Common causes of yellow toenails include excessive nail polish use and fungal infections. However, yellow toenails can sometimes be a sign of a more serious underlying health condition, such as diabetes.
Nails are typically translucent, with the pinkish flesh underneath clearly visible. However, it is possible for the toenails to turn a shade of yellow. This can happen for several different reasons.
In this article, we look at why toenails might turn yellow and explain how to prevent and treat this symptom.
Nails primarily consist of a hardened protein called keratin. The same protein also occurs in the hair and skin. Nails comprise multiple parts, including:
- nail plate — the hard, outer shell
- nail bed — the flesh underneath the nail plate
- nail folds — the skin around the nail plate
- cuticle — the skin tissue covering the base of the nail that protects newly forming keratin
- lunula — the light-colored semicircle at the base of the nail
Toenails grow as the living cells under the cuticle replicate and push older, dead cells forward. These dead cells form the hardened nail plate that protects the toe.
Part of the toenail turning yellow can be a natural consequence of aging. Changes to the color, thickness, and shape of toenails can occur as a person gets older and should not be cause for concern.
However, yellow toenails can also occur for other reasons, some of which may require treatment. These include:
Infection
If toenails come into contact with a harmful fungus, this can lead to a fungal nail infection called onychomycosis.
Onychomycosis can affect any part of the toenail and may cause it to appear yellow. The infection can also be uncomfortable and make it difficult for a person to walk.
Fungal infections are a common cause of yellow toenails.
Yellow nail syndrome
Yellow nail syndrome is a very rare condition that can cause both fingernails and toenails to turn yellow. The nails may also grow more slowly, lack a cuticle, and damage easily.
Yellow nail syndrome also has more severe symptoms, including respiratory problems and swelling of the lower limbs. The cause of the condition is unknown, but it is more common in people aged over 50.
Nail polish
Excessive use of nail polish can cause toenails to become discolored. In particular, using red, yellow, or orange nail polish can cause the toenails to appear yellow.
Although they may look unpleasant, yellow toenails resulting from too much nail polish are harmless.
Underlying medical conditions
Yellow toenails can develop in some people as a symptom of an underlying medical condition, such as:
- psoriasis
- tuberculosis
- thyroid conditions
- diabetes
- sinusitis
- jaundice
In people with these conditions, it is very likely that other symptoms will also occur alongside yellow toenails.
Unless the suspected cause is excessive nail polish use, a person with yellow toenails should consider seeing a doctor as they may need a prescription to treat the condition.
This is especially important for people experiencing other symptoms alongside their yellow toenails. These symptoms may include:
- pain
- bleeding
- changes to the shape or thickness of the nail plate
- swelling
For most people, the cause of yellow toenails will be fungal infection or overuse of nail polish. In the case of excessive nail polish use, ceasing to use nail polish for at least a week should allow the nail to return to normal.
Fungal infections are straightforward to treat using an oral or topical antifungal medication. Treatment periods for these infections can be lengthy, with some courses of medication lasting up to a year.
For people with an underlying condition, treating the cause of yellow toenails is the most effective way to deal with the problem.
However, several home remedies may help with yellow toenails. These include:
- mixing tea tree oil with a carrier oil and applying it to the affected nail
- soaking the affected nail in hot water mixed with baking soda
- applying vinegar to the affected nail
- including a sufficient amount of vitamin E in the diet
- soaking the affected nail in a mixture of hydrogen peroxide and hot water
It is not always possible to prevent yellow toenails from occurring. However, people can reduce their risk of this symptom by:
- washing the toenails regularly, applying soap or shower gel directly to the feet when showering
- keeping the toenails dry, taking care to dry them properly after washing
- using clean nail clippers
- wearing clean shoes that fit properly and do not put pressure on the toes
- avoiding wearing closed-top shoes all day, particularly in hotter climates
- avoiding swimming in contaminated or dirty water
- wearing clean socks
- airing out sports shoes after use
- exercising regularly to stimulate blood circulation
There are several possible causes of yellow toenails. For most people, the cause will be either fungal infection or overuse of nail polish. However, for some people, it could be a sign of a more serious underlying condition.
Unless the cause is excessive nail polish use, people with yellow nails should speak to a doctor. Practicing good foot hygiene, keeping the toes clean, and treating any underlying conditions may help to prevent yellow toenails.