These days, having beautiful hair has a multitude of meanings for consumers. While the concept is influenced by factors such as ethnicity, regional concerns and trends, gorgeous locks are always synonymous with strong, healthy looking hair.
New hair care product launches are becoming more sophisticated and reflect many of the desires traditionally reserved for skin care. One example is hair care products with anti-aging benefits. These products typically address concerns of an ageing population, which include loss of volume, enhanced breakage, roughness, dryness and poor flexibility of the hair. These needs are also applicable to younger generations.
Unlike the skin, hair is incapable of self-repair. If left untreated, it begins to look and feel unhealthy as damage accumulates.
A look at the structure
Hair is composed predominantly of protein (approximately 90 percent keratin). It also contains water, lipids, pigments and trace elements. Keratin is comprised of 18 different amino acids and forms different shapes (or conformations) depending on its location within the fibre. The three primary layers of hair fibres consist of the cuticle, cortex and medulla. The cuticle is the outer, protective layer. It consists mostly of beta (β)-keratin, which is organised into flat sheets referred to as scales. This form of keratin contains cysteine and other amino acids such as arginine, cysteic acid, isoleucine, leucine, methionine, phenylalanine, proline, threonine and tyrosine. The cortex lies under the cuticle and constitutes approximately 80 percent of hair’s mass and is responsible for its strength, elasticity and flexibility. In the cortex, polypeptides are coiled into a helical structure referred to as alpha (α)-keratin. This shape provides resiliency and allows for recoil after the fibre is stretched. In the cortex, three alpha helices are bundled together to form microfibrils. These are grouped together and embedded in a matrix of hardened, high sulphur protein. Pigment (melanin) is also embedded in the cortex. The last primary layer, the medulla, consists of an open space within the centre of the hair. This is often discontinuous and sometimes completely absent of fibres.
Most symptoms associated with damage are localised to the cuticle and cortex, which is why they are key areas of concern.
Caring for the cuticle and cortex
Normal grooming such as brushing hair can damage the cuticle by lifting and breaking individual scales, making it difficult to comb and style. Damage to the cuticle also reduces shine. Heat is destructive; blow dryers and hot irons cause the inside of the hair fibre to expand quickly, which can crack the hardened cuticle. Chemical treatments and UV exposure further compromise to the cuticle’s integrity and increase porosity. This leaves hair more susceptible to frizzing or becoming excessively dry and brittle. A compromised cuticle also allows chemicals to penetrate fibres easily and weaken the inner cortex.
A vegetable-based alternative to hydrolysed keratin has recently been identified. It consists of a cohesive solution of wheat and soy amino acids with the addition of pure arginine, serine and threonine derived from fermented vegetable sources. Fision KeraVeg 18 mimics the functional ratios of amino acids in human hair. Arginine reinforces hair fibres to resist breakage while serine acts as a precursor to ceramides and aids in providing intense conditioning properties for hair. Threonine is an essential amino acid, which supports maintenance of protein balance in the body.
Efficacy testing on chemically damaged African and Caucasian hair shows that Fision KeraVeg18 addresses the needs of both the cuticle and cortex. For all studies, performance comparisons were made between the plant-based material and hydrolysed keratin. Both ingredients were tested at two percent, either in aqueous solutions (elasticity and strength of Caucasian hair) or in a shampoo and conditioner (for the remaining studies). African hair was chemically damaged with a no-lye relaxer (Soft Sheen Carson Healthy Gloss 5 kit), while Caucasian hair was triple bleached (both chemical processes simulate real-life damage). Tests measured improvements in elasticity, strength, wet and dry combability, antioxidant capacity and a sensory evaluation.
Tests with promising results
Elasticity and strength
These characteristics are two of the defining qualities of healthy hair. Elasticity is an important attribute of healthy hair and described as hair’s ability to be stretched without damage. As a result, the more elastic the hair, the less prone it is to styling damage. The stronger the hair, the better it can withstand frequent combing forces without breaking.
