Nail ridges can be vertical or horizontal depressions on the nail plate. Vertical ridges are usually harmless and a sign of aging, but they can also be caused by decreased circulation to fingertips, stripping nails with solvents during manicures, tumors, and certain dermatological conditions. On the other hand, horizontal ridges are usually a sign of a health condition or nutrient deficiency. Some of the common causes of horizontal ridges include:

• Beaus lines: These are horizontal ridges or dents in your nails that may happen when something interrupts your nail growth, such as an injury or illness.
• Malnutrition: Certain nutritional deficiencies, such as zinc deficiency or iron deficiency, can cause changes to your nails, including horizontal ridges.
• Serious nail injury: A serious nail injury can cause horizontal ridges in your nails.

If you have nail ridges, it is important to determine the underlying cause. Your healthcare provider can help you determine why you have ridges in your nails and recommend appropriate treatment. In some cases, treating the underlying cause can help you grow smoother nails. Additionally, avoiding exposure to chemicals and excessive water, as well as using hand sanitizers in moderation, can help prevent dry, brittle nails and the resulting ridges.