Why do I have white spots on my nails?

To understand where white spots come from, we must first explain how nail growth works.

If you’ve ever had white spots on your nails before, you may have been dismissively told that it's down to a lack of calcium or zinc. Basically, some mineral-deficiency. But this popular belief doesn’t really have any basis in fact. According to Healthline, nails grow an average of 3 millimeters per month. Their composition is made up of keratin, a protein, and just 0.03% calcium. So white spots are certainly not just a calcium problem! 

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