WHFoods: What are nightshades and in which foods are they found?
Until Steve's post, I'd never heard of nightshade outside of 'Deadly Nightshade'.
There seems to be quite a lot of noise about nightshades and arthritis, though whether there is much to back that up, I've no idea.
Avoiding them would seem to be cutting out a substantial amount of really tasty foods that are packed with nutrients. Personally, I'd have to have a really good reason for that.