Can cold showers really help you lose weight?

It used to be that women took cold showers when they were feeling hot (wink wink). But, increasingly more women are taking the plunge for their health—with research linking them to lower rates of depression and anxiety, reduced pain, less inflammation, better immune function, and increased productivity.

But can cold showers really help you lose weight? The internet certainly seems to think so, with proponents saying that cold showers raise your metabolism and help you burn more fat throughout the day.

And, it turns out, there is some scientific basis to the claims. After all, cold temperatures have been repeatedly shown to increase activation of the body's energy-burning brown fat.

In one Harvard study, people who spent 10 days straight in rooms cooled to 60.8 degrees significantly increased activity levels of their brown fat. And people who have higher amounts of brown fat do have lower body mass indexes, according to a study published in the New England Journal of Medicine.

Here's how it works: The body stores excess calories in the form of white fat. When most of us try to fight fat, this is what we're up against. However, the body also contains a completely different kind of fat, called brown fat, which actually burns calories in order to maintain the core body temperature you need to live and be healthy, explains Nitin Kumar, M.D., an obesity and weight management specialist at HSHS Medical Group. Babies tend to have high levels of brown fat, but as we age, those levels decline. What's more, activation of the brown fat we have also declines, and it's when brown fat is activated that it turns into a calorie-torching machine.

But just because cold activates brown fat and brown fat is associated with lower weights doesn't necessarily mean that icy showers will have you dropping pounds like whoa. "You would have to spend a good amount of time in cold water to get even a small benefit," Kumar says.

How long are we talking, exactly? Well, in one study published in the Journal of Clinical Investigation, people who spent two hours per day in 66-degree temps lost one to two pounds of over a course of six weeks. And, no, we aren't suggesting daily two-hour-long cold showers.

"I have not seen any study showing major weight loss success by adding in cold showers," says Spencer Nadolsky, M.D., a board-certified family medicine physician, diplomate of the American Board of Obesity Medicine, and author of The Fat Loss Prescription. "Many are touting this as being revolutionary, but it's not. It's not going to be a miracle breakthrough method for you."

"Taking a daily cold shower may help you marginally at best, and unnecessarily torture you at worst," Kumar says.

That said, if you're determined to give it a try, just make sure you're being safe about it. "Try this only if you don't mind the discomfort or actually enjoy it," Nadolsky says.

Translation: if it hurts, get out! Stay in for 10 to 15 minutes max, and if anything goes numb or turns white or purple before then, get out. Same if your breathing slows down or becomes difficult. That might sound extreme, but you've got to play it safe with potential frostbite and hypothermia, he says.