Taking an Epsom salt bath alleviates soreness and softens skin by restoring healthy levels of magnesium and sulfate ions in the body. Epsom salts are composed of magnesium sulfate, which dissolves to release ionic magnesium and sulfate ions once introduced to water. These ions can be absorbed through the skin and help alleviate a number of conditions, from eczema to tired muscles.
Magnesium plays an important role in many bodily functions, including the release of specific enzymes and the contraction of muscles. According to the Epsom Salt Council, many Americans are deficient in magnesium, and this explains why so many experience relief of muscle soreness after soaking in Epsom salts. By soaking from 12 to 15 minutes three times per week, the body receives the magnesium needed to function normally and even to contribute to overall health. Sulfate, the other ionic species found in Epsom salts, plays a role in forming joint proteins, which eases joint pain in patients with arthritis and other joint-related conditions.
Epsom salt baths are generally prepared by adding 1 to 2 cups of Epsom salts to a bathtub of warm water. Tepid water is better than excessively hot water because it does not strip away the skin's natural oils.