The lines on your palms may or may not reveal your future, but if you turn your hands over and look at your fingernails, you might be able to tell a lot about your health.
Fingernails and health: Indicators of systemic disease
As long ago as the 5th century, the Greek physician Hippocrates learned that fingernails and health were closely related, and the state of a person’s nails could give lots of clues to hidden systemic disease.
A systemic disease is a health disorder that affects a whole system of operations in the body. Systemic disease may therefore cause damage to multiple organs.
For example, diabetes is a disease of the endocrine, nervous, and metabolic systems. Unchecked, progressive, or advanced diabetes can cause severe damage to the kidneys, eyes, skin, blood vessels, etc.
What are fingernails made of
Fingernails (and toenails) are made up of mainly two layers.
The first layer is the fleshy, top side of your fingertips, called the nail bed. This is packed with nerve endings and blood vessels.
Shielding the soft nail bed is the second layer. This is the hard, shiny covering called the nail plate.
How do fingernails grow
At the base of the nail plate is the lunula, a slice of white that looks like a crescent moon. The lunula may not always be visible, or may appear on just one or two out of all the fingernails. It is usually most prominent on the thumbnail.
Just below the lunula, underneath the skin, is a section of active tissue called the germinal matrix or nail matrix.
The nail matrix produces keratin cells that are continually pushed upward and outward, densely packing together to form the hard nail plate. With every new row of cells, the keratin sheet moves along the length of the nail bed and extends past to form the nail tip.
Fun fact:
Keratin is the same material that makes up hair, and is also present in large quantities in the mix of cells that make up skin. Keratin is also what makes up animal hooves and bird beaks!
What do a healthy person’s fingernails look like
People in good health would have fingernails and toenails that are shiny, smooth, and hard, with a nice pink or mauve color.
The nail tips would be white, and strong yet flexible. That is, they will bend slightly when pressed, but not crack or split.
How to examine fingernails for health symptoms
Sometimes, nails may be in such obviously bad shape that a glance is enough to let you know things inside your body may not be okay. But even if your nails appear fine, you may want to dive a bit deeper.
Sit in a comfortable chair in a well-lit spot, and examine your nails through a clean magnifying glass. Keep a notepad handy to write down or draw what you see.
Alternatively, take a photo of your nails with a smartphone or digital camera and zoom in to get a better look.
Spot an illness just by looking at your fingernails
Unhealthy nails are not always a sign of systemic disease. Sometimes, it could be because of a localized problem like fungal infection, that may be cured with proper treatment.
But if your fingernails are otherwise alright and fungus-free, possible underlying health conditions may be revealed from discoloration, damage, poor texture, poor strength, and changed shape.
- Discolored nails
One of the most glaring symptoms of poor health is nail color. Pale nails, yellow nails, or blue nails are all symptomatic of underlying health problems.
Pale nail beds: Nail beds get their tone from the mass of blood vessels bundled at the fingertips. Pink or purplish nail beds mean your heart is pumping blood well enough to reach the extremities.
Light colored, or almost white, nail beds are a sign of poor blood circulation. This may be because your heart isn’t working at full capacity, or there are blockages in your veins.
Light or white nail beds could also be a sign of anemia, liver disease, or kidney damage.
Yellow nails: Nail tips often turn yellow from activities like cooking, washing dishes, and gardening. Or they may just be stained from a dark nail polish.
Trim the tips and examine new growth. If nails continue to grow out yellow, it may be indicative of thyroid disorders, autoimmune diseases like psoriasis, or lung disorders such as emphysema.
Blue nails: Cyanosis, or a bluish tinge to fingernails, is a sign of low oxygen in the blood. This could be because of poor blood circulation, congestive heart failure (CHF), chronic obstructive pulmonary disease (COPD), or pneumonia.
Terry’s nails: Terry’s nails are characterized by a mostly white, glassy-looking nail bed and a narrow band of pink or reddish-brown just below the nail tip.
The condition is named after Dr. Richard Terry, who noticed that many of his patients diagnosed with cirrhosis of the liver had the same or similar appearance to their fingernails.
- Damaged nails
Nail damage shows up as cracks, splits, and layers peeling off the surface of the nail plate. This kind of damage may happen because of contact with harsh chemicals, but it could also be a sign of poor nutrition, anemia, and hypothyroidism or low thyroid function.
- Ridges and nail pitting
Lightly feel the surface of a nail by running the pad of a fingertip over it. Do you feel vertical ridges on the nail plate? These raised lines could be symptomatic of rheumatoid arthritis.
Look closely at the nail plate. Do you see pitting, like tiny pinpricks dotting the surface of your nails? Nail pitting could hint at a weakened immune system, psoriatic arthritis, or cirrhosis of the liver.
- Thickened nails
Hard nails with a reasonable thickness are a sign of good health, but nails that are too thick could mean diabetes, especially if they also appear dry and brittle.
People with diabetes are at particular risk of developing thickened toenails since blood flow to the lower legs may be compromised, or the person may have developed tissue damage such as gangrene.
- Clubbed nails
The natural ‘shape’ of your nails is determined by the interplay of the nail bed and the underlying nail matrix. This shape can be round, square, elongated, broad, narrow, or a combination of these.
Clubbing is a very gradual process that can change the natural shape of your nails. It starts with a swelling or puffing up of the fingertips and nail beds. You will notice the fingernails curling down at tips. Instead of appearing to grow out from the base of the nail bed, the nails will look detached, as if they were caps placed on the fingertip.
Clubbed fingernails are often a sign of hypoxemia, or chronically low levels of oxygen in the blood. Hypoxemia is usually caused by lung diseases like asthma or pulmonary edema, sleep apnea, or any kind of cardiovascular disorder that prevents the heart from properly oxygenating blood.
What nails say about health
Changes to nail shape, structure, and color are a normal part of aging, but keeping an eye out for sudden abnormalities may help you uncover chronic health problems you may not have been aware of.
Should your fingernails start looking or feeling different, let your doctor know at the earliest. This will enable you to take proactive action toward managing your health better.