Fair enough, I'll change the description to include something about naturally occurring elements in the body. Out of curiosity, would there be enough lithium present in your body from lithium treatments that it would be more abundant than the rest of these elements? A single gold tooth would almost definitely be enough to make the list, but I wonder about the lithium.
I did some searching, looks like there is usually about 25g of magnesium in a normal adult human body. The usual dosage of lithium is 1800mg. I don't know how fast your body would metabolize lithium, but I doubt the it would ever build up to as high as 25g. Also, a gold tooth only weighs a few grams, so you would need to have a fair number of them to outweigh the magnesium in your body. Thanks for the interesting search topic!