According to Costantino et al. (2020), mineral waters are among the first medications used by humans. Specifically, sulfate mineral waters are frequently used in clinical therapy. Sulfur (in the form of anion sulfate) is the predominant element in sulfate mineral waters. Different cations can also be present, such as calcium, magnesium and sodium. Sulfate mineral waters used in clinical therapy are available in different methods of administration and include drinking the water, immersion of the body in a bath, mud therapy and inhalation.
Magnesium sulfate-rich mineral water, in particular, has been popular for their beneficial effects on health. Magnesium sulfate is also known as Epsom salt. It is a compound made up of magnesium, sulfur and oxygen. The name “Epsom” is derived from the town of Epsom in Surrey, England, where it was discovered originally from their springs.
The most common use for Epsom salt is in baths; Almost all the reported benefits of Epsom salt are attributed to its magnesium content. When dissolved in water, it releases magnesium and sulfate, which ideally are absorbed through the skin. However, there is not enough data to prove that magnesium or sulfate is absorbed when put in contact to the skin through bathing.
Uses of Oral Magnesium
Magnesium is a very important macromineral in the diet of humans. It plays a lot of roles in the body, including serving as a cofactor in more than three hundred enzymatic reactions. Magnesium is essential for regulation of muscle contraction (including that of the heart), blood pressure, insulin metabolism, and is required for the synthesis of DNA, RNA, and proteins (Kirkland et al., 2018).
Oral magnesium has been studied quite extensively and is currently being used for a number of disorders. Its primary use is due to its laxative properties.
Magnesium sulfate has a long history in the treatment of constipation. It started as “fluid magnesia” used in 1829 for the first time by Sir James Murray to treat stomach pain in a patient, apparently with great success. Since the early 20th century, the pharmacological effect of magnesium sulfate on constipation has been studied (Dupont & Hébert, 2020).
A study by Ikarashi et al. in 2011 found that magnesium sulfate increases the aquaporin 3 expression level in the intestines and changes the osmotic pressure in the colon. Through these functions, oral magnesium sulfate can act as an osmotic laxative.
Drinking magnesium sulfate-rich mineral water has likewise been found to have a laxative effect. It facilitates fecal excretion by retaining water and increasing its volume in the stool (Costantino et al., 2020).
Bothe et al. (2017) also investigated whether drinking natural mineral water rich in magnesium sulfate can help improve bowel function in functional constipation. Their results showed that bowel movement frequency, as well as stool consistency, greatly improved with the natural mineral water as compared to placebo. The subjectively perceived symptoms concerning constipation, likewise, significantly improved.
Magnesium sulfate-rich mineral waters have been used for centuries for their laxative effects. Dupont & Hébert (2020) reviewed the clinical data available reporting the efficacy of magnesium sulfate-rich mineral waters for functional constipation. They concluded that magnesium sulfate water is effective and safe, and may represent a natural treatment for functional constipation.
In the nervous system, magnesium is important for optimal nerve transmission and neuromuscular coordination. It also serves to protect against excitotoxicity or the excessive excitation in the brain leading to neuronal cell death (Kirkland et al., 2018).
In 2017, Gano et al. evaluated the association between prenatal treatment with magnesium sulfate and cerebellar hemorrhage in newborns. A group of preterm newborns delivered less than 33 weeks age of gestation were identified and evaluated with 3T-magnetic resonance imaging (MRI) shortly after birth. Antenatal magnesium sulfate exposure of the newborns was verified through medical records that showed administration of the drug to their mothers prior to delivery.
Results of their study showed that magnesium sulfate exposure before birth was associated with a significantly lower risk of cerebellar hemorrhage. This could, therefore, explain some of the neuroprotective effects reported with the use of magnesium sulfate in this population (Gano et al., 2017).
