Fevers, aches, and sore throats are spreading throughout the country as another flu season begins. The Center for Disease Control and Prevention advices flu vaccinations and healthy hygiene practices. Traditionally it has been encouraged that hands be washed thoroughly with soap and hot water. However, National Geographic recently released an article that dispelled the use of hot water to kill bacteria while washing hands. The article cites a study conducted by Vanderbilt University that found while hot water does indeed kill bacteria, it requires temperatures that far exceed what is used for hand washing. 212°F is needed to disinfect water from pathogens but hands are usually washed in temperatures ranging from 104°F to 131°F. Therefore, the hot water used to wash hands will not significantly reduce germs. In fact, it is believe that it may do more harm than good because it can remove the upper layer of skin and make the body more susceptible to bacteria. And in addition to it having no health benefits, warm water is also very wasteful. It has been estimated that Americans contribute 6 million metric tons of CO2 emissions annually by washing their hands with hot water. This is comparable to the emissions of an astounding 1,250,000 vehicles.
Simple lifestyle changes, if made by a large population, can considerably benefit the environment. This includes unplugging technological devices when not in use, carpooling with friends and family, turning off the faucet while brushing one’s teeth, and purchasing local foods. Now we have something additional to add to that list: wash your hands with cold water. But this is not the only place to shift the use of hot water to cold. In the United States 15% of energy used in households can be attributed to hot water heating. A Norwegian study found that reducing temperatures from 104°F to 86°F while washing clothes, will reduce energy consumption by 30% while still just as effectively cleaning the clothes. This heat reduction is not only sustainable but also cost effective. For every 10°F drop, approximately 3-5% of water heating costs can be cut. So, stay healthy and be sustainable. Get your flu shot and wash your hands well with soap. Do not, however, turn that hot water knob. You’ll save a few bucks and reduce your carbon footprint!