16 Disturbing Things Your Nails Reveal About Your Health

12. Rippled or Ridged Nails

Vertical nail ridges are common and generally become more apparent with age. Horizontal ridges, called Beau’s lines, happen when something interrupts nail growth, such as trauma or injury, damage caused by acrylic or gel nails, severe illness with fever, or a reaction to chemotherapy.

In some cases, a zinc deficiency can cause horizontal nail ridges. Often, the ridges are not noticeable until long after the initial cause has disappeared. This is because fingernails take four to six months to grow out fully, and toenails take six to 12 months.