As an Experiment Man Goes without Soap or Shampoo for a Year...
Sean Bonner reasoned that human beings have evolved without soap, and therefore it's unnatural to strip away the dirt, oil, and grime of daily life with it. As an experiment, he stopped using soap and shampoo for a year...
https://www.neatorama.com/2011/01/07/as-an-experiment-man-goes-without-soap-or-shampoo-for-a-year/
