Should you use warm or cold water to wash your hands?


Washing our hands is something that we do every day and it’s an incredibly important part of keeping bacteria and viruses from spreading and potentially causing harmful illnesses.

Whilst most of us may believe that warm water is better at helping to keep your hands cleaner rather than cold water, a new study has found that water temperature may not be as important as first thought.

A team of scientists from Rutgers University, based in New Jersey, carried out the research which looked to measure the amount of bacteria that is still present on hands when using water at different temperatures.

Each of the 20 participants was asked to wash their hands 20 times with water that was at 15C (59F), 26C (79F) or 38C (100F) and use varying amounts of soap

Before each test, the participants’ hands were covered in harmless bacteria to allow the researcher to measure the amount of bugs that were removed after washing.

The results showed that using colder water (15C) removed just as much bacteria and left hands as clean as using water heated to 38C, even with the differing amount of soap being used.

Published in the Journal of Food Protection, Prof. Donald Schaffner said: “People need to feel comfortable when they are washing their hands but as far as effective [goes], this study shows us that the temperature of the water used did not matter.”

Whilst the NHS advises that either cold or warm water will do the trick of cleaning your hands properly, official guidelines from the US food industry state to use hot water although it is hoped that this new approach of using cold water could help restaurants cut their electricity bills.

The team at Rutgers University did concede that the size of the study is small and there should be more extensive studies carried out to find out the best way of removing harmful bacteria from hands, but next time you only have access to cold water at least you know that your hands will still be clean.

Find out how to wash your hands properly here