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Studies show that vertical lines on your fingernails are often the result of natural aging after the age of 30 or 40, when cell renewal slows down. Dryness or small bumps can also cause lines on your fingernails, making you feel embarrassed when people look at your hands.
But sudden, deep vertical lines on your fingernails can indicate more.
The natural aging process,
dehydration or dry skin, or
genetics playing a role.
2. Horizontal lines on your fingernails (Beau’s lines)
Imagine a teacher named Sarah suddenly seeing deep horizontal grooves appear on her nails. These lines on your fingernails, called Beau’s lines, indicate that nail growth has stopped for a short time.
Research from the Cleveland Clinic links horizontal stripes on your fingernails to high fever, serious illness, or significant stress that occurred weeks earlier. The surprise of new horizontal stripes on your fingernails can cause panic about recent health problems you thought were behind you.
The next type of stripes on your fingernails goes even deeper.
3. Deep grooves or multiple lines on your fingernails.
An office worker named Maria noticed that multiple deep grooves and cracks were forming on several nails at the same time. These lines on your fingernails often indicate that the body has gone through a difficult period involving a nutrient deficiency or persistent stress.
The Mayo Clinic notes that a protein deficiency or digestive problems can cause visible, deep lines on your fingernails. The constant reminder of those lines on your fingernails, every time you type or cook, can undermine your self-confidence and make simple tasks frustrating.