The Effects of Aging on Hair–More Than Just Amount 468 Table 6. Hair ellipticity by age for two groups of Caucasians19, 20 French Canadians American Caucasians Age Group Ellipticity Ellipticity 0 to 9 1.36 1.34 10 to 19 1.37 1.36 20 to 29 1.39 1.32 30 to 49 1.38 1.34 50 to 89 1.40 1.33 0 to 89 1.38 300 = N 1.34 340 = N The solid line indicates that those ellipticities are not significantly different for those groups. The data from these two studies were analyzed by ANOVA and by the matched pairs test. Both statistical tests show that ellipticity is different between French Canadians and American Caucasians, but there is no significant difference between ellipticity of the different age groups. Even if there were differences among the age groups, the difference would be relatively small, since both groups varied by less than ± 2% among age groups for each group of Caucasians. Another study on ellipticity versus age over a similar age range is shown in the aforementioned study by Nagase et al. on Japanese hair taken from the “top of the head.”18 This paper described ellipticity in terms of the ratio of maximum to minimum diameters among 132 Japanese females, ages 10 to 70. The authors found no statistically significant effect of ellipticity with age over this age range. The average ellipticity was 1.28 and the r2 = 0.0001 showing that the variation in ellipticity by age among Japanese women was neither meaningful nor significant. This study suggests there is no effect of age on hair fiber ellipticity for Japanese females between the ages of 10 and 70. Another paper by Nagase et al.26 reported ellipticity determinations on what can be presumed to be the same study data: 132 Japanese females, ages 10 to 70. Although the average ellipticity over the total group was 1.28 ± 0.15, the total variation among the 8,926 individual hair fibers was 1.02–2.19, testifying to the necessity for measuring a large number of hairs to obtain meaningful data for ellipticity for individuals or for groups of subjects.