Hair cosmetics, styling, and processing play key roles in counseling patients with hair loss.
Hair and scalp health must be maintained for medical and aesthetic reasons. This includes regular shampooing, conditioning, and limiting unnecessary heat styling and processing.
Direct-to-consumer hair cosmetics are available to create the illusion of volume or camouflage hair loss, but their use comes with some risk.
Literature on hair cosmetics has few randomized sham-controlled trials, and most research in this area is driven by the beauty industry. Additional collaboration between clinicians and the beauty industry is needed.
Background, definitions, and history
The desire for healthy hair is evolutionary, as the cosmetic appearance of hair is a primary indicator of youth (level of evidence: 5). Hair is considered the healthiest when it lacks damage, whether self-inflicted or environmental. In 2016, the US beauty industry had an estimated revenue of 62.46 billion US dollars (level of evidence: 5). The leading worldwide cosmetic manufacturer in 2019 was L’Oreal, with worldwide headquarters located in France; the company made approximately 33.4 billion US dollars that year (level of evidence: 5). In 2018, the global haircare industry was valued at 87.9 billion US dollars. In addition to improving hair appearance in the general population, hair cosmetics, styling, and processing have a role in altering the appearance of the hair and scalp in a way that those with hair loss value. For example, patients with androgenetic alopecia (AGA) may turn to the beauty industry for products to minimize and conceal hair loss. Therefore, a firm knowledge base of hair cosmetics is essential for the assessment and treatment of these patients. In this chapter, we will review the fundamentals of healthy scalp and hair follicle maintenance, styling techniques, and hair processing options. Furthermore, we will emphasize their utility in the treatment of patients with AGA.
Indications and patient selection
Within the United States in 2021, routine hair and scalp hygiene and styling products were readily available and routinely used in the general population. However, a thorough understanding of hair cosmetics, styling, and processing requires individuals to also understand the concept of weathering. Weathering is a hair shaft process that results in hair damage from root to tip and includes decreased shine, elasticity, and, ultimately, breakage (level of evidence: 5) ( Pearl 5.1 ). , There are two types of weathering: natural and accelerated. In the process of natural weathering, the cuticle is worn away over time from hair brushing, combing, or other physical haircare maintenance techniques. Accelerated weathering includes damage to the hair’s cuticle and cortex proteins ( Fig. 5.1 ). , Those with long hair often demonstrate more severe weathering caused by repetitive injury of the hair shaft over time (level of evidence: 5). Processes that weaken hair fiber integrity and contribute to accelerated weathering include heat styling and chemical processing such as bleaching and permanent waving (level of evidence: 5). , Processes such as straightening, bleaching, and perming alter the protein structures of hair, causing irreversible damage (level of evidence: 5). , Other environmental factors in weathering include prolonged exposure to sunlight, resulting in loss of tensile strength, color changes, embrittlement, and split ends (level of evidence: 5). Sunlight exposure causes proteins and lipids to undergo degradation via a reaction between aromatic amino acid species and ultraviolet light, which produces reactive oxygen species such as hydrogen peroxide, hydroperoxides, and singlet oxygen. Overall, weathering of the hair fiber is expected over time in those with and without hair and scalp disease.
Weathering is a process that results in damage to the hair shaft and may include decreased shine, elasticity, and breakage.
In addition to the general population seeking hair cosmetics for hygiene and to managing weathering, those with hair and scalp disease may also turn to the beauty industry for solutions. Patients with excessive sweat, oil, dirt, or hair product use may find regular hair and scalp hygiene especially helpful for follicular aesthetic appearance and prevention of the development of scalp diseases such as dandruff, seborrheic dermatitis, or folliculitis. Those with hair or scalp disease such as psoriasis, atopic dermatitis, dermatomyositis, or tinea may find that perfecting a hair and scalp hygiene routine along with personalized styling is important for overall disease management. Furthermore, cosmetic products are the foundation of treatment for those with hair breakage such as trichorrhexis nodosa and trichoptilosis ( Figs. 5.2 and 5.3 ).
