I totally understand your question Whyspers!
I was worried too, so I actually went to my pharmacy and spoke to the pharmacist NOT the clerk and detailed all the info for him.

Apparently, some of my supplements do overlap, but they are vit C and some others that are considered water soluble and the excess is excreted. BUT there are some that you can take to much of and those need to be checked.

Also, I was advised that you should not take vitimins and minerals together as the minerals prevent the asorbtion of the vitamins. So I take all the vitamins with the oils at breakfast, and the minerals and chromimun, hair and nails, L-Carnitine, Qu10, etc through out the day with a space of at least one hour in between.
And vitimins in the morning or you will be kept awake with energy at night.

The only thing I was told was dangerous it mixing real natural plant herbs. This needs to be checked by a professional and in conjunction with any REAL medications you may take. I do not take any REAL medicine, but my supplements are now at 11 different things and a total of 18 pills a day!!

My supplements (taken everyday) that are considered an arsenal of weponry is as follows:
Multi-vitamin
Extra Vitamin C
Extra Magnesuim + B complex
Extra Calcium
Table spoon of Flaxseed oil (toliet and up my fat)
Fiber sachet (mainly psylum husks for the toliet)
Chromium
L-Carnitine
Oil of Oregano
Omega 3 oil capsules (Salmon Fish oils for cholesteral)
And recently added a hair and nail supplement

and hoping to add Relacore.