Causes of toenail discoloration and remedies

Toenails are usually semi-transparent, but they can sometimes become discolored, turning purple, black, green, or yellow, depending on the cause.

Several health conditions and other factors can cause toenail discoloration. Some require no treatment, but others may signal a serious condition that needs treatment from a doctor.

In this article, we look at the common causes of toenail discoloration. We also discuss treatment options and when to get advice from a doctor.

 

The health and appearance of the feet and toes can provide insight into someone’s overall health.

Conditions that may cause toenail discoloration include:

Nail fungus

Nail fungus is a common infection that is not usuallyTrusted Source painful unless it is severe. The medical term for nail fungus is onychomycosis, and it causes about 50% of nail diseases.

Nail fungus affects toenails more often than fingernails, with the infection typically developing on the big toe first.

Toenail fungus can often begin as a skin infection called athlete’s foot. It can also occur when other yeasts or molds get into the nail through cracks or breaks in the skin or nail.

Nail fungus affects up to 14% of people in North America. A study published in PLOS Pathogens found that toenail fungal infections are more likely to affect:

• older people — the prevalence is 18.2% in people aged 60–79 years compared with 0.7% in people younger than 19 years
• males than females, though the reasons for this difference are unclear
• people with poor peripheral circulation
• those who walk barefoot in shared bathrooms or locker rooms

 

 

 

Psoriasis

Psoriasis is a disorder that causes the body to make skin cells more quickly than they break down, which results in a patchy buildup on different parts of the skin.

According to the American Academy of Dermatology Association (AAD), people with psoriasis often develop nail psoriasis at some point in their lives, causing the nails to:

• change color
• get thicker
• lift off the nail bed
• crumble
• develop dents

 

 

Injury

Injuries can cause toenail discoloration. A red area will appear that turns purple over time and then brown or black. People may notice this after they stub their toes, wear tight shoes when running, or do anything else that causes small blood vessels to break and leak blood under the toenail.

Diabetes

People with diabetes are more vulnerable to fungal infections than the general population, so toenail discoloration can be a warning sign of the condition or a complication in someone with a confirmed diagnosis.

Poor circulation and reduced sensation in the feet often accompany diabetes. Due to this, people may injure their feet without being aware, creating opportunities for nail fungi to invade and flourish.

 

Melanoma

Melanoma is a severe form of skin cancer that can appear as a dark stripe running lengthwise down the toenail.

Learn more about melanoma here.

Yellow nail syndrome

Yellow nail syndrome is a rare disorder that can cause yellow toenails, breathing problems, and swelling in the legs.

 

 

Nail polish

Nail polish can also cause toenail discoloration if the polish penetrates deep into the keratin layers in the nail. The discolored nail eventually grows out, although it can take time.

Other causes

Illnesses affecting other parts of the body, such as lung disease, diabetes, and liver disease, can sometimes cause changes in nail color.

However, as the AAD point out, noticing such changes does not necessarily mean that an individual has a serious condition. Still, it could indicate that a visit to the doctor is in order.