Wet working conditions increase brittleness of nails, but do not cause it.

The incidence of brittle nails is higher in women than in men. Repeatedly a suspected cause for the higher incidence of brittle nails in women is the frequent exposure to water. This study was aimed at clarifying whether wet working conditions increase the incidence of brittle nails in women and men in a similar degree. We determined the incidence of brittle nails in 511 persons in professions that involve frequent hand contact with water. The data were compared to those of a large, non-selected control group. 50% of the female probands showed the sign of brittle nails (control group: 30.4%, p less than 0.05). Only 13.5% of the male test persons of this study had brittle nails; the difference to the control group (13.2%) was not significant. It is discussed that in women the bridges between nail corneocytes are possibly weaker than in males as a constitutional characteristic. Accordingly, frequent alternating periods of hydration and drying increase the incidence of brittle nails particularly in women.