The Hills star Lo Bosworth has said she has battled crippling depression caused by a severe vitamin deficiency.

The former reality TV star said she started feeling “very off” towards the end of 2015 when she suffered insomnia, impulsive behaviour and a “racing mind”. She began therapy and started taking medication.

Lo Bosworth arrives for The 2010 MTV Movie Awards
Lo Bosworth (PA)

Writing on her blog The Lo Down, she said: “2016 wasn’t only just the worst year ever, it was also the year I turned 30, founded my own feminine wellness company, and brought an amazing puppy home.

“So not all bad. Light does find a way of shining through the darkness. And what is the darkness I’m referring to? Crippling anxiety and depression at the hands of a severe vitamin deficiency that went undiscovered for 16 months.”

She said her early symptoms all developed into “a feeling of anxiety that lasted for almost two months without any relief”.

She said: “Can you imagine having a 60-day-long panic attack? I can now – I lived it.”

Lo said her doctors were confused by her lack of progress after months on anti-depressants until a complex blood test looked at her vitamin levels.

TV personality Lo Bosworth arrives at the 2009 MTV Video Music Awards
(PA)

In a blog entitled “2016: The year of my great depression”, she wrote: “I’m told I have severe deficiencies of Vitamins B12 and Vitamin D. Want to know what happens if you’re deficient? You can develop, amongst other things, depression, anxiety, fatigue, headaches, dizziness, and a lot of other vague and uncomfortable symptoms. Want to know what happens if you never address your deficiencies? The symptoms can become permanent – yes, like permanent brain damage.

“What I know now is why my body doesn’t process B12 and D in the way that other people can. I also know how to handle this problem – which is by taking the highest quality, most bio-available methylated form of both every single day for the rest of my life.”