Colorimetry Provides a Rapid Objective Measurement of De Novo Hair Growth Rate in Mice

The study demonstrated that tristimulus colorimetry, specifically the L* value, provided a sensitive and quantitative measure of de novo hair growth in depilated mice. The method was tested on agouti, albino, and black mice, and it was found that L* values changed significantly during the anagen phase. LED irradiation at 890 nm promoted hair regrowth, while 650 nm had an inhibitory effect. The hair growth rates measured by colorimetry were consistent with those observed through global assessment, suggesting that colorimetry could be a reliable tool for projecting hair growth rates in mice.