Have you ever had those little white spots on your fingernails? They're called punctate leukonychia - which is just a medical term that means "white spots."
Want to know what makes them show up? There are many reasons. The most common reason: your nail suffered some amount of trauma getting banged or slammed. The white spots are no cause for alarm and they will just grow out over time.
Now, if you use nail polish, hardeners, or artificial nails, those white spots might have been caused by an allergic reaction.
You could have also picked up those spots at the gym or during your last manicure - namely a fungal, yeast, or bacterial infection that attacks the nails, leaving a whitish spot or streak. A quick visit to the doctor can determine if there's a pesky organism causing those spots - nothing a little medicine can't take care of.
Skin disorders, such as eczema or psoriasis, can also leave spots on your nails. Don't worry - just having the spots alone doesn't mean you have a skin disorder.
If your entire nail has turned white, it could be a nutritional deficiency, like a lack of zinc or protein.
Fit's Tips: If you have a sudden explosion of white spots on your nails and haven't recently slammed your digits in the car door, I'd make an appointment with your doctor to get them checked out.