> Magnesium? Its widely known that magnesium is used by the body lol

Who disputed this?

> What they “doubt” is that it can be absorbed through the skin

The science is helpful. Magnesium sulfate is absorbed less effectively than magnesium chloride. Of course, you're not eating the amount of Epsom salts one dumps in a bath.

> And it is studied btw - problem is there are countless on both sides

This is why meta analysis exists.

> Magnesium sulfate is absorbed less effectively

Drinking the same Epsom salt in water that you soak in has the same effect as soaking in hot or cold water with it, and it's also the same effect as taking magnesium supplements sold over the counter.

You can try it yourself - totally safe. You already eat magnesium all the time.

Whatever you're doing with your comment, I'm not convinced.