You may not look very often at your fingernails, but did you know that your fingernails can tell you a lot about your health? Did you know there are hundreds of medical conditions and diseases that may cause nail changes? Your nails can show the history of recent health and physiological problems, and has been used as a diagnostic tool since ancient times.

Sometimes it might be a fungal infection or injury, but your fingernails can sometimes indicate a more serious underlying problem, such as problem in the liver, lungs or heart.

The Half Moons at the Base of your Nails

When the nails are healthy, they have a pink color and the moons near the nail base are light pink to white color. According to Dr. L Reed, ND, the half moons at the base of your fingernail is an indicator of good thyroid health. Each nail that is missing a half moon indicates a weaker thyroid. Weak thyroid can lead to mood swings, depression, thinning hair as well as other symptoms.

The Nail Texture

Healthy nails are smooth, without ridges, grooves, spots or discoloration. But what happens if you see that your nails have changed in color, shape, texture, thickness or any other unusual growth pattern, and you don’t know the reason for that? Well, maybe it’s time to visit your GP.

Here you will learn how to read the signs on your nails and discover the secrets they tell you about your overall health:

1. Brittle or crumbly nails

Brittle or crumbly nail can be a result of aging or a long exposure to detergents or nail polish, but sometimes it can indicate a fungal nail infection, Lichen planus (a condition that forms an itchy rash on the skin or in the mouth), thyroid disease or psoriasis. In rare cases it can also may be an indication of a Reactive arthritis which is a painful form of inflammatory arthritis.

2. Discolored nails

Yellow nails can occur due to a long use of nail varnish, but can indicate fungal nail infection or psoriasis. It can also indicate several other ailments, such as: jaundice due to liver problem (also see my other post about early signs of liver damage), sinus infection, a problem with the thyroid gland, lung infection and lymphedema (fluid retention that generally occurs in arms or legs). For more information, read my article about the most common causes of yellow nails.

Green-black nails – indicate bacterial infection that usually occurs under loose nails.

Bluish or purple fingernail beds may indicate oxygen deprivation.

Grey nails – can be caused by certain medications.

Brown nails – can indicate a thyroid disease or malnutrition. Fingernails that are half white at the bottom and half brown near the tips can be a sign of kidney failure, AIDS or appear after chemotherapy.

White nails – might be a sign of aging, fungal nail infection or iron deficiency (anemia), as well as other range of ailments, such as: cirrhosis (scarring of the liver), kidney or heart failure, diabetes, hyperthyroidism, malnutrition or after chemotherapy.

3. Thickened nails

There are a few reasons for having thick nails but they are commonly caused a fungal nail infection, but can also result from psoriasis and reactive arthritis (a painful form of inflammatory arthritis). Yellowish, thickened, slow-growing nails can also indicate lung diseases.

4. Loose nails

When the fingernails become loose and can separate from the nail bed, it may indicate an injury or infection, as well as thyroid disease, psoriasis, poor circulation or allergic reaction to medicine.

5. Spoon-shaped nails (koilonychia)

When your finger nails curve inwards and look scooped out, it may indicate iron-deficiency (anemia), hemachromatosis (liver condition which results in iron overlaod), Raynaud’s disease (that affects the blood supply to the fingers and toes), heart disease and hypothyroidism.

6. Pitting or dents on the nails

Pitting or small dents on your nails can indicate psoriasis, eczema, reactive arthritis, and alopecia areata (hair loss due to autoimmune disease).

7. Grooves across the fingernails (Beau’s lines)

If you notice deep lines or grooves that run across the nail, it might be a result of having chemotherapy, a previous injury, exposure to cold temperatures, Raynaud’s disease that affects the blood supply to the fingers and toes, diabetes, vascular disease, zinc deficiency and illnesses associated with a high fever.

8. Nail clubbing

This is when the fingertips and nails are unusually curved around the fingertips. It can be harmless due to increased blood flow to the fingertips, and can run in families, but if it suddenly occurs, it may indicate low oxygen level in the blood that can indicate lung disease, as well as other ailments such as heart disease, inflammatory bowel disease (IBD), liver disease and AIDS.

9. White lines running across the nails

In this case the lines run parallel to the base of the fingernail. Don’t confuse it with white spots or streaks that are normal, but when there are parallel white lines across the nails, it’s a sign of low levels of protein in the blood, which can be due to malnutrition or liver disease.

10. Dark stripes running down the nails

This is common among black people and in most cases it’s normal. However sometimes it may indicate a skin cancer that affects the nail bed, called subungual melanoma. Generally, this type of cancer only affects one nail.

11. Red or brown little streaks under the nails

These are usually lines of blood caused by tiny damaged blood vessels and are called splinter hemorrhages. This is nothing to worry about, but if many nails are affected, it may indicate another underlying disease.

Don’t ignore your fingernails and the health signs they indicate. Have a closer look at you nails more often to keep an eye on your health. Your nails and your overall health are closely related and offer you a window into your health.