Jake Gyllenhaal's mother was "worried" about his dramatic weight loss for 'Nightcrawler'

Speaking to E! news, he said: "I'd say my mother was worried [about the weight loss]. I would say she just wanted me to be careful. But she also knew and knows how seriously I take what I do and she respects that.

"She knows that I'm a big boy and I could handle myself and that I would stay within the realm of being safe, but yes, she worried. She'd be like, 'You're cranky--eat something.' "

Meanwhile, Jake recently fuelled rumours he was dating his 'Southpaw'

co-star Rachel McAdams after they were spotted out together on a number of occasions, and friends believe the hunk was instantly attracted to the 35-year-old actress during filming.

A source said previously: "There is no denying the electric chemistry between Jake and Rachel. The attraction was instant. From the moment they started working together, Jake and Rachel just connected intellectually and emotionally.

"For Jake, Rachel is the complete package. She's incredibly smart and well versed in arts, politics and culture, but she's not a show-off.

Of course, it helps that she's gorgeous."