they don't look great and i'm wondering if it's some kind of vitamin deficiency? i've also heard it could be linked to an allergy like hay fever but for the first time in ages - he's had a succession of colds etc - ( his nose isn't running at the moment, so i'm not sure that's the reason. he has a good diet though doesn't like red meat. the dark circles have appeared in the last few days. any shared experiences?