Epsom Salt Baths: The Science Behind Them

Your muscles are achy and soaking in a hot bath sounds so soothing. My grandmother would have suggested adding Epsom salt to my bath. Epsom salt always seemed like some mysterious white coarse powder and I never clearly understood how it was supposed to help. Is there some magic to this ritual or is there actual science behind why people have used it for so many years?

Epsom salt is made up of magnesium sulfate. Magnesium is an important electrolyte in our body and it is required for effective nerve conduction and muscle contraction. Magnesium helps strengthen bones by playing a role in calcium regulation. It is believed to be involved in sugar metabolism and insulin release assisting in the prevention of diabetes and contributes to the control of blood pressure reducing strokes and heart attacks. The majority of magnesium is stored in our bones, cells and organs but the body maintains a small level, about 1%, in our blood at constant levels. Our body does not make magnesium, so we must either get it from either the food we eat or supplement it in our diet.

What does Epsom salt do?

According to the Epsom Salt Council, soaking in Epsom salt helps replace the magnesium that is lost through a variety of conditions or as a result of medications. Magnesium loss may occur from dietary reasons either from eating foods that suppress absorption such as a high fat diet or from bowel conditions that contribute to excess loss like diarrhea. Certain antibiotics or diuretic medications create a magnesium deficiency and excess alcohol use may lead to a need for supplementation.

Stress is thought to reduce the levels of magnesium by lowering its availability to bind serotonin which contributes to relaxation and mood elevation. . Some medical research has shown magnesium plays a role in reducing inflammation, a possible contributor to muscle pain, so soaking in an Epsom salt bath might do double duty both soothing muscles and replacing the lost electrolyte.

Sulfates are difficult to replace with food but are easily absorbed through the skin during the bath. Sulfates are important in formation of brain tissue and joint tissue. It is believed that sulfates help create digestive enzymes that are used to detoxify residual medicine in the body.

How does Magnesium Sulfate get absorbed by the skin?

A study was done by Dr. R.H. Warring at the School of Bioscience in Birmingham, England to report on the absorption of magnesium sulfate across the skin. Blood samples were drawn prior to baths and 2 hours after the first and last bath for 7 days. All but 2 of the 19 people tested had a rise in magnesium and sulfate levels in their blood. The longer people soaked in Epsom salt, the higher the blood concentration rose. Those who did not have magnesium levels increased in their blood did show an elevation of magnesium levels in their urine indicating that there had been some temporary retention of magnesium through their skin and tissues and it was now being excreted.

How to use Epsom salt:

1. Baths-Sprinkle 2 cups of Epsom salt to your bath water and soak for at least 10-15 minutes.

2. Compresses- Put 2 cups of Epsom salt in a warm gallon of water. Soak a towel in the mixture and place on the part of the body needing attention. Leave on for 10-15 minutes

Precautions:

1. Epsom salt can be used as an oral laxative for occasional constipation, but never use Epsom salt in an enema. Fatal outcomes have occurred to both children and adults from excess absorption of magnesium through the intestine. If taken orally, follow the directions closely to prevent excess oral intake as well.

2. Before using Epsom salt, you should check with your doctor to make sure that there is not a medical reason to avoid it, especially if you are pregnant.

3. It is also important to check with your doctor or pharmacist if you are on prescription medications especially cardiac and blood pressure meds which affect the loss and absorption of magnesium.

It is uncertain whether soaking in Epsom salt will replenish enough lost magnesium to make a chemical difference in our body's balance. There are no studies directly testing the health benefits of Epsom salts but since the body is capable of absorbing magnesium through the skin and our muscles often feel better after soaking in a hot bath, combining the two might be a way to improve our muscle recovery after all.

http://ods.od.nih.gov/factsheets/magnesium.asp

http://www.epsomsaltcouncil.org/

http://www.epsomsaltcouncil.org/articles/Report_on_Absorption_of_magnesium_sulfate.pdf

http://ods.od.nih.gov/factsheets/magnesium.asp