Does Drinking Cold Water Burn Calories and Help Weight Loss?

When it comes to health and fitness there are not many absolute truths. Topics that seem fairly straightforward often result in confusion or cause people to have opposing viewpoints. In some cases, differing opinions can all be correct, but each one may only true under certain circumstances. However, when it comes to the question of whether drinking cold water burns more calories than drinking warm water, there is a scientific truth.

The interesting thing about this issue is the question can be easily answered by examining the definition of a calorie. Merriam-Webster Online defines a calorie as "the amount of heat required to raise the temperature of one kilogram of water one degree Celsius." This may sound a little confusing, but with a little simplification and some measurement conversions, it becomes obvious that drinking colder water does in fact burn more calories.

The most important part of this definition is that calories are defined by the amount of energy it takes to raise the temperature of water within your body. To calculate the amount of calories burned with US measurements, we need to do a couple conversions.

First, 1 kilogram (or 1000 grams) of water weight is equal to 1 liter in volume, which corresponds to 33.8 ounces or 4.2 glasses of water (8oz each). To convert the temperature of water, you can use the following equations: 1°Celsius = (Fahrenheit temperature - 32) divided by 1.8 or 1°Fahrenheit = (Celsius temperature multiplied by 1.8) + 32.

A glass of ice water is around 38°Fahrenheit or 3.3°Celsius, although this varies depending on the temperature and the amounts of ice and water in the glass. The normal temperature of the human body is about 98.6°F or 37°C, although there is some variance here as well. The final piece of information that explains why colder water burns more calories is that the human body naturally increases the temperature of consumed water to your normal body temperature.

In other words, if you drink cold water, your body will spend energy (burn calories) to warm it up. For example, say you drink 8.4 glasses of ice water (3.3°C) per day, which is just over the typical recommendation of 8 glasses per day. On a side note, the actual requirement varies from person to person and some medical organizations recommend more than 8 glasses of fluid per day¹.

From the definition of a calorie, we can figure out that the water must be increased by 33.7°C (37°C - 3.3°C). This means your body burns 33.7 calories for every 1000grams or 4.2 glasses of (3.3°C) water consumed. Therefore, drinking 8.4 glasses of 3.3°C or 38°F water will burn about 67.4 more calories than drinking the same amount of water at 37°C or 98.6°F (regular body temperature).

Based on human physiology and the definition of a calorie, we can see that without a doubt, drinking colder water does burn more calories. So now the important question is how does this impact your ability to lose weight?

It is important to note that the above calorie burning numbers were found by comparing cold water to water at body temperature. Realistically, few people drink 98.6°F water, so it is more appropriate to compare drinking cold water to drinking water at room temperature. Since room temperature water is generally around 60-75°F, the number of extra calories burned by drinking cold water will not be as large.

However, even when comparing ice water to room temperature water, you still end up burning approximately 30 more calories a day by drinking ice water. 30 extra calories burned in a day may not seem like much, but it adds up over time.

Over the course of a year, 30 extra calories per day adds up to total 10,950 calories, which translates to a little over 3 pounds of fat. Therefore, just by drinking ice water instead of room temperature water, you could potentially lose 3 pounds over the course of a year.

This is not a huge amount, but it does show that you can create a small increase in weight loss just by drinking cold water. However, it is important to point out that the calorie burning benefits of drinking cold water do not come anywhere close to the calorie burning and health benefits you get from eating right and exercising, so it is important to keep things in perspective.

I would never design a weight loss program based solely on drinking cold water, but considering that drinking water is something you should do anyway, you may as well keep your water on the cold side. You may as well benefit from the little extra calorie burning, especially when it requires so little effort.

References:

1. Mayo Clinic Staff, Water: How much should you drink every day?, MayoClinic.com

http://www.mayoclinic.com/health/water/NU00283

2. Merriam-Webster Online - http://www.merriam-webster.com/dictionary/calorie

Additional Source:
14 years of experience and education in health and fitness