Clinical and epidemiological characteristics and associated factors of hair graying: a population-based, cross-sectional study in Turkey

Abstract Background Hair graying is common in humans; but there is scarce data about its epidemiology. Objective This study aimed to evaluate the clinical and epidemiological characteristics and associated factors of hair graying. Methods A total of 1541 volunteers between 15 and 65 years old were included in this population-based, cross-sectional study. A questionnaire on characteristics and associated factors of hair graying was filled in by face-to-face interview method. Results One thousand sixty three participants (69.0%) had hair graying. The mean onset age of hair graying was 32.9 ± 9.8 years. It was 31.7 ± 9.5 years in females, whereas 33.7 ± 10.0 years in males (p = 0.001). The most common involved area of hair graying at the onset and at the time of the interview was temporal region. When it was evaluated by gender, it was temporal in males whereas parietal in females. Hair graying was more severe in males than in females and in late-onset hair graying than early-onset hair graying (respectively, p = 0.000, p < 0.001). The most common involved area at the onset and at the present was temporal in severe hair graying; whereas parietal in mild hair graying. In logistic regression analysis, age, educational status, presence of hair loss, skin type, family history of early-onset hair graying and anxiety were independently related to hair graying (p < 0.05). Study limitations The study was performed in only Turkish individuals. The recall biases were another limitations. Conclusion Male gender, late-onset and temporal-onset of hair graying may be considered to be poor prognostic factors for hair graying. There is need for further epidemiological studies in people with different ethnic origin to illuminate the clinical and epidemiological characteristics and associated factors of hair graying.

Influence of different cosmetic vehicles in mechanical and physical properties of hair treated with oxidative hair dyes

ABSTRACT Hair care products play a significant role in the cosmetic market and aim at improving hair brightness, breakage resistance, and color change. In this study, we analyzed the possibility of the formulation of oxidative dyes in different vehicles impacting the hair's both mechanical and physical properties. Light brown and light blond dyes were prepared using eight different vehicles. Among these, four vehicles were emulsifying agents and four gelling agents. Each formulation was applied to two types of virgin Caucasian hair (light blond and dark brown). Physical, chemical, and organoleptic properties of each formulation were assessed, as well as changes in hair parameters after oxidative dyeing, such as staining intensity, brightness, and breaking strength. The parameters of color and brightness differed in some formulations, but the hair type also responded differently. Brightness parameter was increased in dark brown hair colored with both dyes, whereas light blond hair showed the opposite result. Regarding the breaking strength, there were no significant differences between the two kinds of tresses. Cosmetic formulations should adjust the consumer desired effects (e.g. color change) in order to present minimal drawbacks (e.g. decrease of hair brightness and strength). Thus, the study of different vehicles is important when establishing the best oxidative dye formulation.

An Innovative Scalp-Dyeing Technique with Gentian Violet Solution During Follicular Unit Extraction for White-Haired Follicular Units

There exist some restrictions and difficulties in performing follicular unit extraction (FUE) in white-haired patients, for several reasons. In this paper, we introduce a novel technique for visualizing white hair during the punching procedure and graft preparation in FUE for white-haired patients. In white-haired older male patients, we dyed the surrounding scalp skin purple with a gentian violet solution-stained toothpick. Our method has several advantages: surgeons can easily focus on the center of the follicular unit and rapidly perform punching, they can recognize the condition of the harvested follicular units during FUE, and the hair transplant team can secure a clear view for trimming and loading into the implanter. We suggest that scalp dyeing in difficult FUE procedures, especially in patients with white hair, may be a simple method that provides a good visualization for donor site harvesting and for microdissection.

The Pattern of Hair Dyeing in Koreans with Gray Hair

BACKGROUND: Hair graying is considered as a part of normal ageing process. Nonetheless, this process raises a significant cosmetic concern, especially among ethnic Korean elderly whose baseline hair color is black. For this reason, Korean elderly dye their hair with frequency despite the risk of dermatologic problems such as allergic contact dermatitis. OBJECTIVE: In this study, the authors investigate the prevalence and pattern of hair dyeing and its relation with scalp diseases in Korea. METHODS: Six hundred twenty subjects (330 men and 290 women) with graying hair were given a questionnaire survery and underwent a physical examination. RESULTS: Of the 620 total, 272 subjects (43.9%) dyed their hair. Hair dyeing was significantly more frequent among women than among men (p<0.001). Subjects from 50 to 69 years of age showed higher prevalence of hair dyeing when compared to either younger or older groups. Subjective self-assessment of the extent of hair graying was associated with increased prevalence of hair dyeing, that is, individuals who feel graying has advanced by more than 20% of the overall hair were much more likely to dye their hair (p<0.001). Hair dyeing did not correlate with either alopecia or scalp disease. CONCLUSION: Our survey has found that the prevalence of hair dyeing is higher among Korean women than men. People in their fifties and sixties and people with more than 20% extent of grayness were more likely to dye their hair than otherwise. Hair dyeing was not associated with any increase in the prevalence of scalp diseases.

Allelic Frequencies of 20 Visible Phenotype Variants in the Korean Population

The prediction of externally visible characteristics from DNA has been studied for forensic genetics over the last few years. Externally visible characteristics include hair, skin, and eye color, height, and facial morphology, which have high heritability. Recent studies using genome-wide association analysis have identified genes and variations that correlate with human visible phenotypes and developed phenotype prediction programs. However, most prediction models were constructed and validated based on genotype and phenotype information on Europeans. Therefore, we need to validate prediction models in diverse ethnic populations. In this study, we selected potentially useful variations for forensic science that are associated with hair and eye color, iris pattern, and facial morphology, based on previous studies, and analyzed their frequencies in 1,920 Koreans. Among 20 single nucleotide polymorphisms (SNPs), 10 SNPs were polymorphic, 6 SNPs were very rare (minor allele frequency < 0.005), and 4 SNPs were monomorphic in the Korean population. Even though the usability of these SNPs should be verified by an association study in Koreans, this study provides 10 potential SNP markers for forensic science for externally visible characteristics in the Korean population.

A high resolution genetic mapping of the faded (fe) gene to a region between D10mit156 and D10mit193 on mouse chromosome 10 / 한국실험동물학회지

The C57BL/6J-fe/fe mouse is a coat color mutant. The coat color of the homozygote mouse becomes progressively lighter with advancing age. The faded gene (fe) of C57BL/6J-fe/fe was mapped in a 2.0 cM distal to D10mit191 by our group. To make a high-resolution map, we used the Korean wild mouse (KWHM) for a backcross panel, which was captured in 1995 and has been maintained as an inbred line by our laboratory. In the inter-specific backcross panel (N=400), the fe gene was mapped to 1.0 cM distal to D10mit156. The gene order was defined: centromere -D10mit3/85 (1.3+/-0.6 cM)-D10mit155 (1.3+/-0.6 cM)-D10mit191 (2.0+/-0.7 cM)-D10mit156 (1.0+/-0.5 cM)-fe-D10mit193 (1.3+/-0.6 cM)-D10mit54 (1.0+/-0.5 cM)-D10mit44 (8.5+/-1.4 cM)-D10mit42 (10.0+/-1.5 cM). The measured distance between D10mit191 and D10mit 44 differed in both inter-specific (DBA/2) and intra-specific (KWHM) backcross panels (14.2 vs 13.8 cM). Taken together, our high-resolution linkage map of the fe locus from an intra-specific backcross panel will provide a good entry point to isolate the fe gene.