The Hills alum Lauren "Lo" Bosworth, who was a solid sidekick to Lauren Conrad through its last three seasons, has done a lot of things since leaving the Laguna Beach drama circle in the rearview. She's authored a book (2011's The Lo Down), founded a party supply company of her own, and has pumped out YouTube instructional videos covering the gamut of how-to life hacks, from making almond-shaped nails, to nutritional pointers for a gluten-free diet.

But she's also endured a major personal struggle behind the scenes.

After a months-long stint of absence from her YouTube page, Bosworth returned last week with a new video guide for prepping meals for a week in advance, prompting many comments from her followers asking where she'd been hiding all this time.

To answer those questions and offer up an entirely new sort of advice line, Bosworth then followed that up with a video in which she explained her decision to step away from her own camera.

"I have been dealing with some pretty serious health issues since late 2015, and I'm better now," she explained. "I just wanted to be honest with you guys and tell you what was going on. So, for the past 16 months I have not been feeling right in the brain, in my body, just kind of ill all the time."

Bosworth then explained that she'd been in treatment for months before a doctor finally suggested testing her for vitamin deficiency, and, despite her careful attention to nutrition, she was severely depleted of vitamins B12 and D, which can result in symptoms of anxiety and depression.

"To finally get something back that showed very clearly that something was absolutely wrong inside of me was just kind of shocking," she added. "I wanted to make this video as sort of a personal PSA to tell you all that if you're feeling off, and you can't figure out what it is, and you seem to be getting worse and worse no matter what you take and what you do, definitely have a full blood screening done that goes beyond your white blood cell count. You have to be your own advocate for these things."

In addition to the personal video account, Bosworth also blogged about her experience grappling with her "crippling anxiety and depression at the hands of a severe vitamin deficiency that went undiscovered for 16 months."

"Depression and anxiety can be both emotional and physical, and having lived through it, all I can say is that the struggle is worth it," she wrote. "I'm living proof that you should fight, you should explore, you should take your health into your own hands and be your own advocate, and that you CAN come out the other side with some serious scars, but feeling like a brand new human being."