Epsom Salts for Fibromyalgia and Chronic Fatigue Syndrome

Do Epsom-Salt Baths Work?

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Do Epsom-salt baths ease the pains of fibromyalgia and chronic fatigue syndrome? They're a common home remedy, but do Epsom salts really do anything? And if so, how?

Epsom salts aren't really "salt." They're crystals of magnesium sulfate. They've been used as a home remedy for hundreds of years.

Like many people with these conditions, I take Epsom-salt baths frequently and I believe these soaks are more effective than a hot bath by itself.

However, that's not something we can prove or quantitatively measure on our own. It's not hard to find skeptics who believe any improvement is due to the placebo effect.

At the same time, you can find claims online about all kinds of things that Epsom salts can supposedly do. Some people say that they ease all types of pain as well as speed healing. You can also read that topical magnesium sulfate (applied to and absorbed through the skin) it's more effective than magnesium supplements.

If you start digging into it, though, there's not much science behind these claims. In fact, Epsom salts and other forms of topical magnesium sulfate have barely been researched at all.

What Do We Know?

Ingested magnesium is important for several bodily functions. We know that it is involved with:

  • Your body's energy production in the form of adenosine triphosphate;
  • Formation of cells;
  • Maintenance of muscles, bones and nerves;
  • Relieving muscle tenderness;
  • Possibly reducing the specific types of pain and tenderness of fibromyalgia (some of which are shared by chronic fatigue syndrome.)

On the flip side, magnesium can also be really hard on the digestive system.  It can cause nausea, persistent diarrhea, bloating and cramping, and many of us can't tolerate it as a supplement.

Epsom salts themselves are sometimes dissolved in liquid and drunk as a laxative.

Lots of Questions

All of those benefits are linked to magnesium in your diet or taken as a supplement. When you make the jump from ingested to topical use, though, a couple of questions arise:

  1. Is magnesium absorbed through the skin, and if so, does enough get through to make a difference?
  2. Does it have the same benefits as ingested magnesium?

We do have a limited amount of evidence about #1. Most things are not absorbed through the skin, which is waterproof. However, a small (unpublished) 2006 study by Rosemary Waring did show that 12-minute Epsom salt baths did raise the blood and urine levels of both magnesium and sulfate by a small amount. 

Is it enough to make a difference? That depends on a lot of factors, and right now we just can't answer that question definitively. Because it does get into the bloodstream, there's no reason to believe it works differently from ingested magnesium. And absorbing it this way may bypass the unpleasant digestive side effects.

Unsupported Claims

Some online claims about Epsom salts' benefits are completely unsupported or even contradicted by science.

A common one is that it "detoxes" your muscles through "osmosis." Remember me mentioning that skin is waterproof? That automatically rules out osmosis, because that process by definition means movement of water through a membrane. Particles dissolved in water may well be able to pass through skin, but water does not.

And detoxification? Your body already takes care of that. The term "detox" has become a buzzword that few people really understand. For more information on that, see The 3 Best 'Detox' Diets for Weight Loss, by Verywell.com Weight Loss Expert Malia Frey.

So ... Where Do We Stand?

Those of us with fibromyalgia and chronic fatigue syndrome know all too well that science still has a lot to learn. Some of my most effective treatments are unproven, even uninvestigated, by researchers, while some of the well-researched treatments I've tried have been utter failures, setting me back instead of making me better. Still, when unproven claims abound, it pays to be skeptical.

Because Epsom salts have been popular for a long time, we know they're not dangerous. However, if you expect miracles based on unfounded claims, you're likely to be disappointed. If Epsom salt baths work for you, great! Just don't expect dramatic improvements or a cure.

Of course, few treatments are without possible side effects. To see what to watch for with Epsom salts as well as how to get started, see How Often Can Epsom Salts be Used? by Verywell.com Healthy Aging Expert Mark Stibich, PhD.

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