Why do my nails look funny?
What are nails?
Nails are a bit like little claws. They are made of a tough protein called keratin (as is hair, horns and hooves). A nail consists of the nail plate (the bit you can see), the nail matrix (where the nail grows from), and the nail bed underneath. Nails start to develop in the womb. Fingernails start to develop in the embryo at 10 weeks and toe nails at 14 weeks. They are completely developed by 32 to 36 weeks. In young children, the nails are thin and flexible. In older people they can often get thicker and stiffer.
Why do we have nails?
The nails protect the ends of the fingers and toes (also known as digits), help with precise movements (by supporting the soft part of the digits), and are handy for gripping things (think of picking up something very small), scratching and scraping.
Causes of funny looking nails
Nails can look abnormal for a variety of reasons:
- Fungal nail infections. Nail fungus can cause discolouration (usually white or yellow) on the surface or underneath the nail. Sometimes part of the nail can separate from where it attaches to the toe underneath. The technical name for this is onycholysis. Eventually the nail can thicken and become flakey. Read more about fungal nail infections here.
- Lines and ridges. These are common and are usually normal. They may worsen during pregnancy. A large groove down the centre of the nail can be caused by a habit of repeatedly rubbing or scratching the nail (a bit like the habit of picking the nails). A horizontal ridge across the nail (also known as a Beau's line) may form as a result of an illness, infection or previous chemotherapy.
- Senile nails. As you age, the nails may become thickened, brittle and develop ridges and separation of the nail layers at the end of the nail. This is not a disease, but is one of the signs of ageing, although not all people develop such nails as they get older.
- Whitish or yellowish nails. These can occur due to onycholysis in the absence of fungal nail infection, although persistent onycholysis can make the nails more susceptible to fungal infection, as the separated part of the nail is a good place for fungi to get underneath the nail.
- Red or black nails are usually due to a haematoma, or blood under the nail, which occur from trauma such as kicking or dropping something on the nail. The discoloured area will grow out with the nail and be trimmed off as you trim your nails. If you have a black spot under your nail that was not caused by trauma, you may want to see a health professional to check that it is not due to a skin cancer. A simple biopsy can help to determine the cause.
- Green or other coloured nails. These can be caused by a bacterial infection (the green type is usually caused by a bacterium called Pseudomonas aeruginosa), which grow under a nail that has partially separated from the nail bed.
- Pitted nails. These may be associated with psoriasis or other skin problems that affect the nail matrix, the area under the skin just behind the nail.
- Swelling and redness of the skin around the nail is called paronychia. This is an infection of the skin at the bottom of the nail (cuticle). Sometimes this happens quite quickly, and is usually caused by an infection. If it happens over a longer period of time, it may be caused by chronic irritation of the nail, and this may lead to an infection too, as the nail and skin around it is more susceptible to infection if it is irritated over time.
- Chronic nail trauma occurs from ill-fitting shoes and work boots, or sports which involve repeatedly starting and stopping, kicking, and long distance running. This trauma can cause permanent damage to the nail and matrix, which can mimic the appearance of fungal nails.
What should I do if my nails don't look right?
See your Podiatrist or GP, who can help to work out why your nails don't look right, and suggest possible treatment options for you.