I have been looking for vitamin/mineral supplements, which I need because of malabsorption after chemoradiation.
I can find the recommended daily value, but often the contents of a tablet are described only as, for instance, 'zinc picolinate', 'magnesium citrate' etc. How do I find out what percentage if these tablets is elemental zinc, elemental magnesium and the like? Is there a good site which gives an overview?
Thank you!

I am not sure but I know that you most likely want better quality probably pharmeucutical quality. Store brands contain additives and so forth. The amount should be listed on the bottle as something like zinc picolinate 99mcg or magnesium citrate 250 mg.

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Thanks, I'll have a look!