Those with AGA may find unique cosmetic benefits in styling and camouflaging to disguise hair thinning. In AGA, hair follicles are miniaturized, which contributes to the overall appearance of lower hair density in affected scalp regions. Additionally, it has been proposed that the disease process, which results in reduced follicular fiber diameter, allows for increased vulnerability to fracture and increased weathering of hair fibers (level of evidence: 5). , Those with early and mild androgenetic alopecia may find that the at-home beauty industry offers sufficient cosmetic and styling options. Those with more progressed AGA will likely need the help of dermatologists and professional stylists to camouflage hair loss as part of a comprehensive management plan.
Of note, patients with a history of contact dermatitis may find the hair and scalp cosmetics industry difficult to navigate given the numerous ingredients found in products. Routine patch testing or patch testing within a tertiary care center may be required to finesse product selection (level of evidence: 5). When managing patients with alopecia, physicians must recognize that hair cosmetics, processing, and styling options are unique to each patient as product choices can be affected by hair and scalp disease, hair type, and social determinants of health.
Immediate desired changes in cosmetic appearance can be achieved with topical camouflaging agents, hair dyes, conditioning, volumizers, and heat styling tools in those with early AGA. Within days to weeks of initiating regular cleansing and shampooing of the scalp, a noticeable aesthetic difference in scale and scalp erythema may be noted in those with concomitant seborrheic dermatitis (level of evidence: 2b). Over years, combining medical hair growth treatment options with hair cosmetics, styling, and processing as part of a comprehensive plan can result in an improved appearance. As the hair grows over time, scalp and hair shaft health may improve, including increased shine, length, and strength, along with decreases in hair-shaft disease (e.g., bubble hair, trichorrhexis nodosa, trichoptilosis, trichoschisis). Without addressing the AGA disease process, the disease may continue to progress, and these techniques may slowly prove to be less useful. Patients may have the expectation that, with medical treatment, their hair will grow more rapidly, and results will be immediate. However, the rate of hair growth varies among individuals and can differ from scalp location and age (level of evidence: 2b) ( Pearl 5.2 ). Adjusting patient expectations with regard to expected results and timelines is fundamental to cosmetic hair counseling success. ,
Hair growth rate varies among individuals, and the technology to change hair growth rate is lacking.
Treatment technique/best practices
Shampoo is a key component of every healthy haircare routine. Although shampoos can have a variety of secondary functions, they are first and foremost scalp and hair cleansing products. Shampoos commonly come in liquid formulations; however, dry and solid shampoos also exist (level of evidence: 2b). , The goal of shampooing is to remove sebum, dirt, scale, sweat, dust, and other environmental pollutants, thus helping prevent the onset of various scalp-related conditions such as seborrheic dermatitis or dandruff ( Pearl 5.3 ). Consistent scalp and hair hygiene with shampoo usage is a cornerstone to the regimen of patients with alopecia ( Fig. 5.4 ).
The goal of shampooing is to remove sebum, dirt, scale, sweat, dust, and other pollutants.
Although shampoo usage is fairly ubiquitous, there can sometimes be confusion surrounding how exactly it should be used. In general, the hair should be wet, then a custom amount of shampoo should be massaged on the scalp and the proximal hair shafts (see Fig. 5.4 ). The shampoo should then be fully rinsed out of the hair and scalp (level of evidence: 5). The amount of shampoo needed may vary between individuals and by scalp size and product type. Shampooing frequency is determined by numerous factors including hair type, hairstyle, sweat-producing activity level, and hairstyling product usage. Individuals with oily hair or fine hair may need to shampoo their hair more often than those with dry hair (level of evidence: 5). Those with curly or dry hair may have more fragile hair shafts susceptible to breakage with frequent shampooing; therefore, some patients may need to limit shampoo-based washing to approximately every 7 to 14 days (level of evidence: 5). , In the authors’ experience, the presence of erythema, pruritus, flakes, or scale on the scalp or proximal hair shaft may indicate that the scalp needs to be washed more often. In general, hair should not be washed more than once a day. Sometimes, patients with hair loss will shampoo their hair more often than necessary to give the appearance of more volume, as sebum can weigh down the hair. Consumers should seek shampoos labeled for their hair type. For example, those that have fine hair should look with shampoo labels for “fine hair.” Those with curly or dry hair should look for labels for “curly,” “dry,” or “very dry” hair. Those with color-treated hair or bleached hair should also look for shampoos labeled for their hair type.
