Hi, I am 17 years old. And I'm suffering from extensive hair loss since last 4 months. I unfortunately lost nearly half of my hair density. And this is due to my extremely low Vitamin D level (6 ng/mL). I got it checked last month and I'm taking my medications since then. It's so depressing and frustrating at the same time. But now all I want to know is that can my hair grow back as much as my earlier hair density? Kindly help me out. Thanks.