As a podiatrist, it’s something I get asked a lot! And the truth is, there are quite a few reasons why your nails might be looking weird so I’m going to go through a few of them for you; including some ideas for how to deal with those unique nails!
There are 4 basic reasons why nails change; microtrauma (small repetitive damage), macrotrauma (big damage), fungus and natural changes associated with ageing. There are some extra ‘red flag’ type things to look out for in a weird nail so I’ll go into these a little bit too.
Let’s start with the little guy, microtrauma. Essentially, this is when your nails get a little bit of damage or pressure on a regular basis over a prolonged period of time. Microtrauma can cause your nails to thicken or thin, split or chip, lift away from the nail bed and even change shape and colour.
Lots of things can cause microtrauma from tight or poorly fitting shoes to wearing nail polish for too long or even poor big toe function that causes the other toes to retract and ‘grip’ the ground. Usually, the trauma is so mild that you won’t even feel or see it happening until the nail changes become obvious. Good news is, if you catch it early enough and remove the cause, you can fix the problem. However, toenails are sensitive and they hold a grudge, so they may take some time to look normal again! A big toenail can take anywhere from 8-18 months to completely regrow so you need to be patient and continue to avoid whatever caused the problem in the first place.
Onto micro’s big brother, macrotrauma. Macrotrauma can cause your nail to change colour, bleed, change shape, split or completely fall off! 
This one is the one that you will DEFINITELY know about!! It’s usually associated with a painful incident of some kind. Kicking your toe (known in my house as the furniture jumping out in front of you), dropping something on it or having something penetrate the nail. The changes to your nail associated with macrotrauma are easier to see but unfortunately not as easy to treat. Treatment options for this kind of nail are varied and dependent upon the extent of the damage.
Not only is macrotrauma more difficult to treat but the outcomes are also more unpredictable. It may take years for a nail to recover or it may never recover at all. If the nail is damaged all the way down to the matrix (the base of the nail not the alternate universe), full recovery of the nail is more unlikely. And although the loss or change of a toenail is not the end of the world, there are options available if the look of your toenail is upsetting to you.
So now let’s look at the life of the party – fungi!! Toenail fungus, or onychomycosis, is an infection of the nail and nail bed which can be challenging to eradicate. It causes the nail to change in colour, thickness, shape and integrity. Sometimes, if the infection is significant enough, the toenail may fall off completely. In general, however, it doesn’t lead to any nasty consequences apart from the nail looking a little unique and sometimes the change in the nail may create some extra pressure in shoes or with neighbouring toes.
Toenail fungal infections come in a few different varieties including one that grows on top of the nail plate (which tends to be easier to treat). Regardless of the type of fungus, though, they all require patience, tenacity and compliance to get rid of. If you remember from before, a big toenail can take up to 18 months to regrow completely so it can sometimes feel like watching grass grow. They are also hard to diagnose, even under the microscope, as they can often mimic other things like psoriasis and traumatised nails.
There are all sorts of treatment options for fungal nails from over the counter lotions and potions to laser therapy or permanent removal of the nail. Treatment choices are largely based on how affected the nail is and what is important to each patient so it’s best to discuss these with your podiatrist.
Our nails also change naturally with ageing (along with everything else!) As we add a few extra candles to our birthday cakes, the nails tend to get thicker and lose their opaque colour. They can also curl under, curl around, become brittle and become more susceptible to fungus.
In general, microtrauma, macrotrauma and fungal nails won’t cause any serious long term consequences. There are, however, some weird looking nails that are more serious and need to be investigated sooner rather than later…
Subungual melanoma – not many people realise, but you can get melanoma under the nail plate. It resembles macrotrauma in the fact that it causes a dark discoloration to the nail but it is different in the fact that it doesn’t grow out with the nail, there’s no related incident to cause the bruising and often the discolouration extends to the skin.
Other nail tumours – there are a range of different tumours that can grow beneath the nail plate. As a general rule, benign tumours respect the basic formation of the nail whilst malignant ones destroy the nail. Either way, if you notice and unusual growths or lumps under the nail, it’s important to ask your podiatrist to have a look.
Clubbed nails – the nails develop a wide ‘club-like’ appearance. This can be a hereditary kind of thing but it can also indicate an underlying health issue such as heart disease, lung disease or cancer. If it’s something new that is happening, it’s important to ask your podiatrist about it