Quick Summary

Keratin, particularly in its hydrolyzed form, is a protein supplement classified under Joint, Skin & Beauty supplements. It is derived from a fibrous structural protein found naturally in hair, skin, and nails. Hydrolyzed keratin has been studied for its potential effects on hair, skin, nails, and joint health; however, current scientific evidence from human clinical trials is limited or insufficient to draw firm conclusions. Official dosage guidelines and authorized European Union (EU) health claims are not available for keratin supplementation at this time.

What Is It?

Keratin is a fibrous structural protein that forms a key component of epithelial tissues, including the outer layer of skin, hair, and nails. Hydrolyzed keratin refers to keratin that has undergone enzymatic or chemical processing to break it down into smaller peptides and amino acids, which are thought to improve its suitability for oral supplementation by enhancing digestibility.

How It May Work in the Body

Keratin supplementation is theorized to support the structural integrity of keratin-containing tissues—such as skin, hair, and nails—and possibly joint components due to its protein content. Proposed mechanisms include:

  • Providing amino acids and peptides that may serve as building blocks for synthesis and repair of keratin-rich tissues.
  • Potentially supporting joint and cartilage health through additional protein resources.

However, these mechanisms remain theoretical as there is currently insufficient human clinical evidence to confirm these effects or determine their clinical relevance.

Common Supplement Forms

Keratin supplements are typically available in the following forms:

  • Hydrolyzed keratin peptides, designed for improved absorption
  • Keratin protein powders
  • Capsules or tablets containing keratin peptides

Typical Dosage and How It Is Used

There are no officially established recommended daily intakes or standardized dosages for hydrolyzed keratin supplementation. Due to the absence of authoritative guidelines, consumers are advised to follow manufacturer instructions and consult healthcare providers when considering use. Safety data remains limited, so cautious use is warranted.

Natural Sources

Keratin is naturally found in human hair, skin, and nails. It is also abundant in various animal-derived materials such as horns, hooves, feathers, and wool.

Absorption and Bioavailability

Hydrolyzed keratin is formulated to improve digestibility and absorption by breaking the intact keratin protein into smaller peptides. This hydrolyzed form is expected to be more bioavailable than native keratin protein. However, detailed comparative data on absorption differences among keratin supplement forms is not well-established.

Potential Benefits: What Does the Evidence Say?

Skin, Hair, Nails, and Joint Health:

Research on keratin supplementation’s impact on skin, hair, nails, or joint health is currently insufficient. There is a lack of conclusive human clinical trial data to support benefit claims. Most available information is theoretical or comes from preclinical studies, without relevant randomized controlled trials or systematic reviews demonstrating efficacy.

Side Effects and Safety

The supplied evidence does not report common side effects, toxicity, or adverse events related to keratin supplementation. Nevertheless, supplement quality concerns exist due to potential variability in purity and regulation. No formal contraindications have been identified based on current data.

Drug and Supplement Interactions

There is no documented evidence of interactions between keratin supplements and medications or other dietary supplements.

Who Should Be Careful?

Due to limited safety data, individuals who are pregnant, breastfeeding, have existing medical conditions, are on medications, or are planning surgery should exercise caution and consult a healthcare professional before using keratin supplements.

Pregnancy, Breastfeeding and Special Populations

The safety of keratin supplementation during pregnancy and breastfeeding has not been established. Use in these populations should only be considered under medical advice. Evidence regarding use in children or other special populations is currently lacking.

Quality, Standardization and What to Look For

Keratin supplements may vary in quality due to the lack of standardized manufacturing controls. When choosing a keratin supplement, it is advisable to look for products that have:

  • Third-party testing or certification to verify purity and content
  • Clear labeling of hydrolyzed keratin content
  • Good manufacturing practice (GMP) compliance

Consulting a healthcare professional before starting supplementation can help ensure safety and appropriateness.

Frequently Asked Questions

  • Is keratin supplementation effective for improving hair or nail health?

    Currently, there is insufficient scientific evidence from human studies to confirm that keratin supplements improve hair or nail health.

  • Are there any risks of taking keratin supplements?

    No significant risks have been reported in the existing evidence, but safety data remains limited, and supplement quality may vary.

  • How is hydrolyzed keratin different from regular keratin?

    Hydrolyzed keratin is broken down into smaller peptides to enhance digestibility and absorption compared with intact keratin protein.

  • Can keratin supplements replace protein in the diet?

    Keratin supplements are not a substitute for dietary protein intake. They are intended to provide specific amino acids and peptides hypothetically supporting keratin-rich tissues.

  • Are there any EU-authorized health claims for keratin supplements?

    No EU-authorized health claims for keratin supplementation are currently available.

Evidence Limitations

  • No human clinical trial data on keratin supplementation efficacy or safety are currently available.
  • There is no official recommended dietary intake for keratin, limiting dosage guidance.
  • No effects have been documented or endorsed by authoritative regulatory agencies.

References

  • No published references supplied for keratin supplementation at this time.

Last Reviewed

June 2024

Disclaimer: This page is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any new supplement, especially if you are pregnant, breastfeeding, have a medical condition, or are taking medication.