I think its very useful if you use quality forms - MgMalate, MgGlycinate, MgTaurinate. You can also use MgChloride in 1/2L of water if titrated slowly over weeks. Been looking into hemp hearts as well, might experiment with those as they are very high in Mg. Most people are deficient, glyphosate for example depletes Mg in our food. Epsom salt baths are another great way to absorb Mg through the skin.