Effect of Scalp Position on Tensile Properties of Single Hair Fibers

In 2018, a study involving 15 participants (9 males and 6 females) was conducted to examine the tensile properties of hair from four different scalp positions. The study found no significant differences in tensile properties between the different scalp positions, and age and gender did not significantly influence these properties. The diameter of the hair varied between scalp positions, with the lowest average diameter at position P4 (76 μm) and the highest at positions P1 and P2 (81 μm). However, this variation in diameter did not significantly affect the tensile properties of the hair. The study concluded that the lack of significant differences could be due to micro and nanoscale structural heterogeneities in the hair shaft.