You may already take advantage of moist heat therapy at home, showering or bathing to warm your joints and loosen your muscles. Could adding minerals, such as Epsom salt, enhance that relief and improve arthritis symptoms?
The short answer: maybe, but the research is mixed.
In this article, we’ll review what mineral baths are, what the latest studies say about the effectiveness of mineral baths for different kinds of arthritis and pain, and provide tips for giving yourself a relaxing mineral bath at home.
What Is a Mineral Bath?
Mineral baths are warm (not hot) and contain at least 1 gram of dissolved minerals in each liter of water. The distinctive scent of many mineral baths is from sulfur, but magnesium is also present in most natural springs. Other minerals may also be present.
Since ancient times, people in search of relaxation or pain relief have taken to the waters, immersing themselves in warm mineral baths at natural springs. There’s even a word, balneotherapy, for the therapeutic use of bathing in mineral water, usually offered at spas.
Many people living with arthritis or other chronic pain keep Epsom salt as a bathroom staple, sprinkling it in the bathtub for extra relief or relaxation.
What Is Epsom Salt?
Epsom salt is a compound of magnesium, sulfur, and oxygen — it’s not at all like table salt. It’s named for a town in England where it was discovered in natural underground springs in the early 17th century. You can find Epsom salt in grocery and drugstores. Epsom salt is not the same as Dead Sea salts, which is a combination of minerals that are found in the Dead Sea in Israel. When dissolved in water, Epsom salt releases magnesium and sulfate, key ingredients in most spa mineral baths.
Mineral Baths vs. Regular Baths for Arthritis
There are many physical benefits to bathing in warm water when you have arthritis or chronic pain. The heat from the water is very soothing to stiff joints. And the practice of self-care and stress relief is very important for managing chronic diseases like arthritis.
“The thermal and mechanical benefits of warm water are well-known and include muscle relaxation, improved joint mobility, and reduced pain,” says Maura Daly Iversen, PT, DPT, SD, MPH, FAPTA, associate dean of clinical education, rehabilitation, and new initiatives at the Bouve College of Health Sciences at Northeastern University in Boston, Massachusetts.
“Less evidence exists about the chemical benefits of mineral baths,” she adds. “Some studies show mineral baths can have an anti-inflammatory effect in patients with arthritis by increasing certain cells that mediate inflammation and by enhancing circulation and breathing.”
Specifically, some research has shown decreases in the inflammatory chemicals interleukin-1 and tumor necrosis factor (the targets of some arthritis medications), along with increases in endorphins, the body’s natural pain killers, after mineral bath soaks.
Still, studies don’t all agree on the chemical impact — or even whether magnesium or other minerals can be absorbed through the skin.
In other words, whether the minerals in the baths (from a natural spring, a high-end day spa, or poured from a jar into your bathtub at home) have additional benefits for relieving arthritis symptoms beyond the relaxing act of bathing is not completely clear and is something researchers are still studying.
What Studies Show About Mineral Baths
Several studies conducted at spas around the world offer some intriguing clues as to who might benefit from using mineral baths to help manage arthritis symptoms.
In a 2019 study from Turkey, a higher percentage of older people with knee osteoarthritis improved with mineral baths and physical therapy than with PT alone. When doctors in Turkey analyzed the real-life experience using mineral baths in patients with a variety of types of arthritis, only those with hip osteoarthritis did not improve significantly in either pain or functioning.
“Since the hip is a deep joint, it may not respond as well [to mineral bath therapy] as joints closer to the surface,” says Dr. Iversen.
Rheumatoid arthritis (RA)
Published studies have shown inconsistent improvement in pain and morning stiffness in RA with mineral baths, according to a 2018 review. However, some individual research trials have shown benefits.
In a 2016 study from Portugal, people with rheumatoid arthritis functioned better with 21 days of mineral baths (some including water exercise) than with standard treatment. In a 2018 study from Turkey, people with RA taking disease-modifying antirheumatic drugs were rated as more improved by themselves and their doctors when two weeks of spa therapy was added. Benefits lasted six months but tapered off to mild improvement by 12 months.
In a study that compared mineral baths to warm tap water baths, Italian researchers found a greater reduction in pain and overall fibromyalgia symptoms in women who soaked in the mineral water. “Data aggregated from multiple research studies demonstrated that balneotherapy for 20 to 30 minutes in the evening helped improve sleep in patients with fibromyalgia,” says Dr. Iversen.
Mineral baths are known to improve psoriasis, easing inflammation and breaking down keratin, a protein that builds up on the skin’s surface in psoriasis. When Italian researchers reviewed the few studies of mineral baths to treat psoriatic arthritis, they found significant improvements in joint and spine symptoms as well as the skin.
How to Give Yourself a Mineral Bath at Home
Many people don’t have the money or mobility to venture to a far-off spa. There aren’t formal studies of home mineral baths, but you can experiment for yourself and see if you notice an effect on your arthritis symptoms.
Don’t stop your regular arthritis medication or other treatments. All of the studies showing a benefit used balneotherapy in addition to standard treatment, not as a substitute.
1. Add Epsom salt. Add about 2 cups of Epsom salt to your bath, pouring it under the faucet to help it dissolve as the tub fills. If you have a whirlpool bath, check with the manufacturer about whether mineral water is safe for the mechanisms.
2. Don’t let the water get too hot. Keep it warm and comfortable, and don’t go higher than a few degrees above body temperature. “People with decreased sensation due to nerve damage, etc., should be very cautious with hot baths as they can inadvertently burn themselves,” says Dr. Iversen.
3. Soak for 20 to 30 minutes. That’s the length of mineral baths in most spa studies.
4. Rinse off afterward. Epsom salt can dry the skin, and you may need to stop using it if that becomes a problem. Apply moisturizer or lotion, especially if you have psoriasis or psoriatic arthritis.
5. Dress warmly. This will make the relaxing warmth last longer and help prolong the relaxation effects.
6. Make it a routine. Studies showing benefit in spa soaks were seen after two to three weeks of daily baths.