Supplement
Silk amino acids are the building blocks of silk protein, including sericin from silkworm cocoons, and they supply amino acids like serine that the body uses to build its own proteins. People mostly look at them for skin hydration, and lab studies found sericin binds water and holds moisture well, though the evidence is very limited. Nearly all of this came from cell and animal work or cosmetic research, with no human trials of oral supplements, so what it does when swallowed remains unknown.
Sources: PMID 27965981; PMID 33918380
- Updated
- How we grade
- 8 studies cited
- Best evidence
- Grade D
- Conditions studied
- 1
- Outcomes
- 5
- Graded outcomes
- 0005
Evidence by condition
- Strong
- Moderate
- Limited
- Very limited
General
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Skin Hydration In vitro studies demonstrate sericin's strong water-binding and moisturizing properties due to high serine content. Animal studies and cosmetic research support topical skin hydration effects, but no human clinical trials have evaluated oral supplementation for skin hydration outcomes. | Improves (the measure goes up) | Small effect | 4 studies | |||
Studies that measured skin hydration
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| Collagen Production An in vitro study found that sericin from different silk strains stimulated collagen production and nitric oxide release in cell culture models. Results varied by amino acid composition of the sericin extract, suggesting strain-dependent bioactivity. | Improves (the measure goes up) | Small effect | 2 studies | |||
| GI Protection Animal studies suggest that non-hydrolyzed sericin (Sericin-L) may have gastrointestinal protective effects, potentially acting as a gut-lining protectant. This form is not absorbed systemically but may exert local effects in the GI tract. No human data available. | Improves (the measure goes up) | Small effect | 2 studies | |||
| Blood Glucose Preliminary animal studies have reported anti-diabetic effects of silk sericin, though evidence is very limited and mechanisms are not well-characterized. No human trials have investigated oral sericin supplementation for glycemic outcomes. | Improves (the measure goes down) | Small effect | 2 studies | |||
| Grade | Outcome | Effect | Size | Studies | People | Studies list |
|---|---|---|---|---|---|---|
| Antioxidant Status Multiple in vitro studies and chemical characterization analyses confirm sericin possesses antioxidant activity, including free radical scavenging capacity. A 2025 study of Portuguese silkworm cocoon sericin confirmed bioactive antioxidant properties, though no human trials have been conducted. | Improves (the measure goes up) | Small effect | 4 studies | |||
Studies that measured antioxidant status
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Key findings
- Skin HydrationImproves (the measure goes up)
- Antioxidant StatusImproves (the measure goes up)
- Collagen ProductionImproves (the measure goes up)
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- Grade D
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Studies cited
8 studies from PubMed
- Chemical Characterization and Bioactivities of Sericin Extracted from Silkworm Cocoons from Two Regions of Portugal.
- Silk Sericin Protein Materials: Characteristics and Applications in Food-Sector Industries.
- A comprehensive review of recent advances in silk sericin: Extraction approaches, structure, biochemical characterization, and biomedical applications.
- Changes in Amino Acid Profiles and Bioactive Compounds of Thai Silk Cocoons as Affected by Water Extraction.
- Silkworm Sericin: Properties and Biomedical Applications.
- The effects of Bombyx mori silk strain and extraction time on the molecular and biological characteristics of sericin.
- Isolation and bioactivities of a non-sericin component from cocoon shell silk sericin of the silkworm Bombyx mori.
- The effect of sericin with variable amino-acid content from different silk strains on the production of collagen and nitric oxide.