By Zahra Barnes
September 4, 2016

If you're wondering whether drinking cold water to lose weight is a good idea, you're in the right place. Welcome to another installment of SELF.com's weight-loss myth busters. Previous topics have ranged from whether strength training or cardio burns more calories to the sad-but-true fact that, no, drinking red wine every day doesn’t magically make you weigh less, and whether spiking your H2O with lemon can really help you shed pounds. We poured cold water on that last idea, but now it's time to discuss that cold water itself—specifically, whether downing an icy glass of the stuff actually helps you burn more calories than you would if you went for a room temperature pour. And actually, the answer is yes, it does. But not as much as it may seem.

Before diving in, if you're interested in this topic because you'd like to burn calories for weight loss, a few things to note. Health and weight loss look different for every person, and if you want to lose weight, what works for you might not work for others, and vice versa. Beyond that, it’s incredibly important to think about why you actually want to lose weight—and whether doing so is a healthy decision. For example, if you have a history of disordered eating, you should talk to your doctor before starting a new eating plan. Even if you don't have that history, setting healthy, realistic goals and expectations is key. It's impossible to always control every factor that goes into weight loss, like your sleep, stress, and hormones. What you can control? Treating yourself with kindness and listening to your body as much as possible.

Now, here's the truth about cold water and calorie burn.

This rumor gained traction over a decade ago because of a study with surprising results.

In 2003, a research team in Germany studied 14 people and found that if the participants drank ice cold water, they could boost their caloric expenditure by about 30 percent for over an hour. Meaning, "If you could chug your way through two liters of cold water, you could burn about an extra 100 calories per day," Rachele Pojednic, Ph.D., assistant professor in the nutrition department at Simmons College and professor at the Harvard Extension School, tells SELF. "That’s a lot of freezing cold water to drink." It is—about a large soda bottle's worth—but an extra 100 calories per day is a pretty major deal for something that doesn't require much effort.

But the study raised other researchers' suspicions.
"Lots of researchers saw this study and said, 'Wait, there have been other studies looking at the thermogenesis of food [how many calories it takes to metabolize the food, or in this case heat the water up to body temperature], and those studies didn't show anything or just a tiny amount [of calorie burn].'" The results didn't make sense, so other studies tackled the subject and found that the 2003 study measured calorie expenditure in a flawed way. "When they redid these studies, they found there was a teeny tiny effect that wasn't statistically significant," says Pojednic.