This summer, I was mocked for my theory that drinking hot tea (or other hot drinks) helps cool you off. My only evidence is anecdotal: I lived in West Africa and the folks there, especially in the very hot areas, have a whole afternoon ritual of drinking up to three or four servings of hot tea. I would love to learn that I am right, so that I can throw the facts back into my friends’ faces. You know how it is. Thanks.
If you stay still and drink hot tea in the shade, you will cool off more than if you keep working out in the sun.
And if it’s hot out, your body needs water.
The main purpose of drinking liquids to keep cool is that you end up sweating the water out, and it cools you by evaporation. I don’t have the numbers handy, but the heat absorbed by vaprising water is much greater than the heat that would be stored in liquid water of a particular temperature. Hence, cold drinks will cool you off a little more, but not much. What’s important is that it’s water.
On the other hand, isn’t tea loaded with caffeine? I always thought caffeine was a diaretic and leeched water out of the body.
Caffeine is a diuretic, but has no effect on perspiration, only urination. As to evaporation of sweat, this is the key way that we cool off. Runners cool off through evaporation and conduction primarily. Hot drinks will cause more perspiration; hence, theoretically they will have a greater cooling effect. There may be offsetting physiological events, however. (I don’t know of any.)
The body needs to stay at 98.6 degrees, but metabolism within the human body constantly produces heat. When the ambient temperature is below the body temperature, a balance is relatively easy to achieve. As the ambient temperature approaches 98.6, the body needs help cooling off: it perspires so that the moisture evaporating from the surface of the skin uses some of the heat from the body in order to do so. As the ambient temp exceeds 98.6, it obviously becomes more and more difficult for the body to maintain its temperature.
The bottom line is maintaining the 98.6 in the face of internal “combustion” and external heat. Therefore, the bottom line is that hot liquid raises your body temp and makes it harder for your body to maintain its temp, and cold liquids lower your body temp, aiding your body in its fight to stay at 98.6. Therefore, in say 100 degrees F, 8 oz. of cold water will do more to relieve you from the heat than will 8 oz. of hot water.
The hot liquid does replenish the liquids lost to perspiration, but its affect on your body’s internal temp must now be overcome along with the body’s internal combustion, and has less net effect on cooling than cold liquid.