Your nails can seem like a small detail, something you trim, file, or cover with polish. But because nails depend on steady nutrition, oxygen, and blood flow as they grow, visible changes can sometimes offer clues about what is happening elsewhere in the body.
That does not mean every spot, ridge, or color change is a reason to panic. Nails can change because of aging, injury, products, or everyday wear. Still, when a change is new, unexplained, or keeps getting worse, it may be worth bringing it up with a healthcare professional.
Naturopathic doctor Sara Norris has noted that nail growth can reflect how well the body digests and absorbs nutrients. Other doctors point out that nail appearance may also be affected by illness, circulation, skin conditions, or infection.
Nail changes that may deserve attention
Deep horizontal grooves: Beau’s lines are noticeable ridges or grooves that run across the nail. They can appear after the body goes through a major stress, such as a severe illness, infection, high fever, chemotherapy, or COVID-19. Dr. Bhavini Shah of Lloyds Pharmacy Online Doctor has explained that these lines may develop when nail growth is temporarily interrupted. In more severe cases, the nail can stop growing and shed, a condition known as onychomadesis.