randomized crossover, n=8 (Study 1); 114 randomised (Study 2)
Indirect comparisons (across studies)
Each form's values come from different human studies that tested one form only. Rows are compared only when parameter, analyte, matrix, fed/fasted state, single vs repeated dosing, AUC interval and units all match, and baseline correction matches where reported (a value with baseline correction not reported is labeled and capped at grade D). Serum and plasma are treated as the same matrix. Ranges are the lowest and highest printed values; nothing is averaged or pooled. Conditions a paper does not state are recorded as NR and never matched.
Indirect comparison: weighs less than head-to-head evidence; comparisons using values with baseline correction not reported are capped at C. The combined grade for named pairs is shown in the head-to-head section. draft — pending reviewer (Dr. Colin Reily).
Indirect comparisonHydrolyzed collagen / collagen peptides vs Collagen tripeptide (high-tripeptide)D: animal or lab data only, or conflicting comparisons. All grades are drafts pending reviewer sign-off.baseline correction not reported
non-overlapping ranges but <2 studies per form (single-study ranges); uses value(s) with baseline correction not reported (capped at C under rubric v2). No head-to-head grade; indirect only.
| Matched conditions | Hydrolyzed collagen / collagen peptides: range (studies, n) | Collagen tripeptide (high-tripeptide): range (studies, n) | Ranges | PMIDs |
|---|---|---|---|---|
| Human Cmax, hyp-gly, serum/plasma, fasted, single dose, baseline-corrected: not reported baseline correction not reported (grade capped at C) values as printed (doses not normalized) | 8.7–10 nmol/ml 1 study, n=9 8.7 @ 10 g (PMID 34461513); 10.0 @ 10 g (PMID 34461513) | 0.7–1.58 nmol/ml 1 study, n=12 1.38 @ 300 mg/kg body weight in 20 w/v % water (PMID 28244315); 1.32 @ 300 mg/kg body weight in 20 w/v % water (PMID 28244315); 0.70 @ 900 mg/kg (PMID 28244315); 1.58 @ 1800 mg/kg (PMID 28244315) | do not overlap; Hydrolyzed collagen / collagen peptides higher | 2824431534461513 |
| Human Cmax, pro-hyp, serum/plasma, fasted, single dose, baseline-corrected: not reported baseline correction not reported (grade capped at C) values as printed (doses not normalized) | 21.1–22.9 nmol/ml 1 study, n=9 21.1 @ 10 g (PMID 34461513); 22.9 @ 10 g (PMID 34461513) | 14.42–72.73 nmol/ml 1 study, n=12 16.84 @ 300 mg/kg body weight in 20 w/v % water (PMID 28244315); 14.42 @ 300 mg/kg body weight in 20 w/v % water (PMID 28244315); 57.84 @ 900 mg/kg (PMID 28244315); 72.73 @ 1800 mg/kg (PMID 28244315); 18.35 @ 0.2 mmol/kg (PMID 28244315); 32.75 @ 0.2 mmol/kg (PMID 28244315) | overlap | 2824431534461513 |
Pairs that cannot be compared indirectly yet
- Hydrolyzed collagen / collagen peptides vs Undenatured / non-hydrolyzed collagen: matched only within the same study
- Collagen tripeptide (high-tripeptide) vs Undenatured / non-hydrolyzed collagen: matched only within the same study
How this table was built
Indirect (cross-study) PK comparisons from bundle_v2 single-form human arms. Values are copied as printed. Matching key: parameter, analyte, matrix, fed/fasted, single vs repeated, AUC interval (from parameter_detail), baseline correction, units (exact). No pooling/averaging: per-form ranges are min–max of printed values. Analyte for minerals/B12 is classed as total element vs isotope/radiotracer; units compared after removing spaces/separators only; IV arms excluded; serum and plasma treated as the same matrix; curated magnesium v1 rows (mapped from stated conditions only, NR otherwise, deduped against the bundle) are included; baseline correction NR is treated as unknown (may match corrected or uncorrected sets; labeled and capped at C); for % absorption endpoints an unreported baseline correction is treated as not applicable. Normalization: value / elemental dose (mg) ONLY when dose_basis is 'elemental', dose unit is mg, single dose, baseline-corrected=yes, parameter Cmax/AUC. Grade capped at C. Run after merge_bundle.py.
