When people think about healthy hair and nails, they often focus on what they can see: shine, thickness, smoothness, or length. But the foundation of healthy hair and nails begins at a much deeper level—with the proteins that provide structure and resilience. One of the most important structural proteins involved in hair and nail health is keratin.
What is Keratin?
Keratin is a strong, fibrous protein that forms the primary structural component of hair and nails. It provides strength, durability, and protection, helping these tissues withstand everyday stress. Within the hair shaft, keratin forms a protective framework, helping hair maintain its integrity and resilience. Keratin also helps provide the hardness and durability we associate with healthy nails. Because hair and nails are rapidly renewing tissues, they require a consistent supply of nutrients and building blocks to support their normal structure and function.
Hair and nail health naturally change throughout life. Throughout adulthood, many people start to notice changes such as increased dryness or brittleness, reduced shine or elasticity, increased breakage or changes in thickness and texture. Similarly, many people notice their nails become weaker, thinner, or more prone to splitting and peeling.
These changes can be influenced by many factors, including age, hormonal shifts, oxidative stress, nutritional gaps, physical stress, and repeated exposure to chemical treatments, heat styling, water and other environmental stressors. As these factors accumulate, the integrity of these structures may become compromised.
While topical hair and nail care products may temporarily improve the appearance and manageability of hair and nails, they primarily work only on the surface. Nutritional keratin supplements take a different approach by providing the body with building blocks needed to help maintain healthy hair and nails from within.
Why Does the Form of Keratin Matter?
When keratin is consumed, it is broken down and digested into usable components—smaller peptides and amino acids, including cysteine. Cysteine is particularly important because it helps form the disulfide bonds that give hair and nails much of their strength. These peptides and amino acids are then absorbed and used throughout the body as building blocks for proteins. Some can ultimately be used in the production of new keratin within the hair follicle and nail matrix.
However, not all keratin supplements provide the same level of research and bioavailability. Because keratin is naturally a large, complex protein, it is difficult for the body to digest and utilize. Specially processed keratin like keraGEN-IV® provide a more bioavailable form of keratin peptides, with health benefits backed by clinical research.
In one randomized, placebo-controlled clinical study, participants taking keraGEN-IV experienced a significant improvement in hair anchoring as measured by a standardized hair-pull test. The study reported a 43% reduction in hair loss. In addition to its high cysteine content, this effect may be related to keraGEN-IV’s potential to promote the expression of collagen IV and VII—structural proteins that help support the skin and tissues surrounding the hair follicle.
Keratin Is One Piece of the Bigger Picture
While keratin is a foundational component of hair and nails, their health depends on more than one nutrient. Biotin, zinc and vitamin A also play important roles in various processes involved in hair and nail health, such as cellular processes and tissue maintenance.
Lifestyle and genetics matter, too. Adequate nutrition, hormonal balance and stress management all contribute to maintaining hair and nail quality. That’s why supporting healthy hair and nails is best approached from the inside out—with a foundation of good nutrition and healthy lifestyle habits, complemented by targeted nutritional support.
As with any dietary supplement, it’s important to consult with a healthcare professional before adding a keratin supplement to your routine.
References
Kelly, R., et al. Effect of keraGEN IV Keratin oral supplementation on hair, skin, and nail attributes. HealthMED. 2024, 18 (2), 35-45.
Tang, L., et al. Wool-derived keratin stimulates human keratinocyte migration and types IV and VII collagen expression. Exp Dermatol. 2021, 21(6), 458-460.