What causes your nails to grow?

Anonymous
Before my nails didn't grow so much and my toe nails curved (ik disgusting) but lately i notice my white tips of my finger nails and toe nails. Their longer and my toe nails doesn't curve anymore. What causes this? I have been taking iron pills and drinking milk a lot lately thats the only difference do you think high amounts of iron and vitamin c can do this to the nails?
What causes your nails to grow?
3 Opinion