Evidence grades
Rubric v2: single-form human studies count. Hover or focus a grade for what it means; see the methodology. All grades are drafts pending reviewer sign-off.
| Question | Grade & basis | Species |
|---|---|---|
| Page grade (best of the grades below) | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. | rubric v2, draft |
| Hydrolyzed collagen / collagen peptides: absorption evidence | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. 8 human studies, total n=50, 5 randomized/crossover; median CV 67.3% across 3 matched set(s) (consistent) | human |
| Collagen tripeptide (high-tripeptide): absorption evidence | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. 3 human studies, total n=24, 3 randomized/crossover; median CV 32.6% across 3 matched set(s) (consistent) | human |
| Undenatured / non-hydrolyzed collagen: absorption evidence | C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off. 2 human studies, total n=16, 2 randomized/crossover; consistency not evaluable (no matched set with ≥2 studies) | human |
| Collagen tripeptide (high-tripeptide) vs Hydrolyzed collagen / collagen peptides | C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off. matched single-form evidence only. H2H: none (no direct comparison in extracted data); indirect: C (1 separated matched set(s), ≥1 studies per form, baseline correction not reported) | human (head-to-head + matched single-form) |
| Hydrolyzed collagen / collagen peptides vs Undenatured / non-hydrolyzed collagen | B: solid human data. Forms: 3+ human studies. Comparisons: one randomized head-to-head, or matched single-form evidence from 2+ studies per form. All grades are drafts pending reviewer sign-off. head-to-head only; no matched single-form separation. H2H: B (1 human studies (1 randomized/crossover); majority: first form higher (1 agree, 0 contradict)); indirect: none | human (head-to-head + matched single-form) |
| With food (abstract screen) | C: limited or conflicting human data: 1–2 studies, head-to-head and single-form evidence disagree, or baseline correction not reported. All grades are drafts pending reviewer sign-off.human + animal datahow we grade Only one non-randomized human study. Auto-computed draft grade — pending reviewer review. | 1 human, 2 rodent, 1 other animal |
| Best time (abstract screen) | Not graded: no comparable evidence yet. All grades are drafts pending reviewer sign-off.no datahow we grade No relevant studies in the database for this question. | no studies |
Studies (42)
Sorted human → primate → pig → rodent → other animal → in vitro. Quotes are verbatim from the abstract or free full text. Paywalled papers: abstract only.
Show all 42 studies and quotes
- HumanLow-Molecular-Weight Collagen Peptide Supplementation Improves Cellulite Severity, Skin Elasticity, and Hair Shaft Diameter: A Clinical Study with Pharmacokinetic Evaluation.Journal of medicinal food, 2026 · Design: randomized crossover · n: 8 (Study 1); 114 randomised (Study 2) · full text (PDF extraction) · open access: noPMID 41788055DOI 10.1177/1096620X261428336Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- HumanEnhanced digestion and absorption kinetics of ultra-low molecular weight collagen containing di- and tripeptides: evidence from human and cell models.PeerJ, 2026 · Design: parallel (randomized, single-blind exploratory pilot, 3 groups) plus in vitro Caco-2 · n: 15 · full text (PDF extraction) · open access: yesPMID 42609988DOI 10.7717/peerj.21398 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- HumanOral Ingestion of Jellyfish Collagen Hydrolysate Effectively Delivers a Bioactive Tripeptide, Gly-3Hyp-4Hyp, into the Blood and Skin.Journal of agricultural and food chemistry, 2026 · Design: parallel (two groups, human) plus mouse PK study · n: 17 humans · full text (PDF extraction) · open access: noPMID 42715523DOI 10.1021/acs.jafc.6c08326Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- HumanEffects of resistance exercise, collagen ingestion and circulating oestrogen concentration on collagen synthesis in a female athlete: A case report.Experimental physiology, 2025 · Design: randomized crossover (double-blind case study) · n: 1 · full text (PDF extraction) · open access: yesPMID 38984642DOI 10.1113/EP091897 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending10 verbatim quotes · view in JSON
