In the UK, a significant proportion of the population are vitamin D deficient by the end of the winter, as there is simply not enough sunlight. So I would personally recommend vitamin D supplements at least.
I've always had a varied diet but have taken a multi-vitamin every day for the past 3 years and can definitely say I feel much healthier than I used to. Length and severity of colds has decreased dramatically.
I also take Rosehip extract for my Carpel tunnel syndrome. (Rosehip has also been studied and has proven to be an effective anti-inflammitory)
I also used to take Acai berry extract capsules but that became too expensive (but which were great for my, er, libido!)