Remember that vitamin A is in the form of beta-carotene in plant sources and so needs to be *converted* into vitamin A. This process is inhibited in some people (I haven't found out *why* yet) so animal sources may be preferred.Here's a link about Vitamin A.
I use Rice Chex for breading and instead of bread crumbs for things sometimes. It's fortified with vitamins and, although it might not be much, it's still something (my opinion
When making poultry of any kind, use the giblets (kidney, heart and liver) to make broth for gravy and then chop them into tiny pieces to "hide" in the stuffing (make sure that the bile sac is removed from the liver or else it gets really gross). If you have a meat grinder, grind up liver to "sneak" into ground meat dishes (meatloaf, meat balls etc)- this works best if you're making something with a sauce. I also add grated carrots to my ground meat dishes as a "filler". I make a lot of tomato-based dishes.
We rely on a D3 supplement. Even when we were eating fortified foods (read: dairy), our vitamin D was *way* too low (we don't eat fish often at all- I was raised inland and fish was kind of a delicacy). I'm not sure if it's derived from fish though. The one by Thorne- 5,000 IU- says it's "vegetarian" (not that that means anything.. I'd probably contact the company or ask your ND to find out for you). I also have a 10,000IU one which my ND orders for me (only available to health care professionals)- again no clear idea of the source.
If you check out WHFoods list of Omega-3 sources
(very bottom of page), you may be pleasantly surprised as to what foods do have omega 3s.
It has a lot of spices (cloves, oregano, mustard seed), leafy greens, cauliflower and squashes....
If you're worried about cavities, I would look at mineral deficiencies rather than vitamins. You might be benefited by trying to wrap your head around the current detox craze that has hit this forum.
Do you ever eat beets? If you do, does your pee go pink? If it does, the first thing you should consider is increasing your zinc intake (and maybe eating some fermented foods daily- many of the ladies here use Bubbie's rather than making their own sauerkraut). This will help your body to produce more stomach acid, which will allow you to digest your food better and therefor absorb more nutrients from it.
Hope that's some help.
And welcome to the forum!