- HumanThe Collagen Synthesis Response to an Acute Bout of Resistance Exercise Is Greater when Ingesting 30 g Hydrolyzed Collagen Compared with 15 g and 0 g in Resistance-Trained Young Men.The Journal of nutrition, 2024 · Design: randomized crossover · n: 10 (13 volunteered, 3 excluded before participation) · full text (PDF extraction) · open access: yesPMID 38007183DOI 10.1016/j.tjnut.2023.10.030 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending10 verbatim quotes · view in JSON
- HumanHydrolyzed collagen supplementation prior to resistance exercise augments collagen synthesis in a dose-response manner in resistance-trained, middle-aged men.American journal of physiology. Endocrinology and metabolism, 2024 · Design: randomized crossover · n: 8 · full text (PDF extraction) · open access: noPMID 39259166DOI 10.1152/ajpendo.00252.2024Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending10 verbatim quotes · view in JSON
- HumanOral Ingestion of AP Collagen Peptide Leads to Systemic Absorption of Gly-Pro-Hyp, Alleviating H(2)O(2)-Induced Dermal Fibroblast Aging.Journal of medicinal food, 2023 · Design: randomized crossover · n: 8 · full text (PDF extraction) · open access: noPMID 37074675DOI 10.1089/jmf.2022.K.0149Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending8 verbatim quotes · view in JSON
- HumanComparison of gelatin and low-molecular weight gelatin hydrolysate ingestion on hydroxyproline (Hyp), Pro-Hyp and Hyp-Gly concentrations in human blood.Food chemistry, 2022 · Design: randomized crossover · n: 9 · full text (PDF extraction) · open access: noPMID 34461513DOI 10.1016/j.foodchem.2021.130869Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending8 verbatim quotes · view in JSON
- HumanIdentification of a highly stable bioactive 3-hydroxyproline-containing tripeptide in human blood after collagen hydrolysate ingestion.NPJ science of food, 2022 · Design: other (human single-dose time-course; mouse parallel oral administration; in vitro plasma stability and cell assays) · n: Human 8; mouse 5 per group · full text (PDF extraction) · open access: yesPMID 35662250DOI 10.1038/s41538-022-00144-4 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- HumanNon-targeted and targeted analysis of collagen hydrolysates during the course of digestion and absorption.Analytical and bioanalytical chemistry, 2020 · Design: other (single-dose serum sampling; plus in vitro TIM digestion model) · n: 12 · full text (PDF extraction) · open access: yesPMID 31872275DOI 10.1007/s00216-019-02323-x (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending1 verbatim quote · view in JSON
- HumanAmount of Collagen in the Meat Contained in Japanese Daily Dishes and the Collagen Peptide Content in Human Blood after Ingestion of Cooked Fish Meat.Journal of agricultural and food chemistry, 2019 · Design: randomized crossover (randomization not stated; same volunteers received both) · n: 6 · full text (PDF extraction) · open access: noPMID 30784272DOI 10.1021/acs.jafc.8b06896Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending6 verbatim quotes · view in JSON
- HumanHuman Enriched Serum Following Hydrolysed Collagen Absorption Modulates Bone Cell Activity: from Bedside to Bench and Vice Versa.Nutrients, 2019 · Design: other (single-dose kinetic step then enriched-serum collection; mouse gavage kinetics) · full text (PDF extraction) · open access: yesPMID 31159319DOI 10.3390/nu11061249 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- HumanOral Ingestion of Collagen Hydrolysate Leads to the Transportation of Highly Concentrated Gly-Pro-Hyp and Its Hydrolyzed Form of Pro-Hyp into the Bloodstream and Skin.Journal of agricultural and food chemistry, 2017 · Design: Human: single-blinded randomized(not stated) crossover with ≥7 days washout; mouse: parallel dose groups, 5 mice per time point · n: 12 (human); mouse 5 per time point · full text (PDF extraction) · open access: noPMID 28244315DOI 10.1021/acs.jafc.6b05679Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- HumanAbsorption and Urinary Excretion of Peptides after Collagen Tripeptide Ingestion in Humans.Biological & pharmaceutical bulletin, 2016 · Design: randomized crossover · n: 4 · full text (PDF extraction) · open access: noPMID 26934933DOI 10.1248/bpb.b15-00624Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending10 verbatim quotes · view in JSON
