What Causes Ridges in Fingernails?

Ridges in the fingernails are actually normal, and can simply be a sign that you have a vitamin b-12 deficiency. Vertical ridges, or ridges that run from the start of your fingernail, straight to the end, are normal. Horizontal ridges however, ones that run sideways along your fingernail, can be a sign of organ trouble of failure, and you should talk to your doctor about them