The nails are a dermatologist’s dream to see inside some of the body’s ailments. Unhealthy looking nails may be able to tell you about a bigger issue with your overall health.
Here are the five top warning signs to look out for with regard to nail health.
1. A white half-moon at the base of your nail
The technical term for this is lunula, and “a normal lunula or moon shape is small, just peeking out from your cuticle,” Marmur explains. If you have a little bit of white poking out, it’s not at all cause for concern. In healthy nails, “they are a whitish color and take up a small portion of the bottom of your nail,” explains Carielle Nikkel, a registered dietician and nutritionist.
However, if the white portion of the nail grows and begins to take over half of your nail or more, then it becomes a different story. “This is called Terry’s nails, [and it’s] an indication of systemic illnesses from liver disease to heart failure,” says Marmur.
2. Brittle, weak nails
As with many things pertaining to health, this could be caused by a variety of different things — ranging from feelings of stress, over-consumption of alcohol, general aging, and vitamin deficiencies. It is most often seen, however, “in patients with poor nutrition,” Goldenberg says.
Some of the most common vitamin deficiencies that can contribute to brittle, weak nails include B vitamins (including biotin), vitamin D, and iron. “Brittle, weak, and dry nails are often caused by iron deficiency,” Nikkel says. “While a leading sign of iron deficiency is fatigue, it can also manifest through brittle or spoon-shaped nails.”
3. Black or brown streaks
Out of all of the abnormal nail signs to keep an eye out for, this is perhaps the most important. “The number one nail-health emergency is a brown stripe that starts on your cuticle,” Marmur says.
This is called melanonychia, which is technically defined as a black or brown pigmented streak on the nail bed, Goldenberg explains. In most cases it is benign, however, in some circumstances, it can actually be a sign of melanoma, the most lethal form of skin cancer, “which can be dangerous or even life-threatening, since it is a cancerous lesion,” Goldenberg explains.
4. Horizontal ridges
Horizontal rows of raised ridges on the nail itself — not the underlying nail bed — can be caused by trauma to the nail itself, Marmur explains, but they can also be a sign of something more serious.
Aside from physical trauma to the nailbed (such as slamming your finger in the car door, for example), horizontal ridges “can also indicate malnutrition, psoriasis, or a thyroid problem,” Marmur explains. “Check with your doctor if you see horizontal ridges on your nails; they may indicate a more serious problem.”
5. A red-colored infection
“The nail and fingertip are a closed compartment, so if it gets too swollen or infected, it can cut off circulation,” Marmur explains. If you find that your nails or a singular nail is red, swollen, and infected, Marmur recommends heading to the emergency room right away.
Finally …
“The skin is your body’s largest and most visible organ, always giving clues about your health,” Marmur explains. “When your skin is unhealthy, your nail matrix is compromised and forms an unhealthy nail. Conversely, when you take good care of your body, your skin and nails will be healthier.”
If you notice any changes to your nail bed or nails, don’t get stuck down a scary internet rabbit hole. Instead, visit a board-certified dermatologist who can rule out more serious health conditions and advise on best practices for the future.