Age

20s

30s

40s

50s

60s

Hair

Hair density (N/cm²)

159.6 ± 35.9

152.7 ± 31.0**^,†

146.4 ± 30.6***

141.1 ± 30.4***^,†

130.7 ± 38.4***^,††

Hair diameter (µm)

82.5 ± 17.9

86.8 ± 15.1***

89.0 ± 12.8***

85.8 ± 10.1***^,†††

83.7 ± 16.0^†

Hair L value (AU)

17.4 ± 4.2

18.1 ± 4.5*^,†††

20.5 ± 4.7***

23.3 ± 7.2***^,†††

29.4 ± 12.3***^,†††

Gray hair ratio (grade 1 - 5)

1.21 ± 0.7

1.40 ± 0.9**^,†††

1.80 ± 0.7***

2.34 ± 0.9***^,†††

3.20 ± 1.1***^,†††

Hair color fadedness (grade 1 - 5)

1.22 ± 0.4

1.31 ± 0.5*^,†††

1.55 ± 0.6***

1.91 ± 0.7***^,†††

2.41 ± 0.9***^,†††

Scalp

Scalp water contents (µS(micro Siemens))

49.3 ± 18.7

47.2 ± 19.5^††

41.8 ± 16.9***

49.1 ± 20.7^†††

54.5 ± 20.5^†††

Transepidermal water loss (g/m²h)

21.3 ± 6.4

22.0 ± 5.4

22.1 ± 7.2

20.3 ± 6.7*^,††

17.8 ± 6.2***^,†††

Scalp sebum secretion (µg/cm²)

69.1 ± 36.8

66.3 ± 36.4^††

53.9 ± 29.4***

51.2 ± 30.5***

39.7 ± 23.5***^,††

Dandruff (grade 1 - 5)

2.57 ± 0.9

2.64 ± 0.9^†††

2.26 ± 0.8***

2.08 ± 0.8***^,††

2.09 ± 0.9***

Scalp erythema (grade 1 - 5)

1.43 ± 0.7

1.48 ± 0.8^†††

2.08 ± 0.9***

2.33 ± 0.9***^,†††

2.38 ± 0.9***^,†