Why are my toenails so thick?

Thickened toenails are a very common problem that podiatrists see in clinic. Many patients notice that their nails have gradually become harder to cut, more yellow in colour, or thicker than they used to be.

While thick nails are often harmless, they can sometimes cause discomfort in shoes or become difficult to manage at home.

There are several reasons why toenails may become thickened. Understanding the cause can help determine the best way to manage the problem and prevent it from worsening.

What Does a Normal Toenail Look Like?

Healthy toenails are usually smooth, slightly curved, and relatively thin. They appear pink because of the blood supply beneath the nail and grow slowly over time. On average, toenails grow around 1–2 millimetres per month.

A normal nail should be easy to trim using standard nail clippers and should not cause discomfort when wearing shoes. When nails become thickened, they may look more opaque, yellow, or uneven and can sometimes feel hard or brittle when cutting.

Common Causes of Thickened Toenails

Fungal Nail Infection

One of the most common causes of thickened nails is a fungal infection, known medically as onychomycosis. This occurs when fungi infect the nail and the skin underneath it.

Fungal nail infections can cause nails to become:

• Thick and difficult to cut

• Yellow, white, or brown in colour

• Brittle or crumbly at the edges

• Slightly lifted away from the nail bed

These infections often develop slowly and may affect one or several nails. Fungal nail infection follows infection of the skin known as tinea pedis (athletes foot). So read our blog here about preventing fungal skin infection in order to minimise your chance of getting a fungal nail infection.

Interestingly around 50% of suspected fungal nail infections are actually just thickened nails due to injury or repeated trauma. We can test the nail in clinic to determine if any fungal infection is present.

Thickened nail due to fungal infection

Repeated Trauma or Pressure

Repeated pressure on the toes can cause nails to gradually thicken over time. This is common in people who wear tight footwear or participate in sports that involve frequent impact on the toes.

Runners, hikers, and footballers often develop thicker nails due to repeated minor trauma to the nail over many years. Even everyday footwear that is slightly too tight can contribute to this problem.

Ageing

As we get older, nails often grow more slowly and may naturally become thicker. This is partly due to reduced circulation and the accumulation of small injuries to the nail over time.

Many older adults notice their nails becoming more difficult to trim, which is a very common reason for visiting a podiatrist.

Thickened toenails

Skin and Nail Conditions

Certain skin conditions can affect the nails and lead to thickening or changes in appearance. These include conditions such as psoriasis. When this happens, nails may appear thickened, ridged, or distorted.

Previous Nail Injury

A past injury to the nail or nail root (known as the nail matrix) can cause permanent changes in the way the nail grows. If the nail matrix is damaged due to stubbing your toe or dropping something on the nail for example, the nail may grow back thicker or misshapen.

Even injuries that occurred many years ago can affect nail growth long term.

When Should You See a Podiatrist?

While thick nails are common, it is a good idea to seek professional advice if you notice:

• Nails becoming painful or uncomfortable in shoes

• Nails that are very thick or difficult to cut

• Significant colour changes in the nail

• Debris building up underneath the nail

• Nails that are becoming distorted or ingrown

A podiatrist can assess the nail, determine the likely cause, and recommend appropriate treatment or care.

How a Podiatrist Can Help

Podiatrists regularly treat thickened nails and can make them much easier to manage.

Treatment may include:

• Professional nail trimming and thinning

• Reducing the thickness of the nail safely

• Advice on footwear and foot care

• Testing for possible fungal infection

• Recommending treatment options if required

Regular podiatry care can also help prevent thick nails from causing pain, pressure, or further problems.

Can Thick Nails Be Prevented?

While not all thick nails can be prevented, there are steps you can take to reduce the risk:

• Wear well-fitting shoes with enough room in the toe box

• Wear protective footwear for sports and other activities where nails could get injured

• Trim nails regularly and straight across

• Keep feet clean and dry

• Change socks daily

• Treat athlete’s foot promptly if it develops

Taking care of your feet can help maintain healthier nails and reduce the likelihood of thickening.

Final Thoughts

Thick toenails are very common and can develop for a variety of reasons, including fungal infection, repeated pressure, ageing, or past injury. Although they are often harmless, they can sometimes cause discomfort or become difficult to manage at home.

If your nails are becoming thick, painful, or difficult to cut, a podiatrist can help assess the cause and provide safe, effective treatment to keep your feet comfortable.

If you are concerned about thickened nails we are happy to help. Call 0161 427 4937 or email info@mrpodiatrist.co.uk to schedule a consultation