|MadSci Network: Medicine|
The nails are a good way for a doctor to assess overall health. For example, people with protein deficiency will have very small white "moons" in their nails, indicating that the nails are growing slowly. In general, it is best to have your fingers examined by a physician and/or a dermatologist, who can properly diagnose a disease or deficiency, if there is one.
That being said, there is a condition called koilonychia, which is depicted on the Shands Website here: http://www.shands.org/he alth/imagepages/2008.htm. As it states in the website, if your nails look like this, you could possibly have an iron deficiency (which a blood test would be able to confirm or discredit).
Another possibility is that the horizontal bumps and ridges represent Beau's lines. These are associated with infection, drug treatments (chemotherapy and other medications), trauma or systemic disease. Some instances of these are at the Johns Hopkins (via dermatlas.org) website here: http://dermatlas.med.jhmi.edu/derm/result.cfm? Diagnosis=218. The lines often grow out after the disease has passed, chemotherapy has stopped or the trauma ends.
I hope this helps. Again, if you have any questions about your nail health, I would visit your primary care physician and/or a dermatologist and raise your concerns with them, as they can examine you and properly assign a diagnosis along with your full medical history.
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