Vitamin & Mineral supplements are an interesting subject.

For Calcium, you can take it, and it may not do you any good, at all.

Our metabolism is WAY complicated, and there are about 20 steps that
may be needed to make
the calcium you're ingesting, into calcium that your body can use. How
many steps are needed
depends on what exact kind of calcium we are taking in.

Each step along the way, you body has to have the building blocks
(enzymes, etc), to take that
calcium to the next step.

So just taking in Calcium may not do you any good at all, or it may
give you just what you need -- IF
your body can supply the several little steps to transform it, along
the way. Otherwise, it is worthless.

An easy answer to that problem, is to take your calcium (whatever),
along with a meal which includes
"complete protein", like non-fat milk, meat, etc. You don't need much
of it.

A recent large study found that taking Vitamin/Mineral supplements
regularly, was actually
shortening people's life spans. Hello!

Study's author's suggested the culprit was too much vitamin B iirc,
but more study is needed to be sure.

I still take my vitamin/mineral supplement, but only once or twice
each week. I always
try to take it with a meal which includes "complete" protein.

There is NO doubt whatsoever, that the pill pushers have oversold us
on the value of these
vitamin/mineral supplements, for most of us, in a first world
country.

Diet supplements are MUCH worse though - a total disgrace.