So I asked my mom (high school chemistry teacher) for any ideas she had on why bathing in Epsom salt/magnesium sulfate is supposedly so healthy.
Here is what she hypothesized:
1) Magnesium is a cofactor for a lot of enzymatic reactions in the body (including enzymes used for detoxification). It is also a component of synovial fluid.
2) Sulfate binds heavy metals more avidly than magnesium, so theoretically would exchange magnesium for a heavy metal it came in contact with. When sulfate binds a heavy metal it becomes insoluble and precipitates out of solution (which would drive the reaction further towards completion).
3) The super-saturated salt bath acts as a disinfectant (similar to honey because they are both hypertonic solutions) on open wounds by lysing bacterial cells.
Number 1 seems plausible to me since your skin can definitely absorb nutrients/chemicals, so I guess bathing in magnesium sulfate would increase the amount you have available in your body? Number 2 seems a little far-fetched, since I don't know that we really carry a lot of heavy metals in our body (any of you know about this?), and Number 3 also definitely seems likely... but I wonder if frequent baths would change your natural skin flora for the better or the worse?
Also, during her "research" she said she stumbled upon an article on the benefits of fasting combined with vigorous exercise (she is always giving me a hard time about practicing yoga on an empty stomach). Apparently this combination promotes detoxification because a lot of toxins are stored in fat cells (where they can hide out for long periods of time), but when you fast, your body is forced to metabolize fat to provide energy, thereby releasing the stored toxins to then be metabolized or excreted in your sweat. I wonder, should I be showering immediately after yoga to wash off my sweat then, otherwise these toxins will be reabsorbed through my skin if I don't?