If your seriously depleting, I'd take a strong mult every day. I used to be all about the vitamins (especially B Vitamins), but I've been reading up on some of what Mike Mentzer used to talk about on dieting and supps and he's pretty much turned me a 180 from over doing vitamins. According to Mike, you know you're wasting your money when your piss is bright yellow. You're pissing out your vitamins. I'd be wary of spending too much cheese on vitamins that you'll probably just piss out.
Mike's philosophy is to get your nutrition from a balanced diet. Even when dieting, he insisted upon a balance of all foods. He ate high-carb and sugary foods all of the time when dieting or not. He stressed maintaining a calorie deficit to lose fat, but eating plenty of carbs to spare muscle and help overall well being and health. Good luck with what ever you go for, bro.