Keratin supplementation improves hair and skin in middle-aged women: Study

Writing in the journal HealthMed​, researchers from New Zealand, France and the United States noted that the gentle pulling action triggering hair loss is typically experienced by women in this age group during combing and brushing, chemical processing and peri- and or post-menopause. Nails can also be negatively affected by cosmetic and chemical agents, while skin loses elasticity and hydration as women age.

The study presented oxidized keratin as advancing keratinocyte migration, which brings about protein expression of beneficial collagen type IV, a junctional protein that is crucial in joining the epidermal and dermal layers of the skin and anchoring hair in the hair follicle. For skin health, it highlighted that keratin has shown promise in treating dermatological conditions and forms a protective barrier that prevents water loss and protects against environmental pollutants and pathogens. 

"The unique properties of the structural protein keratin provides strength, resilience and protection to skin, hair and nails," the researchers wrote. "In this article, we discuss the role of keratin in various dermatological conditions and evaluate the effect of ingestion of a novel keratin-based formulation on hair, skin and nail health."

Markers of health​

Skin, hair and nails, indicators of health and wellness, are partly comprised of keratin—fibrous proteins that provide structure to the epidermis. Tough and insoluble, keratin, which is made up of long, coiled polypeptide chains, offers strength to this structure and guards it from environmental and mechanical stressors.

“Once ingested, keratin in a digestible form is available to be broken down by digestive enzymes leading to absorption of bioavailable keratin peptides that are then have the potential to influence cell metabolism,” the researchers wrote.

Keratin production is influenced by various factors such as genetics and hormonal and nutritional status, including sulfur amino acid metabolism.

“It’s crucial to understand how to support the production and function of keratin since it plays both physical and biological roles in the body, affecting wound healing rates, stimulating protein synthesis, and building healthy skin structures," the study noted.

Study details​

Over 60 days, the randomized, double-blind, placebo-controlled study evaluated effects in 65 women with healthy skin but damaged or stressed hair, randomly assigned to either a supplement or placebo group.

Participants in the intervention group consumed KeraGEN-IV (Keraplast Manufacturing, New Zealand), consisting of 200 mg of Keragen-IV and 550 mg of microcrystalline cellulose.

Instrumental measures of skin firmness and elasticity, hydration and skin barrier function efficiency were taken along with a hair pull test, keratin quality assessments and participants’ self-assessment of nail condition over the the test period.

The hair pull test helps evaluate diffuse scalp hair loss and follicle anchoring in the scalp, the researchers explained. Gentle traction is exerted on small group of about 60 hairs in frontal, temporal and occipital areas of the scalp, and the number of extracted hairs is counted. If the number of lost hairs is greater than nine, the pull test is suggestive of temporary hair loss. 

"The investigational product’s action of inducing collagen IV expression appears to translate to measurable improvement in hair anchoring, specifically a 43.1% reduction in hair loss in women aged 45-60 with stressed or damaged hair," the researchers reported. "Improvement in the hair keratin structure is further supported by a 17.61% increase in birefringence arising from increase in the hair cortex structural integrity following evaluation using polarimetric imaging analysis."

Additionally, the Trans Epidermal Water Loss (TEWL) assessment, which evaluates the skin barrier function efficacy and indicates skin integrity, was reduced by 12.5%—supporting KeraGEN-IV’s ability to improve skin structure. Skin elasticity increased by more than 10%. There was no difference in either nail strength or overall condition between the supplement or placebo groups.

Based on these results and recent in vitro​ and in​ vivo​ cytotoxicity assays reporting no adverse effects from keratin supplementation, the researchers called for further clinical analysis of KeraGEN-IV.

Source: HealthMED​
e-ISSN 1986-8103
“Effect of keraGEN IV Keratin oral supplementation on hair, skin, and nail attributes”
Authors: Rob Kelly et al.