Daily oral supplementation of collagen peptides, when combined with vitamins and other bioactive ingredients, increases skin elasticity and has a positive effect on joint health and overall health.
Anna Czajka et al. Nutr Res. 2018 Sep.

In a double-blind, randomized, placebo-controlled clinical trial, participants taking a daily oral supplement experienced a significant increase in skin elasticity and improvement in joint health, which may be an effective solution to slow the signs of aging (Czajka et al., 2018).

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Oral Supplementation of Low Molecular Weight Collagen Peptides Reduces Skin Wrinkles and Improves Biophysical Properties of the Skin: A Randomized, Double-Blind, Placebo-Controlled Study
Jemin Kim et al. J Med Food. 2022 Dec.

This study showed that orally taken low molecular weight collagen peptides can contribute to antiaging by replacing extracellular matrix proteins that are degraded due to photoaging and can improve wrinkles, elasticity, moisture and barrier integrity of photoaged facial skin (Kim et al., 2022).

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Efficacy of Dietary Supplement for Skin Moisturization in Healthy Adults: Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Qian Sun et al. Front Nutr. 2022.

This review and meta-analysis study showed that nutritional supplements such as oral collagen, ceramide, hyaluronan, and procyanidin are effective on skin moisturizing, but noted that there is insufficient clear evidence about the effectiveness of other supplements (Sun et al., 2022).

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Oral intake of enzymatically cleaved AP collagen peptides increases skin moisture and ceramide and natural moisturizing factor content in the stratum corneum.
Kyoungmi Jung et al. Nutrients. 2021.

This study shows that oral intake of enzymatically cleaved AP collagen peptides (APCPs) can increase skin moisture and barrier function by assessing changes in stratum corneum (SC) components, which are among the aims of developing a skin functional food (Jung et al., 2021) .

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Glycin and aging: Evidence and mechanisms.
Adiv A Johnson et al. Ageing Res Rev. 2023 Jun.

This study shows that glycine prolongs lifespan and improves health in aging-related disease models, which in turn extends lifespan by mimicking methionine restriction and activating autophagy activation (Johnson et al., 2023).

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Increased levels of glycine tRNA associated with collagen synthesis.
P S Leboy et al. Arch Biochem Biophys. 1987 Dec.

This study shows that the increased levels of tRNAGly required for chicken Type I collagen synthesis are based on increased amounts of the major tRNAGly isoacceptor in other tissues (Leboy et al., 1987).

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