2. https://pubmed.ncbi.nlm.nih.gov/29949889/

Study Name: Oral intake of low-molecular-weight collagen peptide improves hydration, elasticity, and wrinkling in human skin.
Study class: Randomized, double-blind, placebo-controlled study.
Publication: Nutrients, 2018.10(7): p.826.
Authors: Kim, D.-U., et al

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3. https://pubmed.ncbi.nlm.nih.gov/33521019/

Study Name: Effect of collagen tripeptide and adjusting for climate change on skin hydration in middle-aged women.
Study class: A randomized, double-blind, placebo-controlled trial.
Publication: Frontiers in Medicine, 2021. 7: p.608903.
Authors: Tak, Y.J., et al.

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4.https://pubmed.ncbi.nlm.nih.gov/26840887/

Study Name: Ingestion of bioactive collagen hydrolysates enhance facial skin moisture and elasticity and reduce facial ageing signs.
Study class: A double-blind, placebo-controlled study.
Publication: Journal of the Science of Food and Agriculture, 2016. 96(12): p.4077-4081.
Authors: Inoue, N., F. Sugihara, and X. Wang.

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5.https://pubmed.ncbi.nlm.nih.gov/37822045/

Study Name: Low‐molecular‐weight collagen peptides supplement promotes a healthy skin.
Study class: A randomized, double‐blinded, placebo‐controlled study.
Publication: Journal of Cosmetic Dermatology, 2023.
Authors: Seong, S.H., et al.

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6.https://pmc.ncbi.nlm.nih.gov/articles/PMC6835901/

Study Name: A collagen supplement improves skin hydration, elasticity, roughness, and density.
Study class: A randomized, placebo-controlled, blind study.
Publication: Nutrients, 2019. 11(10): p.2494.
Authors: Bolke, L., et al.

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7.https://www.sciencedirect.com/science/article/pii/S1756464623004383

Study Name: The effect of a 12-week dietary intake of food supplements containing collagen and MSM on dermis density and other skin parameters.
Study class: A double-blind, placebo-controlled, randomised four-way study comparing the efficacy of three test products.
Publication: Journal of Functional Foods, 2023. 110: p.105838.
Authors: Pogačnik, T., et al.

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8. https://pubmed.ncbi.nlm.nih.gov/24401291/

Study Name: Oral intake of specific bioactive collagen peptides reduces skin wrinkles and increases dermal matrix synthesis.
Study class: A double-blind, placebo-controlled study.
Publication: Skin pharmacology and physiology, 2014. 27(3): p.113-119.
Authors: Proksch, E., et al.

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9.https://pubmed.ncbi.nlm.nih.gov/36916504/

Study Name: Oral intake of collagen peptide NS improves hydration, elasticity, desquamation, and wrinkling in human skin.
Study class: A randomized, double-blinded, placebo-controlled study.
Publication: Food & Function, 2023. 14(7): p.3196-3207.
Authors: Lee, M., et al.

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