Movie sets can be lonely, says Lupita Nyong'o

Actor Lupita Nyong'o says spending time away from family on a film set can be an "isolating" experience.

The 36-year-old actor, who is fiercely protects her personal life, also said privacy is "a commodity that is hard to come by".

"Filming is so time-consuming. And intense. With 'Black Panther', a lot of us were single. On 'Little Monsters', nobody was single.

"Everyone, when they're done with their day's work, wants to go home to their families, which makes a whole lot of sense. When you don't have that it's very isolating," Nyong'o told British Vogue magazine.

The "Us" star said she attaches herself to a project when she is "seduced" by its potential to change the narrative.

"I don't get fulfilment from the number of zeros attached to a project. What I'm seduced by is the potential to shift a narrative. That is very seductive to me, having social and cultural impact," she said.

"I definitely want to claim ambition, but I get very compulsive about the things I am passionate about, to the point of not sleeping. It's very impractical. I fight the barriers that I form for myself, because they're often ridiculous," she added.

The Oscar winner, a vocal advocate of women's rights and environment among others, said she speaks up for causes she can "personally vouch" for.

"There's a lot going on in this world, a lot of causes that are noble. But I feel most useful when I have a personal connection. And the conviction to say something," Nyong'o added.