16 Disturbing Things Your Nails Reveal About Your Health

2. Yellow Nails

Yellow nails are often caused by frequent application of nail polish, which causes the nail to become discolored over time, or by a fungal infection. Diseases that may cause yellow nails are those responsible for thyroid inflammation, as well as liver disease and respiratory diseases like tuberculosis and sinusitis.

Some medications, such as mepacrine (an anti-malarial drug), may also cause yellow discoloration. If yellow nails are present alongside lower leg swelling and respiratory symptoms, it could be a disease called yellow nail syndrome, but this is very rare.