Are there some baths for weight loss that actually work? Can you use a hot tub to lose weight? And if a hot bath with Epsom salt is supposed to help, I should be thin as a rail, but the truth is that I could stand to lose five pounds. So what gives?
A sauna burns 300 calories in 30 minutes, while a hot tub and Epsom salt bath both burn 51 calories in 30 minutes. Although science can’t prove a bath leads to long-term weight loss, passive heating is a type of bathing that might prove beneficial in the future.
Download the chart above that shows how many calories you’ll burn with different baths.
But beware: the devil is in the details. So let’s dive into 5 types of baths rumored to lead to weight loss and see what the research says about each:
1. Can you use a hot tub to lose weight?
A 150-pound person sitting in a hot tub at about 100 degrees Fahrenheit for an hour burns 102 calories. Hot tubbing burns only 32 more calories per hour than sitting on the couch. However, a hot tub offers benefits that indirectly affect weight loss like decreased cortisol, increased metabolism, and improved sleep.
Of course, you wouldn’t want to stay in the hot tub that long for a variety of reasons, including dehydration. But keep that calorie count in mind as we explore the burn from other bath types.
In any case, it’s not the calories that make hot-tubbing beneficial for weight loss. It’s the secondary, proven benefits.
So if you’re thinking of buying a hot tub, you’ll want to read How to Buy a Hot Tub: Ultimate Guide. You can save thousands of dollars with the tips in this post. And if you simply want to transform your bathtub into a hot tub, we’ll show you how you can do it quite inexpensively. Read How to Turn Your Bathtub into a Jacuzzi.
How else does hot-tubbing affect me?
When I’m super-stressed, I tend to make a bee-line for the potato chips. That’s because a hormone called cortisol has hijacked my otherwise sensible mind. Cortisol is the hormone our bodies release when we’re tense and under pressure.
Hot tubs can lower cortisol
Cortisol makes us crave foods that lead to weight gain. It prevents muscle build-up and increases belly fat. It also makes us feel tense and out of control—and it makes me need potato chips. Now!
One study looked at the impact of hot tubs and balneotherapy on cortisol levels. As part of a review of the scientific literature, researchers in Italy reviewed 10 studies that looked at the impact of spa therapy (hot tubs) on salivary cortisol levels.
In eight of the studies, subjects showed a statistically significant reduction in cortisol levels. They concluded that spa therapy does reduce cortisol levels.
When we’re more relaxed, studies show that we’re less driven to eat as many calories as often. Makes sense, right?
Hot baths can improve metabolism
A recent study shows that hot water baths can improve metabolism. And better metabolism is definitely associated with weight loss.
Hot tubs help us sleep
The other real but indirect way that hot tubbing can help with weight loss is that it paves the way to a good night’s sleep. So try to get into a hot tub in the evening as part of your wind-down routine.
When we’re sleep-deprived, we get a double whammy: First, a hormone called ghrelin increases, and this hormone makes us hungry. Second, our metabolism slows down, and that makes the calories we do consume more likely to stick around your waistline.
Experts recommend getting into the hot tub two hours before you want to get into bed. Soak for 20-30 minutes. The water will raise your temperature, and the drop in temperature when you get out will relax your body and prepare you for sleep.
The National Sleep Foundation explains that when your body temperature falls, it cues the onset of sleep:
Remember, you ultimately have to get out of the tub. Doing so sets you up for a cool-down as you dry off and the water on your skin evaporates, and that sets the stage for sleep. Try to schedule this bath for 60 to 90 minutes before bed, so that your body temperature has a chance to drop before you jump into bed and pile on those cozy blankets.
A recent study showed that even one night of poor sleep can trigger fat storage and muscle breakdown.
Turn your bathtub into a hot tub
Are you thinking, “Hey, I don’t even have a hot tub!”? Well, there’s no need to let that get in the way.
You can easily and pretty cheaply turn your regular bathtub into a hot tub with a Jacuzzi Bath Mat. (Here’s my favorite one.)
But is a hot tub the best type of bath for weight loss? Let’s take a look at some other options.
2. Does an Epsom Salt Bath Cause Weight Loss?
A 150-pound person will burn 51 calories in 30 minutes in a 100 degree Fahrenheit Epsom salt bath. The calories burned are a function of the water temperature and not the presence of Epsom salt in the water. However, Epsom salts yield secondary benefits like improved sleep that can contribute to weight loss.
In any case, these days you can’t go to the grocery store without seeing a huge display of Epsom salts for sale. And I have to say I always grab a bag of Himalayan Pink Epsom Salt and a bag of the Eucalyptus Epsom Salt.
