Fungal nail infections - also known as onychomycosis - are a common condition that can affect anyone. They occur when fungi invade the nail, causing thickening, discolouration and brittleness. But what causes these infections, and why do some people seem more prone to them than others?

Fungi and the Nail Environment

Fungal nail infections are caused by microscopic fungi that thrive in warm, moist environments. The most common culprits are dermatophytes, a group of fungi that feed on keratin - the protein that makes up your nails. Yeasts and moulds can also cause infections, but dermatophytes are the primary cause.

These fungi are found everywhere, including on the skin, in shoes and in communal areas like swimming pools and gyms. While they are harmless in most cases, they can invade the nail if given the right conditions.

Fungal Nail Types

Common Causes of Fungal Nail Infections

Poor Foot Hygiene

Not washing and drying your feet properly can create the perfect environment for fungal growth. Moisture trapped between the toes or under the nails encourages fungi to multiply.

Wearing Tight or Non-Breathable Shoes

Shoes that are too tight or made from synthetic materials can trap heat and moisture, creating ideal conditions for fungi to thrive. If your feet sweat excessively and don’t have a chance to dry out, the risk of infection increases.

Walking Barefoot in Communal Areas

Public places like swimming pools, gyms, and changing rooms are breeding grounds for fungi. Walking barefoot in these areas increases the risk of picking up an infection.

Nail Trauma

Injuries to the nail, such as stubbing your toe or wearing ill-fitting shoes that press against the nail, can weaken the nail’s protective barrier. This makes it easier for fungi to enter and establish an infection.

Pre-existing Conditions

Certain medical conditions, such as diabetes, poor circulation and weakened immune systems, can make individuals more susceptible to fungal infections. These conditions reduce the body's ability to fight off infections, allowing fungi to take hold more easily.

Ageing

Older adults are more prone to fungal nail infections due to slower nail growth, reduced blood circulation, and years of exposure to potential fungal sources. As nails thicken and become more brittle with age - they are also more susceptible to infection.

Previous Fungal Infections

If you've had athlete’s foot, the same fungi can spread to the nails if left untreated. Fungal skin infections, particularly between the toes, are a common precursor to nail infections.

Causes of Fungal Nail

Can Fungal Nail Infections Be Prevented?

While fungal nail infections are common, but there are steps you can take to reduce your risk:

  • Keep your feet clean and dry, paying special attention to the spaces between your toes.
  • Wear breathable socks and change them daily, especially if they become damp.
  • Choose well-ventilated shoes and avoid tight-fitting footwear.
  • Use antifungal powders or sprays if you are prone to sweaty feet.
  • Avoid walking barefoot in communal areas – wear flip-flops or shower shoes instead.
  • Keep your nails trimmed and filed to prevent cracks where fungi can enter.
  • Disinfect nail clippers and avoid sharing them with others.

When to See a Podiatrist

If you suspect you have a fungal nail infection, it's best to seek professional advice. While mild cases can sometimes be managed with over-the-counter antifungal treatments, more severe infections often require prescription medications or specialist treatments. A podiatrist can assess the condition of your nails and recommend the most effective treatment plan.

Fungal nail infections don’t go away on their own, and if left untreated, they can worsen over time. If you notice persistent discolouration, thickening, or brittleness in your nails, it’s worth getting them checked to prevent further complications.

Understanding the causes of fungal nail infections is the first step in preventing and treating them effectively. By maintaining good foot hygiene and being mindful of risk factors, you can keep your nails healthy and free from infection.