1. Discoloured nails
Cause: You wear dark nail polish. Red, purple and other dark lacquers have pigments that can cause yellowing if they are not swiped off within two weeks.
Remedy: Discoloured nails aren’t pretty but there are plenty of ways to fix them. Change polish more often, or use acetone-based remover, which is strong enough to take off both the colour and yellow. If you use non-acetone remover, follow up with a little lemon juice. To prevent yellowing in the first place, always apply base coat before polish; it keeps colour pigments from reaching and staining the nail surface.
2. Fungal infection
Cause: You love to be barefoot: Going shoeless puts you at greater risk for catching a fungal infection; microorganisms outside or inside (say, a gym locker-room floor or swimming pool) can get into tiny cuts (like a torn cuticle) and work their way under your toenail. Signs of a problem include a whitish-yellow colour, then thickness and crumbling. In the last stages, the nail lifts away or comes off completely.
Remedy: If you spot the signs early (when the nail begins to yellow), ask your doctor for a prescription to stop the infection.
3. Detaching toenail
Cause: Your toenails need trimming. If toenails reach past the tops of your toes, nails’ tips can bump against the inside of your shoes. Over time, this damages the nail and, bit by bit can cause it to detach. Parts that have disconnected will look opaque and pale yellow. You may also notice a blackish bruise (caused by broken blood vessels underneath the nail).
Remedy: If this kind of damage continues, the nail will fall off or, in some cases, will be
required to be removed by a podiatrist or a dermatologist. To prevent this toenail trauma,
trim nails regularly and choose footwear that allows you to wiggle your toes.