Do we need to inhest metals? Some yes, the following metals we cannot love without:
sodium
potassium
magnesium
calcium
Iron
manganese
cobalt
copper
zinc
molybdenum
What metals are in vaccines
aluminium in the form of salts like you might find in antacids, dental cement or baking powder
this makes the vaccine work better , because its been found to make the body build a stronger immunity against the virus its innoculating against. I can find some more detailed explanations if you are interested. there are studies being done to see if calcium could replace it i believe.
ethyl Mercury which has a half life of less than a week, and the dose is roughly the same as eating 1 can of tuna, but its the less toxic form than you find in tuna
Its a preservative that why it's in there. There are Mercury free vaccines for some things that you can get now. but I'm not sure off the top of my head what preservative (if any) they have replaced it with