A study highlighted by Larson reveals that 25% of nurses suffer from dry and damaged skin. This condition ironically undermines the very goal of their hand-washing practices, which is to limit the spread of infectious bacteria. Healthy skin plays a crucial role in maintaining hygiene, as it naturally sheds millions of particles daily, some of which contain bacteria. However, when the skin is dry and damaged, it tends to flake off more easily, propelling bacteria into the environment.

Larson emphasizes that compromised skin not only sheds more but also holds a greater number of pathogens than healthy skin. This paradox indicates that the relentless hand-washing, meant to prevent infection, could inadvertently contribute to a greater risk of bacterial spread among health care professionals. The implications of this finding raise important questions about maintaining skin health while ensuring hygiene in medical settings, as noted in Mary Roach's book, "Packing for Mars: The Curious Science of Life in the Void."