A: Vertical ridges on your nails can be a normal result of aging. Horizontal ridges, on the other hand, can be caused by diseases that affect the entire body, including malnutrition, heart attack, severe infections, and metabolic disturbances, including poorly controlled diabetes. A very common cause of ridges is malnutrition or malabsorption. Vitamin deficiencies cause ridges on fingernails, as the body's production of the materials in the nail is interrupted.
More facts about ridges
A: Onychorrhexis or lamellar dystrophy, is a condition that causes horizontal splits within the nail plate. Nail splitting is often seen together with onychorrhexis – long-wise (longitudinal) splitting or ridging of the nail plate – and these 2 diseases together are called 'Brittle Nail Syndrome' Caused by the following: