Chapter 14 483 changes at middle- to advanced age are more noticeably significant for women than for men, due to menopause. Wills et al.56 in their study on pre- and post-menopausal effects have shown that these hair changes affect hair greasiness, hair shine, hair softness, and smoothness. All four of these properties are decreased significantly by menopause and age, and these effects are most likely also seen at puberty but in a reverse direction. The effects of hair greasiness on combing ease and hair luster have been described above. Its effects on hair handle or feel as it relates to hair friction will be described in the next section. Aging of hair and its impact on hair handle or feel: Wortmann and Schwan-Jonczyk61 conducted a study on four types of European hair braids and found that the bending properties of single fibers and fiber friction were the most relevant properties related to handle or feel. Diameter, ellipticity, bending stiffness, and friction were all found to be significantly different among the hair braids. Single fiber friction was determined by a capstan method on root, middle, and tip sections of hairs. Handle or feel was perceived as inferior when the hair was evaluated by panelists as coarse and the bending stiffness was high. Friction was also important to hair feel, especially in the tip regions of the hair. Hair perceived as fine was soft, and friction appeared to play less of a role than in hair perceived as coarse. Since the bending properties of hair increase with fiber diameter, which increases for females through their late 30s and for males through their late teens, this parameter alone will provide a coarse contribution to hair feel until diameter peaks. However, to a large segment of the Caucasian and Asian populations, especially those of advancing age, to increase hair fiber diameter would increase hair body and style retention and be perceived as very beneficial. Other factors such as greasiness, which increases dramatically at puberty and then decreases slowly until menopause, when it decreases more rapidly, affects friction and fiber cohesion which will also play a role in the perception of hair as fine or coarse with age. So, the overall effects of these combined