- HumanDose-dependent changes in the levels of free and peptide forms of hydroxyproline in human plasma after collagen hydrolysate ingestion.Food chemistry, 2014 · Design: randomized crossover · n: 4 · full text (PDF extraction) · open access: noPMID 24767063DOI 10.1016/j.foodchem.2014.02.091Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- HumanHighly accurate quantification of hydroxyproline-containing peptides in blood using a protease digest of stable isotope-labeled collagen.Journal of agricultural and food chemistry, 2014 · Design: single-arm · n: 1 · full text (PDF extraction) · open access: noPMID 25417748DOI 10.1021/jf5039597Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- HumanConsumption of a functional fermented milk containing collagen hydrolysate improves the concentration of collagen-specific amino acids in plasma.Journal of agricultural and food chemistry, 2008 · Design: randomized crossover (open; plasma analysis blinded) · n: 15 · full text (PDF extraction) · open access: noPMID 18707117DOI 10.1021/jf800691fVerification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending5 verbatim quotes · view in JSON
- RodentComparative study of the therapeutic effects of sturgeon collagen peptide chelate-zinc on osteoarthritis induced by anterior cruciate ligament transection and medial meniscectomy in obese male rats.Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie, 2025 · Design: parallel · n: NR (text states 49 rats; groups n = 7 per figure/table captions) · full text (PDF extraction) · open access: noPMID 40517554DOI 10.1016/j.biopha.2025.118236Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentStability and iron affinity of Donkey-hide gelatin hydrolysates: Implications for improving iron bioavailability and gut microbiota modulation.NPJ science of food, 2025 · Design: parallel · n: 54 (CON 9 + MOD 45) · full text (PDF extraction) · open access: yesPMID 41298488DOI 10.1038/s41538-025-00617-2 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending5 verbatim quotes · view in JSON
- RodentPharmacokinetics of collagen dipeptides (Gly-Pro and Pro-Hyp) and tripeptides (Gly-Pro-Hyp) in rats.Journal of food science, 2024 · Design: other (parallel groups, IV and intragastric, 5 rats per subgroup) · n: 30 (PK); 15 (urinary excretion) · full text (PDF extraction) · open access: noPMID 38051020DOI 10.1111/1750-3841.16871Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending7 verbatim quotes · view in JSON
- RodentEffects of collagen hydrolysates on UV-induced photoaging mice: Gly-Pro-Hyp as a potent anti-photoaging peptide.Food & function, 2024 · Design: other (parallel oral PK in rats; separate mouse efficacy study) · n: 12 rats (6 per hydrolysate) · full text (PDF extraction) · open access: noPMID 38411396DOI 10.1039/d3fo04949cVerification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentEffect of Collagen Peptide-Chelated Zinc Nanoparticles From Pufferfish Skin on Zinc Bioavailability in Rats.Journal of medicinal food, 2021 · Design: parallel · n: 40 · full text (PDF extraction) · open access: noPMID 34448624DOI 10.1089/jmf.2021.K.0038Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentOrally administered collagen peptide protects against UVB-induced skin aging through the absorption of dipeptide forms, Gly-Pro and Pro-Hyp.Bioscience, biotechnology, and biochemistry, 2019 · Design: single-arm · n: 5 · full text (PDF extraction) · open access: noPMID 30739561DOI 10.1080/09168451.2019.1580559Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending5 verbatim quotes · view in JSON