Though called “salt,” Epsom salts are made from a different compound than regular table salt. Epsom salt was discovered in a town called Epsom in England about 400 years ago.
To me, this type of salt looks just like sea salt, with large crystals. Epsom salt is a chemical compound made of magnesium, sulfur and oxygen. It’s the magnesium that some say has a soothing impact on muscles, though most scientists do not believe that the magnesium penetrates the skin. I’m a firm believer that anecdotal evidence is sometimes a decade ahead of the science, so on this front, time will tell.
I like to dissolve two cups into a warm bath. It definitely relaxes me and I love the aromatherapy that comes with it. Plus, it’s supposed to help with sore muscles.
Despite the lack of hard evidence, people swear that Epsom salt baths help with everything from fibromyalgia to arthritis to better sleep. My favorite for deep relaxation is Dr. Teal’s Pure Epsom Salt Soaking Solution for Pre & Post Workout. (I don’t even work out that much, but I still love this one.) You can get it on Amazon.
So is it just a myth that Epsom salt baths cause weight loss?
An Epsom salt bath is probably not going to melt away the pounds, but oral consumption of magnesium sulfate does show promise for reducing fat. A study out of Iran found that oral ingestion of magnesium sulfate inhibits complications from obesity.
Of course, if you’re thinking of trying magnesium sulfate as a supplement to promote weight loss, consult your doctor first. And note that you can get magnesium by eating spinach and almonds.
Bathing in magnesium sulfate falls into a similar category as hot tubbing. The benefits are most likely indirect and include relaxation and improved sleep. I know that for me, if I’ve had a good night’s sleep, I’m much less likely to pig out. And when I’m short sleep, I crave fatty foods. In this very indirect way, Epsom salt baths might help you eat better.
The bottom line is that while Epsom salt baths are relaxing and might ease muscle pain, don’t count on them to melt away the pounds.
3. Can a Steam Bath Help You Lose Weight?
A bather might lose 1-2 pounds in a steam room heated to 100-115 degrees Fahrenheit. However, the weight loss is simply from dehydration, not loss of fat. As soon as the bather hydrates, the person will regain the weight lost.
While not a traditional bath, I included a steam bath on this list only because you’ve got to wonder if all that sweating burns fat. I usually only stay in the steam bath 10 minutes, before I’m desperate to get out.
But, I guess I’m not missing out on any weight loss. Investigating the literature leads me to the conclusion that a steam bath is not the bath to go for weight loss either.
Don’t get me wrong. You’ll sweat buckets—usually, these steam rooms are heated to around 110-115 degrees Fahrenheit. So you will lose a little weight. Unfortunately, it’s just water weight, which is much different than losing pounds made out of fat.
As soon as you get out of the steam bath and drink some water, you’re back to square one.
And you should definitely drink, drink, drink while you’re taking a steam bath and after. Otherwise, you can easily get dehydrated.
Secondary Benefits from Steam Baths
This said, there is a wee bit of research to support secondary benefits of a steam bath that could help with weight loss. These include reducing cortisol, the hormone that is released when we get stressed.
Also, just as our core body temperature drops when we get out of the hot tub, the same can be said for leaving the steam bath. And when our temperature drops like that, we can get sleepy. So if you steam before bed, maybe you’ll sleep better. And better sleep is definitely correlated with consuming fewer calories in fat.
And of course, there are other benefits that come with taking a steam bath. Your body gets rid of toxins. A steam bath can clear toxins, improve the look of your skin, and help with post-workout muscle recovery.
But don’t stay in there any more than 20 minutes. And if you’re pregnant, have cardiovascular issues or low blood pressure, a steam bath is definitely not for you.
4. Does Passive Heating Help With Weight Loss?
A passive heating bath burns 140 calories an hour and lowers blood pressure, decreases inflammation, and prevents spikes in blood sugar. Subjects takes passive heating baths in an experimental setting. The goal is to raise core body temperature by 1.8 degrees Fahrenheit, or 1 degree Celcius.
Okay, so here’s where the science gets really interesting.
Scientists at Loughborough University studied 14 men. The subjects either soaked in an extremely hot bath that was 104 degrees Fahrenheit for a whole hour. Or some went cycling for an hour instead.
The researchers found that in the hot bath, the men burned 140 calories in an hour. This is about as many calories as the men would have burned if they’d walked for 30 minutes. When the men cycled for an hour, they burned many more calories.
Hot Baths Reduce Blood Pressure
But what interested the researchers most was that in the hot bath, the men showed a better anti-inflammatory response than when they cycled. Their blood sugar levels didn’t spike as much. This study was followed up by research out of the University of Oregon that found hot baths reduce blood pressure.
