Could an Epsom salt bath be the key to better health?

First discovered in 17th century England and now available on Amazon, Epsom salts have been used as an alternative treatment for countless conditions for centuries. But how—and if—these crystalized pieces of magnesium sulfate really work is still a mystery. Though many rave about the relief Epsom salts provide for everything ranging from migraines to intestinal inflammation, little scientific evidence backs up these claims.

Still, there are no reported downsides to soaking in an Epsom salt bath and the potential (if unfounded) benefits far outweigh the risks. And they have one proven medical benefit if you ingest them. Here's what you need to know.

What are Epsom salts?

Epsom salt, also known as bath salt or magnesium sulfate, is a chemical compound made up of magnesium, sulfur, and oxygen. It looks like regular salt but offers the potential health benefits of magnesium, a mineral that facilitates muscle and nerve functions. It’s typically thrown in a bath for relaxation and relief from tense or sore muscles, though it can also be ingested to alleviate constipation. Popular bath brands include Kismet, Therapy, and Dr Teal's. Some Epsom salts are enhanced with extra ingredients such as essential oils for scent, coconut milk powder to moisturize the skin, and dried flower buds for aesthetic purposes. But if you're getting it to take orally, you'll want to make sure you're getting pure Epsom salt without anything in it.

What are the benefits of soaking in an Epsom salt bath?

The most common perceived benefit of adding Epsom salts to your bath is that it soothes sore muscles and helps relieve migraines or headaches by relaxing head and neck muscles. Studies have shown that magnesium supplements can boost athletic performance, and some believe Epsom salt baths may be able to deliver similar results by boosting magnesium levels and facilitating muscle recovery.

Epsom salt baths may help alleviate stress and promote sleep, too. Magnesium helps regulate melatonin and reduce stress, but the act of taking a warm bath as part of a bedtime routine can work wonders for your sleep schedule (especially if it’s screen-free).

“I tend to recommend [Epsom salts} to people almost as a mechanism to get them in the warm bath,” says Sanjiv Lakhia, DO. “And whether or not the Epsom salts clinically add value is still probably debatable scientifically, but it’s certainly harmless," adding that the observed benefits are “outpacing” the research behind topical magnesium, but given the low cost and reported benefits, there is virtually no downside to using Epsom salts.

What are the benefits of ingesting Epsom salt?

Despite all the topical claims, the only FDA-approved proven benefit for Epsom salt is ingesting it to relieve constipation. Magnesium is a known laxative and ingesting Epsom salt draws water to the bowel, which stretches the intestines and helps move things along. The Epsom salts should work their magic within 30 minutes to six hours, and can act as a laxative for those suffering from occasional or regular constipation.

How do I use Epsom salts?

For a bath, you only need to soak in Epsom salt for 15 minutes to feel its effect, according to Cleveland Clinic. Different brands may recommend using different amounts of Epsom salt, but the concept is the same. Draw a warm-to-hot bath, throw some Epsom salt in the tub, and settle in for a while.

When using Epsom salt as a laxative, first buy Epsom salt meant for drinking so you aren’t ingesting any other ingredients. Follow the instructions on the label, which may recommend anywhere from two to six teaspoons for adults and children 12 years and older. Then dissolve the Epsom salt in water and drink. However, if you use Epsom salt for two days in a row and don’t get any relief, you should stop using it and consult with your doctor to find an alternative method.