- RodentAbsorption and metabolism of orally administered collagen hydrolysates evaluated by the vascularly perfused rat intestine and liver in situ.Biomedical research (Tokyo, Japan), 2018 · Design: parallel (collagen hydrolysate vs water control) with in situ vascular perfusion · full text (PDF extraction) · open access: noPMID 29467346DOI 10.2220/biomedres.39.1Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentIdentification of Collagen-Derived Hydroxyproline (Hyp)-Containing Cyclic Dipeptides with High Oral Bioavailability: Efficient Formation of Cyclo(X-Hyp) from X-Hyp-Gly-Type Tripeptides by Heating.Journal of agricultural and food chemistry, 2017 · Design: parallel (hydrolysate: control vs heat-treated; synthetic: two peptide-mixture groups) · full text (PDF extraction) · open access: noPMID 28988478DOI 10.1021/acs.jafc.7b03714Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending6 verbatim quotes · view in JSON
- RodentEfficient Absorption of X-Hydroxyproline (Hyp)-Gly after Oral Administration of a Novel Gelatin Hydrolysate Prepared Using Ginger Protease.Journal of agricultural and food chemistry, 2016 · Design: parallel (three groups, single oral gavage; comparison vs control hydrolysate PTC-GH) · full text (PDF extraction) · open access: noPMID 26978646DOI 10.1021/acs.jafc.6b00609Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- RodentOrally Available Collagen Tripeptide: Enzymatic Stability, Intestinal Permeability, and Absorption of Gly-Pro-Hyp and Pro-Hyp.Journal of agricultural and food chemistry, 2016 · Design: parallel (three oral groups); plus in vitro stability and Caco-2 assays · full text (PDF extraction) · open access: noPMID 27573716DOI 10.1021/acs.jafc.6b02955Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentDetermination of bioavailability and identification of collagen peptide in blood after oral ingestion of gelatin.Journal of the science of food and agriculture, 2015 · Design: parallel · n: 30 (PK experiment) + 20 (peptide identification experiment) · full text (PDF extraction) · open access: noPMID 25410396DOI 10.1002/jsfa.7008Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending5 verbatim quotes · view in JSON
- RodentBioavailability and bioavailable forms of collagen after oral administration to rats.Journal of agricultural and food chemistry, 2015 · Design: parallel · n: 30 (PK experiment) + 20 (peptide identification experiment) · full text (PDF extraction) · open access: noPMID 25826015DOI 10.1021/jf5057502Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- RodentAbsorption and plasma kinetics of collagen tripeptide after peroral or intraperitoneal administration in rats.Bioscience, biotechnology, and biochemistry, 2015 · Design: parallel · n: 13 (PK: 5 + 5 + 3) · full text (PDF extraction) · open access: noPMID 26155906DOI 10.1080/09168451.2015.1062711Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- RodentAbsorption and effectiveness of orally administered low molecular weight collagen hydrolysate in rats.Journal of agricultural and food chemistry, 2010 · Design: parallel · n: 48 (Wistar, Experiment 1) · full text (PDF extraction) · open access: noPMID 19957932DOI 10.1021/jf9031487Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- RodentAbsorption of hydroxyproline-containing peptides in vascularly perfused rat small intestine in situ.Bioscience, biotechnology, and biochemistry, 2009 · Design: other (specify): in situ vascularly perfused rat small intestine; single injection into jejunum · full text (PDF extraction) · open access: noPMID 19661700DOI 10.1271/bbb.90050Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending10 verbatim quotes · view in JSON
- Other animalFree Plasma Amino Acid Concentrations in Horses Fed Different Dosing Regimens of Hydrolysed Collagen.Animals : an open access journal from MDPI, 2025 · Design: randomized crossover · n: 6 · full text (PDF extraction) · open access: yesPMID 41227525DOI 10.3390/ani15213195 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending7 verbatim quotes · view in JSON