In the twenty-first century, shampoo ingredients have increasingly become a topic of interest for consumers. Shampoos may contain a wide variety of ingredients: surfactants, conditioners, sequestering agents, preservatives, fragrances, specialty additives, and various other ingredients aimed at influencing the physical properties of the shampoo. In general, the most important shampoo ingredients are surfactants, as they are the ingredients responsible for cleansing the hair and scalp. Surfactants reduce surface tension and can act as detergents. They are structured as amphiphilic molecules, and remove oil from the hair and scalp by attaching to water on their hydrophilic ends and oil on their lipophilic ends (level of evidence: 5). Shampoo surfactants can be anionic, cationic, nonionic, amphoteric, or natural, and shampoos typically have more than one type of surfactant ( Table 5.1 ). Sodium laureth sulfate and amphoteric surfactants are common surfactants used in shampoos for hair loss. Sodium laureth sulfate is effective at removing sebum, and is not considered to be as harsh as sodium lauryl sulfate, another anionic surfactant. Sodium laureth sulfate and amphoteric surfactants are beneficial to patients with hair loss because they are gentle, but patients and dermatologists alike should be aware that cocamidopropyl betaine, an amphoteric surfactant, is a common allergen ( Fig. 5.5 ) (level of evidence: 5). ,
|Surfactant||Chemical Properties||Cleansing Ability||Examples|
|Anionic||Polar group is negatively charged||Deep cleansing||Sodium laureth sulfate, sodium lauryl sulfate|
|Cationic||Polar group is positively charged||Little sebum removal potential||Ammonioesters|
|Nonionic||No polar group||Mild cleansing, often used as secondary surfactant||Polyoxyethylene fatty alcohols, polyoxyethylene sorbitol esters and alkanolamides|
|Amphoteric||Two polar groups, one positively charged and one negatively charged||Act as anionic surfactants at high pHs and cationic surfactants at low pHs||Cocamidopropyl betaine, sodium lauriminodipropionate|
Shampoo components that may be beneficial for patients with hair loss are pH-adjusting acids and conditioning agents. Glycolic acid and other pH-adjusting acids are added to shampoos to neutralize the basic detergents and avoid breakage. Conditioning shampoo agents, also known as 2-in-1 shampoos, often contain glycerin or dimethicone and may help with moisturizing the follicle and improving the aesthetic appearance in a patient with alopecia. , , However, some patients may require more aggressive conditioning to avoid hair breakage.
Another category of shampoos is sulfate-free shampoos. Sulfates, particularly sodium lauryl sulfate, can be quite drying, and individuals with dry hair might not prefer them for this reason. Sulfate-free shampoos are formulated without anionic surfactants and instead contain milder surfactants (level of evidence: 2b). Despite the popularity of these shampoos, not much is known about their relative effectiveness (level of evidence: 2b).
