炎炎夏日,热茶和冷饮哪个更解暑?
While you might be tempted to reach for a cold drink to help cool you down in such hot weather, surprisingly hot drinks such as teas and coffees may actually be more effective. A study in 2012 by researchers from the University of Ottawa looked at the effect of drinking hot drinks on body temperature. The results revealed that a hot drink can cool you down, but only in dry conditions. Speaking to the Smithsonian Mag, Dr Ollie Jay, one of the authors of the study, explained: "If you drink a hot drink, it does result in a lower amount of heat stored inside your body, provided the additional sweat that's produced when you drink the hot drink can evaporate." Essentially, when you ingest a hot drink, you start sweating more. If the sweat is able to evaporate, it actually cools you down, more than compensating for the added heat to the body from the fluid. While sweating can be embarrassing, it's an essential body function to help keep us cool. As the sweat evaporates from the surface of your skin, it removes excess heat by converting the water from a liquid to a vapour. However, in humid conditions this cooling effect is less effective, so drinking hot drinks won't help to cool you down. Dr Jay explained: "On a very hot and humid day, if you're wearing a lot of clothing, or if you're having so much sweat that it starts to drip on the ground and doesn't evaporate from the skin's surface, then drinking a hot drink is a bad thing." "The hot drink still does add a little heat to the body, so if the sweat's not going to assist in evaporation, go for a cold drink." Overall, the lesson learned is that in hot, dry conditions, drinking hot drinks will cool you down, but if you're in a humid location, it's best to stick to cold beverages. |