Epsom salt was once the most popular medical drug in England. Its beneficial antiseptic and restorative qualities were not understood, but users knew that it was good for health and promoted a long life.
As well as preventing sclerosis, kidney diseases and rheumatism, Epsom salt was also useful in avoiding weight gain.
Chemically, Epsom salt is known as 'magnesium sulphate'. This is not found naturally, so it has to be made from a suitable substance containing magnesium.
The best substance is dolomite, an abundant rock found in the mountainous Dolomites region in Italy. Dolomite belongs to a large group of neutral substances known as 'salts' (formed by an alkaline base combining with an acid radical).
Dolomite is a double salt known as 'calcium magnesium carbonate'. The rock consists of two metals (calcium and magnesium) combined with two non-metallic elements (carbon and oxygen).
Epsom salt is also a 'salt', but its constituents are magnesium, oxygen and sulphur (another non-metallic element). This is unlike dolomite, which is a carbon salt consisting of magnesium, oxygen and carbon.
In the manufacturing process, the carbon ingredient in the magnesium carbonate (dolomite) is replaced by sulphur. This then forms magnesium sulphate (Epsom salt).
However, the magnesium prefers carbon to sulphur. So, Epsom salt readily exchanges its sulphur for carbon whenever possible. The magnesium draws out carbon, making the now inert residue soluble and facilitating excretion.
Epsom salt's strong affinity for carbon and carbon compounds is the secret of its value for medical purposes. It is always trying to revert to its original carbon state, which is why it's useful in helping to treat bodily conditions.
So, how does it work? Carbon, in one form or another, is one of the main building blocks of vegetation. This in turn provides the food on which we survive. The human body then excretes its waste products in the form of carbon.
Most of this carbon waste passes out via the lungs or bronchial tubes as carbon dioxide, which is formed as the result of a combustion process called oxidation. The blood and tissues need enough oxygen to carry out this process, in order to get rid of the carbon waste.
If there's not enough oxygen, 'retarded combustion' happens. This is when partially oxidised forms of carbon waste (such as uric acid) and other acids and toxins form.
These partially oxidised carbon compounds tend to build up in the blood and tissues, which can cause ill health and disease. However, Epsom salt can absorb and negate this harmful waste, acting as a useful remedial agent when correctly used.
Magnesium sulphate (Epsom salt) paste is still widely recommended by doctors to help draw out impurities and poisons from the body. It is most beneficial when applied externally, because of its ability to draw waste (stored in the tissues) from the body through the skin.
However, when taken internally in small doses, Epsom salt also acts on the kidneys. By increasing their action, they can get rid of more waste matter solution.This information is taken and adapted from the booklet 'Epsom salt: its value and use' (1953) by Dr H Valentine Knaggs.