magnesium supplements will only be helpful if you don't have enough magnesium in your body or your food. If you already do have enough in your food a supplement won't help. If I take a magnesium supplement I get terrible diarrhoea!
As for the bath, there isn't much science to back up the claims of epson salts baths, so from that point of view you would be better off taking a supplement than bathing in it. You might like to read about it:
Thank you for reminding me about the Epson Salts and magnesium & also others who have mentioned it in the past about it being a good source of getting some magnesium. I usually take magnesium tablets but are out of them and as I have a bath & also some Epsom Salts intend to try it. I have not tried the 2 together yet so don’t know if you need some magnesium supplements while having Epson Salts I look forward to hearing from someone who has tried both when their magnesium levels are low.
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