Handwashing What better protects us from infections? Cold or hot water?

Is it really more effective to wash your hands with hot water??
Many of us have learned at an early age that we need to wash our hands with hot water to remove existing germs. Researchers have now found that the warm water temperature is not critical to successful cleansing. It is more important to wash your hands thoroughly and with enough soap.

Researchers at Rutgers University-New Brunswick, New Jersey found in their study that there is no significant difference in cleaning hands with cold or warm water. So no warm water is needed to effectively rid your hands of germs. The experts published the results of their study in the journal "Journal of Food Protection".

Washing your hands is important for bacterial reduction. But does it matter if we use warm or cold water? Scientists tried to answer this question in their current study. (Image: Alexander Raths / fotolia.com)

Hot water when washing hands no longer removes germs
Small children are often taught to wash their hands with hot water to cleanse them of dirt and germs. But is there any scientific justification for this statement? New research indicates that hot water does not remove more germs than cold water when washing hands.

So far, a cleaning with hot water was advised
U.S. The Food and Drug Administration (FDA) suggests that cleaning the hands with warm water is more effective at eliminating germs compared to cleaning with cold water. The reason for this is that hot water leads to more lather and kills germs better.

Which factors were investigated?
There has been some suspicion for some time that hot water is not really needed for the removal of germs, say the authors. The current investigation suggests that cold water can kill germs just as effectively as hot water. The new study investigated the effects of various factors such as soap volume, water temperature, foam time, and the hand wash effect of the soap, the researchers add.

Which bacterium was removed from the hands?
At baseline, participants used one milliliter of non-antibacterial soap to cleanse for five seconds at a water temperature of 38 degrees. The investigated bacterium in the hands of the subjects was ATCC 11229, a strain of Escherichia coli, explain the physicians.

How did the experiment go??
The scientists studied the effects of hand washing with cold and hot water on 20 volunteers, consisting of 10 men and 10 women. Each study was replicated twenty times over a six-month period. During this time the participants washed their hands in water with temperatures of 16 degrees, 26 degrees and 38 degrees, explain the experts. The amount of soap used was different. The participants washed their hands with 0.5 milliliter, 1 milliliter or 2 milliliters of soap.

Water temperature has no significant effect on bacterial reduction
The use of an antimicrobial soap was not much more effective than washing with a standard commercial soap, say the authors. In addition, it should be noted that the water temperature has no significant effect on bacterial reduction. Whether the water temperature was 38 degrees or 16 degrees, there was no difference in bacterial reduction, the physicians add. The study also found that even washing hands for less than ten seconds is sometimes effective enough to eradicate germs. The most important result, however, was that the temperature of the water used in the elimination of germs did not matter, says author Donald Schaffner of Rutgers University. (As)