A lot of processed foods are adding vitamins (as a marketing ploy - "our junk food is good for you,"), but healthwise it makes more sense to get the vitamins from natural sources (or take a multivitamin)than to eat cookies fortified with vitamins.
The sugar, fat, processed flour probably outweigh the benefits of the vitamins. And there's also the concern that you could overdo fat-soluble vitamins by eating too many fortified foods.
However, if you're going to eat a cookie, I suppose it doesn't hurt to eat a fortified cookie (unless you're eating tons of them or are taking mega-doses of fat-soluble vitamins).
Vitamin D is not just a vitamin, it's a hormone, so I think you'd want to make sure that your intake was within reasonable limits (though I understand vitamin D overdose is pretty difficult to do - but then again, except for dairy not many foods have ever been fortified with vitamin D).
Last edited by kaplods; 08-21-2011 at 05:55 PM.