Vertical stripes
Vertical ridges or longitudinal grooves are common and usually run from the cuticle to the tip. They are often age-related, as nail ridges can become more visible with age.
In some cases, they can also be an expression of a nutrient deficiency, such as a deficiency in certain minerals or vitamins (vitamin B12, magnesium or iron).
Vertical furrows are common in older people and are often harmless. However, if they appear suddenly or become more noticeable, it’s worth checking for conditions such as anemia or thyroid problems.
Horizontal stripes
Horizontal stripes or grooves, also known as beautiful lines, may indicate more specific health problems.
These horizontal indentations can occur after physical trauma to the nail or as a result of a serious illness or condition, including malnutrition, uncontrolled diabetes, heart attacks, or respiratory diseases.
The appearance of these grooves is often due to temporary disruptions in nail growth caused by periods of severe stress or illness, as the body may temporarily slow down or stop nail growth.
If the grooves “develop suddenly,” it indicates a sudden outbreak, according to the NCBI. And if they appear on all 20 nails, “it’s usually the result of a systemic disease such as mumps, pneumonia, coronary thrombosis, Kawasaki syndrome, syphilis, and hypoparathyroidism.”
White, parallel horizontal lines that do not cross the nail surface can indicate liver or kidney problems. These lines, called Muehrcke’s lines, usually disappear temporarily when the nail is pressed down and often occur on several nails at the same time.
A drop in blood protein levels, particularly albumin, can also cause these white streaks, which are common in people suffering from malnutrition or chronic liver disease.
If Muehrcke’s wrinkles are visible on several nails, consult your doctor as this may be a sign of protein deficiency or kidney/liver problems.
