Table 1.
Characteristics of the patients in the included studies.
| Author (Year) | Female/Male | Age Range | Time (Weeks) | Intervention (Origin) | Outcome Extracted |
|---|---|---|---|---|---|
| Proksch et al. (2014a) [18] | 60/0 | 35–55 | 8, 12 | 2.5 g HC/5 g HC (porcine) | Elasticity/hydration/trans-epidermal water loss (TEWL)/wrinkles |
| Proksch et al. (2014b) [38] | 107/0 | 45–65 | 8, 12 | 2.5 g collagen peptides | Wrinkles/biopsy/procollagen type/elastin/fibrillin |
| Yoon et al. (2014) [39] | 44/0 | >44 | 12 | 3 g HC (fish) | Procollagen type 1/fibrillin 1/metalloproteinases 1 and 12/biopsies/immunohistochemical staining |
| Di Cerbo et al. (2014) [40] | 30/0 | 40–45 | 4.5 | 372 mg HC | Cutaneous pH/hydration/sebum/elasticity/skin tone/elastin/elastase 2/fibronectin/hyaluronic acid/carbonyl proteins |
| Choi et al. (2014) [32] | 24/8 | 30–48 | 5 | 3 g collagen peptides | Skin hydration/elasticity/TEWL/erythema/satisfaction questionnaire |
| Sugihara, Inoue, and Wang (2015) [28] | 53/0 | 35–55 | 8 | 2.5 g HC (fish) | Hydration/elasticity/wrinkles |
| Campos et al. (2015) [29] | 60/0 | 40–50 | 12 | 10 g HC | Corneal stratum hydration/skin viscoelasticity/dermal echogenicity/high-resolution photography |
| Asserin et al. (2015) [30] | 134/0 | 40–65 | 8, 12 | 10 g HC (porcine)/10 g HC (fish) | Skin moisture/TEWL/dermal density/dermal echogenicity/dermal collagen fragmentation |
| Inoue, Sugihara, and Wang (2016) [34] | 80/0 | 35–55 | 8 | 2.5 g collagen peptides | Skin moisture/elasticity/wrinkles |
| Genovese, Corbo, and Sibilla (2017) [41] | 111/9 | 40–60 | 12 | 5 g HC | Elasticity/biopsies/subjective questionnaire |
| Koizumi et al. (2017) [27] | 71/0 | 30–60 | 12 | 3 g collagen peptides | Wrinkles/moisture/elasticity/blood tests (γ-glutamyltransferase, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, mean corpuscular volume, red blood cell, platelet, white blood cell, bilirubin, creatinine, total cholesterol, glucose, hemoglobin, hematocrit, alanine aminotransferase, aspartate aminotransferase, total protein and albumin) |
| Czajka et al. (2018) [42] | 120/0 | 21–70 | 12 | 4 g HC | Elasticity/biopsies/self-perception questionnaire |
| Kim (2018) [43] | 70/0 | 40–60 | 12 | 1000 mg collagen (fish) | Skin hydration/wrinkling/elasticity |
| Ito, Seki, and Ueda (2018) [31] | 17/4 | 30–50 | 8 | 10 g collagen peptides (fish) | Elasticity/moisture/TEWL/skin pH/spots/wrinkle/skin pores/texture/density/collagen score/growth hormone (GH), insulin-like growth factor-1 (IGF-1) |
| Bolke et al. (2019) [26] | 72/0 | >35 | 12, 16 | 2.5 g collagen peptides | Hydration/elasticity/wrinkles/skin density/subjective questionnaire |
| Schwartz et al. (2019) [35] | 113/0 | 36–59 | 12 | 0.6 g HC (chicken) | Erythema/hydration/TEWL/elasticity/wrinkles/dermal collagen/subjective questionnaire |
| Zmitek et al. (2020) [44] | 31/0 | 40–65 | 12 | 4 g HC (fish) | Dermal density and thickness/viscoelasticity/hydration/TEWL/wrinkles/moisture/dermal microrelief |
| Laing et al. (2020) [45] | 60/0 | 40–70 | 12 | 2.5 g collagen peptides | Dermal collagen fragmentation/subjective questionnaire |
| Sangsuwan and Asawanonda (2020) [37] | 36/0 | 50–60 | 4, 8 | 5 g HC | Elasticity |
| Nomoto and Iizaka (2020) [33] | 27/12 | >65 | 8 | 12 g collagen peptides | Stratum corneum hydration/elasticity |
| Ping (2020) [46] | 50/0 | 35–50 | 8 | 5.5 g collagen (fish) | Skin hydration/brightness/texture/crow’s feet/collagen content |
| Evans (2020) [47] | 50/0 | 45–60 | 12 | 10 g HC (fish) | Wrinkles/elasticity/self-reported appearance |
| Tak (2021) [48] | 84/0 | 40–60 | 12 | 1000 mg collagen tripeptides | Hydration/elasticity/wrinkles |
| Miyanaga (2021) [49] | 99/0 | 35–50 | 12 | 1 g HC/5 g HC | Skin water content/TEWL/elasticity/thickness |
| Jung (2021) [50] | 25/25 | 35–60 | 12 | 1000 mg collagen (fish) | Skin hydration/TEWL/texture/flexibility |
| Bianchi (2022) [51] | 52/0 | 40–60 | 8 | 5 g HC | Skin moisturization/elasticity/wrinkle depth |