A slightly yellow or green tinge in your nails may mean that you are suffering from some sort of respiratory condition. Two common examples of this are chronic bronchitis or lymphedema, the swelling of your hands. It's not only respiratory diseases that cause the nails to be discolored, however. Anything that can slow nail growth can give nails this appearance. Yellow nail syndrome can also cause the nail(s) to be lacking in cuticles and even become detached from the nail bed.