I was at the gym earlier today and I overheard two girls chatting about tricks to lose weight. One told the other one: “You know that when you drink ice cold water your system burns a massive amount of calories to bring it to the body’s temperature!”
I shook my head in disappointment (and I think they noticed) because, unfortunately, this is a myth deeply rooted in people’s mind and not exactly on point.
In a way, it is true that when you drink ice cold water, your body uses energy (i.e., calories) to raise the liquid’s temperature to match body's temperature.
However, the calories consumed are so few that it’s almost non relevant at all. Certainly not nearly enough to cause any appreciable decrease in your body fat.
Let’s do a little bit of math to better understand what we’re talking about.
Let’s say you drink a 8-ounces (240 grams) of ice-cold water at around 4°C your body will expend calories to bring it to body temperature, which is about 37.5°C. That’s a difference of 33.5˚.
To raise 1 gram of water of 1˚ C, 1 calorie is necessary (but be aware, in scientific terms this is a “little” calorie, 1 food calorie - those we usually refer to - is equal 1,000 of this “little” calories).
Raising 240 grams of water by 33.5˚ will take: 33.5 x 240 = 8,040 little calories or 8 food calories (also known as kilocalories).
I won’t say that 8 calories is nothing but if you think that one celery stalk has 10 calories, you can easily see that it’s highly unlikely that you’ll lose any fat just by drinking ice cold water.
Even if you drink 10 glasses of 8-ounces ice cold water throughout the day you’ll burn 80 calories, again not bad, but if you think that 1 pound of fat is equal to 3,500 calories...well, I’ll let you do the math.