With aging, nails become dry and brittle and flat or concave instead of convex. They may develop ridges along their length. Nail color may change to yellow or gray. Brittle nails may split.
Toenails require special attention in older people and in people with diabetes (see Foot problems in diabetes) or peripheral vascular disease (see Foot care). Such people may have poor sensation in their feet, which increases the risk of injury when they try to trim their nails. A foot doctor (podiatrist) can help care for their nails to prevent skin breakdown that can lead to infections.