A manicure is not the only reason to stop and take a good look at your fingernails. Since they can provide important clues about your health, keep an eye out for these symptoms.

1. Indentations

Dents or grooves that run horizontally across your nails are likely Beau's lines. While this usually may be the result of some kind of injury or trauma, it has also been associated with uncontrolled diabetes, zinc deficiency, and health conditions that involve a high fever.

If the indentations occur along with discoloring and loosening of the nail, you may have something known as psoriasis. A dermatologist can help diagnose the common skin condition. In addition, patients diagnosed with cancer may also experience this symptom as a side effect of chemotherapy.

2. Dark lines

"Dark brown or black vertical lines on the nail bed should never be ignored," Shilpi Agarwal, M.D., a Los Angeles-based physician told Shape. "These can be a hallmark sign of melanoma, which requires early detection and treatment."

Definitely see a dermatologist if you notice any such lines, especially if they occur only on one nail. This warning sign is more likely to occur in African-Americans and Asians according to experts.

3. Spoon nails

Concave nail growth, which gives the appearance of spoon-shaped nails, is referred to as koilonychia. More often than not, this suggests that you are suffering from iron deficiency anemia.

This is very likely if accompanied by other signs such as constant fatigue or pale-colored skin and nails, typically caused by the lack of hemoglobin in the red blood cells.

4. Yellow discoloring

Yellow-colored nails are considered a sign of aging. But if accompanied by an unpleasant odor and peeling, you may be experiencing a fungal infection. While there is medication to treat it, you may take simple steps to prevent the infection.

"Tea tree oil, diluted with Vitamin E or grapeseed oil, which is always good for your nails, will prevent help prevent fungus in the first place," advised Danielle Candido, a nail expert from Gelish.

If you frequent the nail salon, yellowing nails could also be a sign of overusing acrylic nails. A smoking habit, which can lead to nicotine staining the nails, is another preventable cause.

5. Gnawed nails

Of course, it is evident that this is caused by a nail-biting habit. But if your nails are excessively gnawed and you notice that the surrounding skin is also being chewed off, you may be experiencing elevated anxiety.

It is also among the habits associated with obsessive-compulsive disorder. "Sometimes psychiatric medicine is required to treat OCD-related nail-biting," said Debra Jaliman, M.D., a dermatologist based in New York City. "A bitter-tasting compound that's polished onto the nails can help, too."