Brittle or crumbly nails
Brittle nails are often just a sign of ageing or long-term exposure to water or chemicals such as detergents and nail polish. Nails can be protected by wearing gloves for all wet work and by frequently applying moisturising cream to the nails.
Sometimes, brittle or crumbly nails can be caused by:
- a fungal nail infection, which can be cleared by taking a course of antifungal tablets (this especially tends to be the cause for crumbly toenails)
- a skin condition called lichen planus, which can just affect the nails
- an underactive thyroid or overactive thyroid, where the thyroid gland either doesn't produce enough hormones or produces too many
- nail psoriasis, a long-term skin condition that can cause the nails to become crumbly
Discoloured nails
Yellow nails can also result from any of the following:
- frequent application of nail varnish
- lymphoedema, a long-term condition that causes swelling of the skin
- permanent damage to your airways caused by bronchiectasis (a long-term lung condition)
- sinusitis (inflammation of the lining of the sinuses)
- inflammation of the thyroid gland, found in the neck
- tuberculosis (TB), a bacterial infection affecting the lungs
- jaundice (yellowing of the skin) due to liver disease
- some drugs, such as mepacrine or carotene
- chronic paronychia (infection of the nail fold)
Grey nails can be caused by medication such as antimalarials or minocycline.
Brown nails can sometimes be caused by thyroid disease, pregnancy, malnutrition and frequent use of nail varnish.
