Other cursory information, I can't find proof for this, if anyone knows, please cite. When you take Vit D, you can not take mega doses of Vit D 'only'. Being an oil soluble vitamin, you have to use almost all oil soluble vitamins along with it to be able to keep all oil soluble vitamins in good levels. So I would also supplement Vit A (preferably palmitate form) and mixed tocopherols (not dl-form /synthetic form of Vit E).
Unlike vitamin B complex I think it is OK to take single large dose of vitamin D, especially the natural D3, alone. I am thinking that you can get a large single 20-25,000 iu of vitamin D3 just by being at the beach for a day. (Not really since we would probably be using sunscreen at the beach but you get the idea).
They say that taking vitamin A with vit D, such as cod liver oil, can hamper absorption of both vitamins but I take it anyway but always monitor my blood levels of D.
There are some studies out showing that vitamin E can actually hurt your health. But I suspect that is because there are eight different forms of natural vitamin E but most supplements contain only the D-alpha-tocopherol
. Too much of the alpha can hinder absorption of other forms especially the D-gamma-Tocopherol
form of vitamin E.
So that is why you should take mixed tocopherols of E, but that may not be necessary for vitamin D since there is only one natural form of vit D, and that is vit. D3.