The presence of body hair influences the measurement of skin hydration with the Corneometer.

Techniques for the assessment of skin hydration are often based on the electrical properties of the stratum corneum. A commonly used instrument for measurements of skin moisture is the corneometer, which detects changes in the dielectric constant of the material in contact with the probe. It has been suggested that different materials, for example cream residues and desquamating scales, may interfere with the Corneometer readings, but this question has not been settled conclusively in previous studies. In the present study the influence of body hair was examined. Significantly lower Corneometer values were obtained on the dorsal aspect of the forearm than on the volar aspect (p < 0.05), indicating that the former region was less hydrated than the latter. After shaving of the skin, however, there was no difference in the Corneometer readings between the two regions. Thus, the presence of hair needs to be considered when the hydration status of the skin is examined with the use of a Corneometer.