You do it several times a day: You grab some soap, rub your hands together for 20 seconds or so, then rinse. Yet if you're aiming to get rid of as much bacteria as possible, you've been washing your hands all wrong. After observing the hand-washing techniques of doctors and nurses, scientists at Glasgow Caledonian University in Scotland say the WHO's six-step hand-washing technique is most effective, reducing bacteria by 21%, compared to just 6% with the three-step method backed by the CDC, per ATTN and CBS News. Lathering your hands with soap is actually just the first step. The six-step technique also involves rubbing the backs of hands, the backs of fingers, between fingers, then rotational rubbing of your thumbs, then fingers in your opposite palm, reports the Telegraph.
To determine which technique was best, scientists watched 42 doctors and 78 nurses wash their hands with an alcohol-based rub. Those who used the three-step technique saw the average bacterial count on their hands fall from 3.08 colony-forming units per milliliter to 2.88, compared to 3.28 to 2.58 CFU/mL for those who used the six-step method. However, the six-step method took 25% longer to complete for an average of 42.5 seconds. That might explain why "only 65% of providers completed the entire hand hygiene process despite participants having instructions on the technique in front of them and having their technique observed," a researcher explains in a release. She adds the study "provides a foundation for effective best practices to implement on the frontlines of healthcare." (One guy suggests you ease up on showering.)