In these studies, a Dia-Stron MTT175 Miniature Tensile Tester with Dia-Stron Crimp Assembly System was used to test hair’s elasticity and strength. The instrument measures elasticity as an elastic extension, which is the amount of force that can be applied to stretch the fibre before it becomes damaged. Strength is measured as total work, which is the amount of force required to break the fibre.
Fision KeraVeg18 increased the elasticity of African and Caucasian hair fibres by 16 and 18 percent respectively, proving better results than hydrolysed keratin (see Figure 1 and 2). It was also shown to increase the strength of African hair by 3.9 percent and Caucasian hair by 21 percent (see Figure 1 and 2). In addition to leaving hair stronger and more resilient, these results also suggest the botanical alternative may help repair damage caused by chemical processing.
Wet and dry combing
When hair is wet or heated, hydrogen and salt bonds break and reform after the hair dries and returns to normal temperature. Both bonds contribute to hair’s elasticity and strength, which means hair is weaker and more susceptible to breakage when wet. Extra care needs to be taken when combing wet hair as the process can be highly damaging.
When dry, damaged hair is typically more difficult to style and comb. Poor manageability often results in the need to use excessive combing force, which can further damage and break individual hair fibres.
For this study, the Dia-Stron MTT175 Miniature Tensile Tester was adjusted to the combing orientation and used to measure the force required to comb wet and dry hair. Combing forces were measured after one and five applications of either test material. Fision KeraVeg18 was shown to improve wet combing by nine and 43 percent respectively, after one and five applications compared to the placebo shampoo and conditioner. The hydrolysed keratin was shown to improve wet combing by 15 and 43 percent respectively, after one and five applications. Compared to the placebo, dry combing was improved by 59 and 67 percent with the vegetable ingredient, after one and five applications, while 38 and 53 percent improvements were achieved respectively with hydrolysed keratin.
This data indicates the plant material effectively improves manageability in wet and dry hair by making hair easier to comb. In addition to improving the overall styling experience, the ingredient may help limit further damage. The study results also confirm the material is a good alternative to hydrolysed animal keratin by delivering equal combing benefits to wet hair and superior combing benefits to dry hair. Improvements in combability are an indication of a smoother, healthier cuticle.
Five women of various descents were asked to evaluate the performance of Fision KeraVeg18 versus hydrolysed keratin in a half head study on mannequins with Caucasian hair. Both materials were added separately to a commercial shampoo and conditioner at two percent. The panelists were asked to evaluate specific characteristics of wet and dry hair after one and four applications. The evaluations were determined on an 11-point scale from zero (worst) to 10 (best).
In the wet hair evaluation, panelists favoured the Fision KeraVeg18 for its ability to improve hair flexibility and allow for easier knot removal. For dry hair, panelists rated the Fision KeraVeg 18 as delivering equal performance benefits to hydrolysed keratin for knot removal, styling ease, shine and improvements in frizz and static. In addition to leaving hair looking and feeling healthier, these results demonstrate the multiple benefits Fision KeraVeg18 can deliver to fortify and rejuvenate hair.
Hair is continuously exposed to various forms of oxidative damage including Reactive Oxygen Species (ROS), which are free radicals that can damage the hair and scalp. ROS are generated by UV and heat treatments and can accelerate hair’s ageing, weaken its fibres and irritate the scalp. Hair is extremely sensitive to oxidation when wet, and as a result can be damaged easier.
Plant and animal derived protein hydrolysates, peptides and amino acids are understood to show significant antioxidant ability. The antioxidant capacities of Fision KeraVeg18 and hydrolysed keratin were measured with the Oxygen Radical Absorbance Capacity method and expressed in Trolox equivalent units. Trolox is a water-soluble analog of Vitamin E. Results indicate that Fision KeraVeg18 has an antioxidant capacity equivalent to 152μM of trolox while hydrolysed keratin is equivalent to 157μM. This data indicates Fision KeraVeg18 provides similar antioxidant protection as hydrolysed keratin to help limit oxidative damage to the hair and scalp.