Coronary Heart Disease
A meta-analysis in 2016 done by Jiang et al. reported on the beneficial effects of drinking water with high levels of magnesium sulfate. They reviewed 9 articles involving 77,821 cases of coronary heart disease. Their results showed a significant reduction in mortality from coronary heart disease among those who drank magnesium-rich water.
Epsom Salt in Baths for Babies
Magnesium nowadays is most popularly being used as Epsom salt baths. The theory behind this use is that when one soaks in an Epsom salt bath, magnesium and sulfate break down and are absorbed in the body through the skin. However, this has yet to be proven in studies. Still, just by soaking in warm water, one can relax the muscles and loosen stiff joints.
The following are instructions to make a bath of Epsom salt:
- Fill a standard sized bath tub with warm water
- Add 2 cups (475 grams) of Epsom salt
- Soak for about 15 minutes
For babies, Epsom salt bath is used as detoxification. Hot baths are known to be relaxing, however, there is currently not enough proof for the benefits of the Epsom salt bath itself.
Magnesium salts are known to have beneficial effects in inflammatory diseases. In 2005, Proksch et al. examined the efficacy of bathing in magnesium salt-rich water for atopic dermatitis. They used a bath solution containing 5% Dead Sea salt, as the Dead Sea water is known to be rich in magnesium chloride. They concluded that bathing in the magnesium salt solution improved skin barrier function, enhanced skin hydration, and reduced skin roughness and inflammation.
Magnesium has a huge role in the growth and differentiation of keratinocytes. It is responsible for helping the skin preserve water, thus acting as a natural moisturizer. Hence, magnesium can be a useful agent to treat and manage skin pathologies, such as psoriasis and atopic dermatitis (Costantino et al., 2020).
Safety of Epsom Salt Baths for Babies
Epsom salt baths are generally safe and easy to use. The risk of experiencing side effects is low because the body does not absorb that much magnesium through the skin. However, there are things to consider while using this type of bath for babies.
Babies should never be left unattended or unsupervised while taking a bath. Ensure that the Epsom salt has been fully dissolved. Pouring the salt into running water can help it dissolve faster into the bath.
Babies should be especially monitored to prevent drinking bath water with Epsom salt. While Epsom salt is generally safe, there can be side effects especially after oral consumption.
As discussed previously, magnesium does have a laxative effect. A baby who has consumed Epsom salt orally from a bath may develop diarrhea, bloating and an upset stomach.
Magnesium overdose has also been reported in some cases. Symptoms include nausea, light-headedness, headache, and flushed skin. In severe cases, overdose with magnesium can result in heart problems, coma, paralysis, and even death.
An allergic reaction is another symptom to watch out for when Epsom salt is ingested. Contact your doctor immediately if your baby accidentally drinks water from his or her Epsom salt bath.
Parent should make sure to test the temperature of the bath, and that it is not too hot, before soaking a baby in it. The water should be warm, with temperatures ideally between 92oF and 100oF.
Overusing Epsom salt can cause skin irritation and rashes. Consult your physician if your baby has any of these reactions to an Epsom salt bath. Children with medical conditions, likewise, should check first with their doctors before regularly using this bath.
Frequency of Bath
It is recommended that parents seek a physician’s guidance before starting to give their baby this type of bath. Ease your child into a routine of Epsom salt baths slowly. You can start with once a week and then slowly increase it to three times a week. However, it is best not to bathe your baby with Epsom salt beyond three times a week, and never use more than 2 cups of Epsom salt per bath.
While there are plenty of claims regarding the therapeutic capacity of Epsom salt, there are only a few studies to back them up. The health benefits provided by Epsom salt baths may come from years of anecdotal evidences rather than actual, scientific research. Although magnesium itself has been proven safe and effective for certain conditions, its medical benefits when dissolved in a bath and its absorption through the skin remain inconclusive.
Though relatively safe, it is best to check with your doctor before allowing your baby to soak in this “detox” bath. If your baby has medical conditions or has shown reactions to an Epsom salt bath, consulting your physician would still be the best course of action.