- Other animalChicken skin-derived collagen peptides chelated zinc promotes zinc absorption and represses tumor growth and invasion in vivo by suppressing autophagy.Frontiers in nutrition, 2022 · Design: other (animal feeding experiment) · full text (PDF extraction) · open access: yesPMID 35990359DOI 10.3389/fnut.2022.960926 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- In vitroComparative assessment on osteoprotective effects of bone collagen peptides from diverse animal sources: Insights from the characteristics of gastrointestinal digestion and absorption.Journal of the science of food and agriculture, 2026 · Design: other (in vitro digestion and Caco-2 transport; rat OVX efficacy study) · full text (PDF extraction) · open access: yes (free in PMC)PMID 42233495DOI 10.1002/jsfa.70759 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending3 verbatim quotes · view in JSON
- In vitroProduction of collagen-derived hydroxyproline (Hyp)-containing di- and tripeptides by brush border membrane enzymes and their absorption characteristics.Food research international (Ottawa, Ont.), 2025 · Design: other (in vivo rat PK + in vitro) · n: 12 rats (6 per hydrolysate) · full text (PDF extraction) · open access: noPMID 40597548DOI 10.1016/j.foodres.2025.116847Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending5 verbatim quotes · view in JSON
- In vitroDeer Skin Collagen Peptides Bound to Calcium: In Vitro Gastrointestinal Simulation of Digestion, Cellular Uptake and Analysis of Antioxidant Activity.Nutrients, 2024 · Design: other (in vitro) · full text (PDF extraction) · open access: yesPMID 39203724DOI 10.3390/nu16162585 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending2 verbatim quotes · view in JSON
- In vitroCollagen Peptides as a Hypoxia-Inducible Factor-2α-Stabilizing Prolyl Hydroxylase Inhibitor to Stimulate Intestinal Iron Absorption by Upregulating Iron Transport Proteins.Journal of agricultural and food chemistry, 2022 · Design: other (in vitro cell experiments and acute rat dosing) · n: 30 rats · full text (PDF extraction) · open access: noPMID 36475394DOI 10.1021/acs.jafc.2c05411Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending2 verbatim quotes · view in JSON
- In vitroThree Newly Isolated Calcium-Chelating Peptides from Tilapia Bone Collagen Hydrolysate Enhance Calcium Absorption Activity in Intestinal Caco-2 Cells.Journal of agricultural and food chemistry, 2020 · Design: other (in vitro Caco-2 transport) · full text (PDF extraction) · open access: noPMID 31927882DOI 10.1021/acs.jafc.9b07602Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
- In vitroThe in vitro bioavailability of anti-platelet peptides in collagen hydrolysate from silver carp (Hypophthalmichthys molitrix) skin.Journal of food biochemistry, 2020 · Design: other (in vitro digestion and Caco-2) · full text (PDF extraction) · open access: noPMID 32266991DOI 10.1111/jfbc.13226Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending1 verbatim quote · view in JSON
- In vitroNovel Hyp-Gly-containing antiplatelet peptides from collagen hydrolysate after simulated gastrointestinal digestion and intestinal absorption.Food & function, 2020 · Design: other (in vitro digestion/Caco-2; rat single-dose absorption) · full text (PDF extraction) · open access: noPMID 32520033DOI 10.1039/d0fo00219dVerification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending2 verbatim quotes · view in JSON
- In vitroCharacterization of Whey-Based Fermented Beverages Supplemented with Hydrolyzed Collagen: Antioxidant Activity and Bioavailability.Foods (Basel, Switzerland), 2020 · Design: other (in vitro digestion/dialysis) · full text (PDF extraction) · open access: yesPMID 32806694DOI 10.3390/foods9081106 (free full text)Verification: values extracted verbatim from the full-text PDF (bundle 2, 2026-11-02); reviewer check pending4 verbatim quotes · view in JSON
Reviewer
PhD, molecular pathology (UAB); BS, molecular biology & biochemistry (St. Olaf College). Reviews the science and evidence (not medical advice).
Draft, pending sign-off Next review: set at sign-off
Animal and lab findings are labeled and never presented as proof of effects in people. Claims are limited to what the cited studies report. See our methodology.