Can a Bar of Soap in Bed Cure Restless Legs Syndrome?

Can you really cure leg cramps or a sleep disorder such as restless legs syndrome (RLS) by placing a bar of soap in your bed? What was once an old wives' tale is being discussed on television programs like the "Dr. Oz Show" and in online forums.

This article explores the evidence behind this home remedy and whether it is something that can actually help you sleep better.

Possible Causes of Restless Legs Syndrome

Verywell / Laura Porter

RLS vs. Leg Cramps

First, it's important to understand the difference between these two sleep-disrupting conditions. RLS is an uncomfortable urge to move your legs that occurs most often when you're lying down at night. It happens when you're awake.

If you move, it often goes away. This is especially true if you get up and walk around. RLS may be caused by a lack of the mineral iron in your body. Other medical conditions can also cause the problem.

Leg cramps are different. They're sudden, painful spasms in your feet or legs. The cramps may ease up in a few seconds, but the pain can last much longer. Leg cramps have different causes. They can usually be relieved by stretching the muscles. They can increase as you get older.

Causes

Researchers don't fully understand what causes these two conditions. There is some evidence that low iron sparks RLS symptoms. It may also be due to problems with a brain chemical called dopamine. Dopamine helps to control the way your body moves.

Sometimes there's a problem in the nervous system. RLS has been linked to a condition called peripheral neuropathy, which is damage to the nerves throughout your body. It's also associated with multiple sclerosis and Parkinson’s disease. These two health conditions affect your body's ability to move.

RLS can also be a problem during pregnancy. There's some evidence that, in pregnancy, RLS may be linked to lower amounts of the minerals magnesium and zinc.

Leg cramps can happen if you're low on electrolytes like calcium, magnesium, and potassium. Electrolytes are minerals that are needed for various body functions, particularly nerve and muscle function.

If you're dehydrated or you've over-exerted yourself physically, you may be running low on electrolytes. That could bring on a bout of leg cramps.

You may also experience leg cramps if you have diabetes, liver disease, or kidney failure that requires dialysis. Dialysis is a treatment to help remove toxins from your body when your kidneys aren't working properly.

Soap as a Possible Treatment

Television programs like "Dr. Oz" and "The Doctors" have discussed the use of soap to relieve these conditions. It is a popular topic in discussion forums and comment threads.

Advocates say that something in the soap—magnesium, lavender, or even electrically charged ions—seeps into the skin and alters your body chemistry. Magnesium and lavender are popular additions to sleep aids, but there is no evidence that a bar of soap in the bed will help relax your legs.

Some say you should place the bar of soap at the foot of the bed. Others say it must be close to the location of the cramps. Under the sheet and inside a sock are two other suggestions. It isn't clear how soap in such different locations could have the same effect on the legs.

This treatment may be supported by traditional beliefs or anecdotal evidence, but there is little scientific research to back up the claim. In a small study involving 105 people with severe RLS, massage with lavender essential oil relieved RLS symptoms better than foot massage on its own. It's important to note that the lavender oil was massaged into the skin, not placed nearby.

There is no logical reason to place a bar of soap in the bed to treat either restless legs or leg cramps.

What Evidence Is Needed

The gold standard for scientific research is a randomized controlled trial. For example, researchers would test two similar groups with restless legs or leg cramps. Half the subjects would use a bar of soap and the other half would use a placebo. A placebo is basically a fake treatment. In this case, half the group might use a soap-shaped piece of plastic.

Then, the outcomes would be compared. Researchers would find out about each group's symptoms. Ideally, the subjects and the researchers would be blinded, not knowing who used soap or the placebo.

No such studies have been done to test this practice. It isn't likely that researchers would be able to find funding for such a study because there's so little science behind the idea.

Summary

It's been said that tucking a bar of soap under your sheets could help relieve the pain of leg cramps or the discomfort of restless legs syndrome.

There is no scientific evidence to support this home remedy. If you're dealing with either of these health conditions, it's a good idea to identify the cause so you can find an effective treatment.

A Word From Verywell

There is probably no harm in placing soap in your bed. It's not likely to bring you any relief, though. If your symptoms don't go away, speak with your healthcare provider or a sleep specialist about science-backed treatment options to help you rest.

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5 Sources
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  5. Ghasemi M, Rejeh N, Bahrami T, Heravi-Karimooi M, Tadrisi SD, Vaismoradi M. Aromatherapy massage vs. foot reflexology on the severity of restless legs syndrome in female patients undergoing hemodialysis. Geriatrics (Basel). 2021;6(4):99. doi: 10.3390/geriatrics6040099.