Generally speaking, if the color or texture of the nail changes, it’s a sign of unhealthy nails. But these characteristics may alter for various reasons.
“Unhealthy nails have unusual colors,” says Colombo, explaining that a yellowish, bluish, or greenish hue is out of character for nails. Essentially, anything besides the pinkish base is a sign that something’s not right.
Jaliman notes that sometimes a white or yellow chalky material might sit underneath the nail plate, which is the sign of a fungal infection, also known as onychomycosis. Jaliman explains that this debris materializes when fungus breaks down the keratin in the nail. The American Academy of Family Physicians estimates that onychomycosis happens in about 10 percent of people but may be more common in older adults.
Discoloration may also be a sign of melanoma, a serious type of skin cancer. According to the American Academy of Dermatology, a brown or black band around the nail or even a darker hue around the outside of the nail could be a sign of melanoma. This dark streak might be accompanied by a bump underneath the nail.
Onychoschizia, more commonly known as nail splitting, refers to soft, brittle, thin nails, per the American Osteopathic College of Dermatology (AOCD). “A brittle nail feels rough, breaks easily, and is not smooth at the distal ends,” Colombo explains.
Colombo says brittle nails can be attributed to many things, including fungal or bacterial infections, inflammatory conditions such as lichen planus or psoriasis, nutritional or vitamin deficiencies, hypothyroidism, or simply aging. But per the AOCD, onychoschizia is typically due to fingernails being too wet too often (cleaning or working with water all day) or overly dry.
Splitting down the center of the nail plate could also be a sign of melanoma or another concerning growth, as outlined by the AAD.
A nail that is too hard may suggest previous nail trauma, psoriasis, or a fungal infection, says Colombo; a nail that’s too soft can’t function efficiently either. Nails are often softened by chemicals that are common in household products such as cleaning supplies, laundry detergents, and even nail polish remover, per the AOCD.
If your nails do become soft, you may notice them start to peel layer by layer. This once again is likely due to external traumas such as harsh chemicals, exposure to too little or too much moisture (excessive hand-washing or wet hand activities), overbuffing the nails, too many gel or acrylic manicures, or picking off nail polish with fingernails instead of polish remover, Colombo says.
Separation From the Nail Bed
Onycholysis is a condition where the nail plate separates from the nail bed. According to the Mayo Clinic, common potential causes may include infection, injury, negative side effects from drugs or personal-care products, or even symptoms of conditions like psoriasis or thyroid disease.
The AAD also notes that a nail separating from the nail bed could also be a sign of melanoma or other concerning growth.
A healthy nail has a smooth surface. When it starts to develop rough ridges, that’s when you know something’s up, Jaliman says. If the ridges run from the top of the nail plate to the bottom, it’s likely a natural sign of aging, Colombo points out. But if they run from side to side, something else might be at play.
“Nail ridges can be a sign of vitamin deficiencies or diabetes,” Jaliman says. “For example, iron deficiency anemia can cause nail ridges.” If one of these underlying concerns is the issue, once you treat it, the nails will return to their healthy, smooth, shiny state.
These can look like little pinpricks in the surface of the nail. “Nail pitting can be caused by psoriasis or eczema,” Jaliman says. “When these conditions are treated, the pits will resolve.”