Bath Salts Benefits: What the Research Shows

Bath salts are mineral salts you dissolve in bathwater, usually Epsom salt, sea salt or Dead Sea salt, sometimes with oils or scent. This guide covers which claimed benefits have evidence behind them, which do not, and what to do with that.

We sell a lavender and chamomile bath salt, so read this with that in mind. Where the research is thin, or where our own listing says more than the sources support, this guide says so. For other ways to care for dry skin, see our bath bomb for dry skin guide.

What Are Bath Salts?

Bath salts are salts meant to be dissolved in a bath. There is no single recipe, so what you get depends on the label.

• Epsom salt: This is magnesium sulfate. The 2017 review discussed below uses the terms magnesium sulphate and Epsom salt for the same thing.
• Sea salt and Dead Sea salt: Sea salt is a common base. The 2005 skin study used a Dead Sea salt solution, which is a different mineral mix.
• Oils and scent: Our Relax Bath Salt blends Epsom and sea salt with lavender essential oil and Roman chamomile extract, which the product page says are used for aroma.

Does a Warm Bath Before Bed Help You Sleep?

Probably, and the warm water looks like the active part. A 2019 review found that bathing before bed was associated with better sleep.

• What was reviewed: A 2019 systematic review in Sleep Medicine Reviews found 17 studies that met its criteria, 13 of them with data that could be combined, on warm showers and baths before bedtime.
• What it found: A bath of 40 to 42.5 °C was associated with better self-rated sleep quality and sleep efficiency. Scheduled 1 to 2 hours before bed, even 10 minutes shortened the time to fall asleep.
• The proposed reason: The authors link the effect to the body's core temperature falling after the bath.
• The limit: The authors say more research is needed, because little has been published and the best timing and duration are unclear. The review covered warm water, not bath salts.

Can Your Skin Absorb Magnesium From Epsom Salt?

The evidence does not support it. A 2017 review concluded that transdermal magnesium is scientifically unsupported and that its authors could not yet recommend it.

• The skin barrier: The review notes that the outer skin layer is a water-repellent barrier, and that magnesium ions are not able to pass through it easily. Absorption may be possible only at sweat glands and hair follicles, which are 0.1% to 1% of the skin surface.
• The bath study: A 19-person study reported that seven daily Epsom salt baths raised blood magnesium. The review called it questionable and noted it was published on a commercial Epsom salt website, not in a peer-reviewed journal.
• The lotion trial: In a randomized trial of 34 healthy volunteers using a magnesium sulfate lotion for three days, magnesium levels did not differ from the placebo group.
• What would settle it: The authors suggest larger studies with higher doses over longer periods. The PubMed record lists the same paper.

Do Dead Sea Salt Baths Help Dry Skin?

One small study suggests they may, in people with atopic dry skin. It tested a Dead Sea salt solution on one forearm, so it does not prove a full bath helps.

• The design: In a 2005 study, volunteers with atopic dry skin soaked one forearm for 15 minutes in a 5% Dead Sea salt solution. The comparison was the other forearm in tap water.
• The result: Skin hydration rose on the salt-treated forearm in every group, and roughness and redness fell. Barrier function improved in the subgroup that had raised water loss through the skin to begin with.
• The caveats: It was a short forearm soak, not a bath, and the salt was Dead Sea salt, not the Epsom and sea salt blend in most bath salts. The authors' affiliations include a company, Mavena AG.

How Do You Take a Bath Salt Soak?

Run a comfortably warm bath, dissolve the salt, soak for 10 to 20 minutes and time it 1 to 2 hours before bed. The temperature and timing come from the sleep review; the rest is ordinary use.

1. Run the water warm. The review's range was 40 to 42.5 °C. Our product page also advises warm, not hot.
2. Add the salt. Our page says 1 cup per bath. Pour it under the tap so it dissolves fully.
3. Soak 10 to 20 minutes. The review saw effects from as little as 10 minutes. Our page suggests 20.
4. Time it before bed. The review scheduled baths 1 to 2 hours before bedtime.
5. Pat dry. Dry off gently and stop using the salt if your skin itches or stings.

What Does Our Own Relax Bath Salt Page Claim?

Our product page says magnesium sulfate is the standard soak mineral for muscular and nervous-system unwind, and that the bath turns "wired and tired" into "asleep by 10:30". We could not source those claims for this guide.

It also says you step out of the bath softer. We are reviewing that wording. Until it is backed, treat it as the seller's statement, not as evidence, and rely on the sourced points above.

When Should You Talk to a Doctor About Bath Salts or Magnesium?

Talk to a doctor if you have a skin condition, are pregnant or have a medical condition and want to take hot soaks, or if you think you are low in magnesium. This guide is information, not medical advice.

On low magnesium, the 2017 review says oral supplementation is well documented, while the skin route is not. A doctor can tell you whether that applies to you.

Frequently Asked Questions

Do bath salts have any real benefits?

A warm bath before bed has sleep evidence in a 2019 review. Claims that magnesium absorbs through the skin are unsupported, and Dead Sea salt has one small hydration study.

Does Epsom salt absorb through the skin?

A 2017 review calls transdermal magnesium scientifically unsupported. The one Epsom bath study it describes had 19 people and was not peer-reviewed.

How long should you soak in a bath?

The 2019 sleep review found that as little as 10 minutes, scheduled 1 to 2 hours before bed, shortened the time to fall asleep. Our product page suggests 20 minutes.

Are Epsom salt and bath salts the same thing?

Not always. Epsom salt is magnesium sulfate. Bath salts can be Epsom, sea salt, Dead Sea salt or a blend, sometimes with oils. Ours blends Epsom and sea salt.

Can bath salts help dry skin?

One small 2005 study found a Dead Sea salt forearm soak improved hydration in atopic dry skin. It was not shown for Epsom salt or for a full bath.

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