Remember way back to high school science class. That may be longer for some of you, but bear with me. A full explanation is coming! A calorie is the energy to raise the temperature of 1 gram of water by 1 degree Celsius. When most people refer to Calories, they are actually talking about kilocalories. So when you eat that Hardee's Monster Thickburger, you are actually eating 1,420,000 calories! And when a 150 pound person runs 3 miles at 10 minutes per mile, they burn 324 Calories, or 324,000 calories.
So, considering that the definition of a calorie is based on raising the temperature of water, it is safe to assume that your body must burn calories when it has to raise the temperature of water to body temperature. Since your urine is not coming out ice cold, your body must be raising the temperature; therefore, calories are being burned. But by how much?
Let's take a tall glass of ice water (most glasses are 2 cups, so 16 ounces). Here are the facts:
- The temperature of the water is 0° C
- Body temperature estimated at 37° C
- 1 calorie to raise 1 g of water by 1° C
- There are 473.18 g in 16 oz. of water
So your body must raise 473.18 grams of water by 37 degrees Celcius, which burns 17,507.66 calories. Remember the difference between the two? That means it's approximately 17.5 Calories your body burns every 16 oz. of ice cold water you drink.
Doesn't seem like a lot, does it? But wait! That's only 2 cups of water! You drink more than that (or at least you SHOULD be drinking more than that). Daily recommended water intake is 8 cups, and a cup is 8 ounces (I believe that active people should drink at least a half a gallon though, especially if trying to lose fat). So that's an extra 70 Calories you burn every day just by drinking ice water. If you drink that half a gallon every day, that's 280 extra Calories burned! Over time those extra Calories really add up too!