Medicated shampoos are also available to patients with specific scalp concerns such as dandruff. Dandruff, or scalp flaking, is thought to be caused by Malassezia yeast (level of evidence: 2b). Zinc pyrithione is an antimicrobial agent commonly used in antidandruff shampoos; it functions by breaking down iron-sulfur proteins that are essential for microbe survival and improving the condition of the stratum corneum (level of evidence: 2b). Ketoconazole is another antimicrobial agent used in antidandruff shampoos (level of evidence: 2b). Draelos et al. performed a double-blind cross over study to compare the effectiveness and tolerability of 1% zinc pyrithione conditioning shampoo and 2% ketoconazole shampoo in women with dandruff. In terms of overall response, the majority of participants preferred the former. However, a different prospective study reported that 2% ketoconazole shampoo was more effective at eliminating dandruff compared with 1% zinc pyrithione shampoo (level of evidence: 2b). Selenium sulfide is another common antidandruff ingredient. In one study, it was found to be as effective as 2% ketoconazole shampoo in reducing dandruff (level of evidence: 2b).
Conditioning agents help replace some of the moisture lost from cleansing, making the hair more manageable and aesthetically pleasing. Examples of conditioning agents are dimethicone and glycerin. Conditioners are hair products that should be applied to the ends of the hair and the length of the hair shaft, avoiding the scalp. In general, the goal of conditioning is to increase the aesthetic and physical quality of the hair ( Pearl 5.4 ). Conditioners typically contain cationic detergents, polymers, emollients, and other ingredients aimed at influencing the physical properties of the conditioner. Cationic detergents are ineffective at removing sebum, but their positive charge allows them to adhere to the negatively charged hair, which neutralizes the hair and thus reduces static. Polymers can flatten the cuticle, resulting in more shine and less friction (level of evidence: 5). , Conditioners can also contain added proteins, which can temporarily increase the strength and thickness of hair. There are different types of conditioners on the market, including instant, deep, and leave-in conditioners. Instant conditioners are the most common and are typically left in the hair for 5 minutes after shampooing, and are then washed out. Deep conditioners typically have a cream consistency and are left in the hair for approximately 1 to 30 minutes. In contrast, leave-in conditioners are not meant to be washed out of the hair (level of evidence: 5). ,
Conditioners function to improve aesthetic appearance and physical quality and reduce hair breakage.
Use of conditioners can reduce hair breakage and thus reduce further hair loss. It is therefore recommended that patients with hair loss use conditioners (level of evidence: 5). Conditioners with dimethicone are recommended to patients with hair loss because they are effective at conditioning the hair while not weighing it down. , Patients with hair loss may also benefit from conditioners with added proteins because, as mentioned, they can temporarily increase the strength and thickness of the hair. Additionally, such patients may benefit from deep conditioning treatments and leave-in conditioners. Leave-in conditioners can also temporarily increase the thickness of the hair.
Hairstyling techniques for concealment
Different styling techniques and products can be used to conceal hair loss. These techniques may be used at any stage of hair loss, although some techniques may provide more satisfactory results in the earlier stages. In male AGA, thinning and recession may progress until a receding hairline, starting at the temples, meets the balding at the vertex (level of evidence: 5). In female patients, patterned hair loss may begin with a widening central part width, which may extend into an ovular, then Christmas tree like pattern, ultimately resulting in circular balding at the mid scalp (level of evidence: 5). Although the frontal hairline may be preserved, thinning at the frontal-temporal hairline is also possible in women.
In regard to hairstyles, one route for concealing hair loss is maintaining hair in its natural state and growing it longer, if possible, to increase volume and provide better natural coverage. This may reduce damage caused by tight hairstyles, artificial hairpieces, and chemical processing techniques (level of evidence: 5). , Another method to minimize the appearance of balding at the frontal anterior and mid scalp regions is the comb-over technique ( Fig. 5.6 ). For a comb-over to be successful, the individual’s hair must be grown out enough to cover the location of concern. Then, a side hair part can be created, and hair can be combed over to conceal the balding area. This method may minimize the appearance of balding at the frontal anterior and mid scalp regions. In general, it may be beneficial to choose a hairstyle that allows for more regular washing to maintain scalp health and help promote new hair growth.