I wouldnt recommend drinking loads of OJ or taking multi-vits. A reasonably balanced diet will give you plenty of VitC. If I were you I'd concentrate more on water, leafy veg, brocolli, whole grain bread or rice. Getting enough water will give you more energy (oddly) and generally make you feel "better" as will getting enough fibre. I generally avoid milk it cloggs me up in my lungs and I generally feel a bit off in the guts when I eat too much of it.