Nicole Beharie is opening up about a health issue she’s been keeping secret for years, and reveals it’s directly connected to why she left Fox time-travel drama “Sleepy Hollow”.

“For the last, like five years I’ve been battling an autoimmune condition,” she begins in a video she posted on Instagram.

“It actually happened while I was on ‘Sleepy Hollow’,” she continues. “For all those ‘Sleepy Hollow’ fans out there, that’s one of the reasons I had to [exit].”

Admitting that it’s “been challenging,” she adds that “in the next few weeks and months, I’m going to be sharing some of the things I have done to reverse the situation and to strengthen my body and my mind to get back to a place of sustainability and power and gratitude and ease.”

RELATED: ‘Sleepy Hollow’ Stars Tom Mison And Nicole Beharie Tease ‘Explosive’ Season Premiere

Speaking to “Sleepy Hollow” viewers, Beharie says they will likely recall “my weight was fluctuating, I had rashes… things have improved a great deal. I just want to share for the sisters and brothers and everyone else out there, that there are ways of changing your diet, some of them can be rather restrictive, but there are things that we can do to improve and optimize our health and our mental state. I look forward to sharing this with you.”

She concluded by stating, “There’s a lot of misconceptions about when people have health challenges and restrictions and I think you can get demonized for setting limitations and boundaries, but I think that is something that we can not allow to happen to our bodies as women, as people of colour. It’s important to own and master and love what we got.”

Beharie’s video clears up the mystery behind her abrupt departure from the show when her character, FBI agent Abby Mills, was killed off in the season-three finale, as an official reason for her exit was never given.

“There were a variety of factors that led to the end of the season,” then-Fox network chief Dana Walden said in a 2016 conference call, addressing fan furor over Abby’s death.

RELATED: ‘Bones’ Plans Crossover With ‘Sleepy Hollow’

“It was not a decision that we wanted to make initially,” Walden said of Beharie leaving the show. “We ended up being put in a situation where that was a decision that needed to be made.”