So it seems that passive heating is an area that researchers will continue to explore for its benefits. However, subjects in these types of studies frequently say that passive heating isn’t realistic—that they could never keep up the regimen because it’s just too uncomfortable. And anyway, the problem with trying to use passive heating at home is that it’s too hot to try without medical supervision.
But the general idea holds true: The warmer your bath, the more calories you’ll probably burn.
5. Can a Cold Water Bath Help With Weight Loss?
Some researchers claim that simply by shivering, you can burn about 400 calories an hour. However, it is yet to be scientifically proven that cold water bathing burns Brown Adipose Tissue (BAT), otherwise known as Brown Fat.
To put this in perspective, 400 calories is like 9 oranges or 3/4 cup of Ben and Jerry’s Chocolate Chip Cookie Dough ice cream.
People the world over immerse themselves in freezing cold ice baths hoping this will change their lives. Many of these people are athletes who find ice baths aid in post-workout recovery. But some are simply overweight folks hoping to shiver themselves skinny.
You can lose more weight in the water than on dry land
About a decade ago, a NASA scientist named Ray Cronise was trying to lose weight. At the time, he consumed about 12,000 calories a week. Then one day, Cronise heard Michael Phelps, the Olympic swimmer, interviewed. Phelps said that the ate 12,000 calories a day and swam three hours a day.
Cronise thought something was amiss. Even with all that swimming, Cronise thought Phelps should be obese, since he was eating so many calories.
But then Cronise had an Aha! moment. He formulated a theory: Phelps’s ability to eat so much without gaining weight must be because he spent all day in a pool. Cronise hypothesized that the pool water must extract more energy from the swimmer’s body than does the air.
He called his theory thermogenesis.
What is the impact of cold on body fat?
Back in Alabama where he lived, Cronise honed his theory. He developed a contraption that allowed him to test energy in water, and he invited journalists and others to try it out.
Well, so much for Southern hospitality.
After initial greetings, Cronise would strap a snorkel-like contraption onto his guest, ask the guest to jump into his pool, then weigh the poor sucker down with an anchor. Cronise then measured various biomarkers hoping to figure out the impact of cold on fat.
Cronise concluded that water is 24 times more thermally conducive than air, so you can lose much more heat when you’re submerged in water.
Timothy Ferriss was so impressed with Cronise’s research that he started cold water bathing regularly. Ferriss also showcased Cronise’s work in his book, the 4-Hour Body Hack: An Uncommon Guide to Rapid Fat Loss, Incredible Sex and Becoming Superhuman.
Cold water bathing officially took off.
Brown Fat: A Cold Case
Over the past decade, many researchers have hypothesized that exposure to cold might activate Brown Adipose Tissue (BAT), otherwise known as Brown Fat. As opposed to white fat that accumulates around the belly and correlates with metabolic and inflammatory diseases, brown fat generates heat by burning calories.
Unfortunately, though, it’s a cold case: no research to date has proven the case for cold exposure and Brown Fat.
Still, this hasn’t stopped cold water enthusiasts and ice bath lovers from following their bliss—and swearing that they fit into their hot jeans as a result.
Are you still holding out hope that science will prove that cold exposure activates brown fat to burn calories? If so, no one could blame you.
The good news is that research shows that cold water baths do have health benefits. These baths activate the anti-inflammatory response and improve circulation. For a closer look into the science of ice baths, read The Bathtubber’s guide to ice baths here.
What’s the Skinny on Baths for Weight Loss?
The bottom line is that anecdotal evidence says, “Hell, yeah! You can bathe to lose weight.”
The research says that many baths promote promising secondary benefits associated with weight loss.
But as for a solid correlation between bathing and sustained weight loss over time? Time will tell, or in other words, the proof will be in the pudding.
Did someone say pudding?!
Will a bath help with menstrual cramps?
A hot bath can help relieve menstrual cramps by relaxing the uterine tissue and the pelvic muscles. During menstruation, the body is shedding the uterine lining. This causes cramping. A warm bath will increase blood flow by raising your internal body temperature. A bath also warms more body surface than a heating pad. To ease cramps, try gentle stretching and massage in the bathtub. Yoga poses can feel good. Also, use a tennis-sized rubber ball under your body to reach hard-to-get trigger points.
Will a bath help with constipation?
Dr. Bruce M. Belin, Board Certified Colorectal Specialist at CSGA in Lexington, Kentucky says, “One of the big things for bowel functions is respecting circadian rhythms. Most people have bowel movements in the morning. So if you get up super early and take a warm bath, that can help.”