The changes of hair growth with aging / 中华皮肤科杂志

ABSTRACT

Objective To investigate the changes of hair growth with the increase of age and to develop a new practical method to evaluate the extent of aging. Methods After the approval of the ethnic committee, 96 healthy volunteers (44 males, 52 females, aged 30 ~ 78 years) were recruited into the study and divided into 4 groups based on the age 30-group, 40-group, 50-group and 60-group. Macrophotographs were taken from the vertex. Hair density and percentages of black hairs were counted using Photoshop7.0 software. Ten hairs were randomly plucked from the specified scalp area,and the diameters of hair shaft and hair bulb were examined by a micrometer. The percentages of the follicles, based on their morphology, at different phases of the hair cycle, were counted. Results With the increase of age, the hair density, diameters of hair shaft as well as hair bulb, the percentages of anagen follicles and grey hairs all decreased, while the percentages of telogen follicles and white hairs increased, and significant difference was found between the 60-group and other 3 groups. In each group, the difference between males and females was found only in some parameters. The diameter of hair bulb positively correlated with that of hair shaft. Conclusion This study suggests that the parameters of hair growth could be used to help rating the extent of aging.