This is the first question in Doctor Joshua’s Medical Fact or Fiction series:

Does the temperature of the water you drink affect the effects it has on weight loss, or is that just a myth?

Doctor Joshua’s Answer:

In theory, if you drink cold water, it will cause your body temperature to drop, and in turn, your body must produce more heat and conserve heat to keep the body temperature stable. The body produces heat by various physiological means such as increasing muscle tone, contracting surface blood vessels, reducing perspiration and so on.

In order to evaluate whether drinking cold water might actually help you lose weight, let’s look at this from a thermodynamic point of view:

1 kcal = the energy it takes to raise the temperature of 1kg of water by 1°C.

Drinking 1 liter (about one quart) of ice-cold (0°C) water then heating it up to 37°C would require 37 kcal of energy.

Fat contains 9 kcal of energy per gram. 37 kcal would correspond to about 4 grams of fat.

Therefore, considering only the thermodynamic qualities of water, and assuming you would burn fat to produce the heat (in fact, you’d be burning muscle, too), drinking one liter (about one quart) of ice-cold water would result in you losing all of 4 grams (0.14 ounces) of fat.

In conclusion, I’d venture to say that drinking cold water does not seem to be much help in losing weight!

Doctor Joshua’s Verdict: FICTION