Charlize Theron has admitted to taking drugs in her twenties

Speaking to Howard Stern on his Sirius XM radio show, she said: "I cannot smoke weed any more, I become so uninteresting.

"I don't want to talk. I switch off and have nothing to say.

"In my twenties I was a wake-and-baker and then I couldn't do it anymore. I was like functioning and then one day I just sat on the couch and didn't move. Now I am asleep by 8.45pm and I f***ing love it. I wake up at 6.30am, I have to make two lunchboxes."

When asked if she did cocaine in her youth, she said: "I definitely experimented, yeah," and referring to ecstasy, she added: "I had a f***ing great time. I didn't do a lot of it but I definitely did in my twenties.

"I always worried in my twenties I would feel like if I had kids I would be missing out on this life and then I hit my thirties and thought I am so f***ing done with it."

Meanwhile, Charlize recently spoke out about being a single mother.

She said: "I'm a single mom and I have an incredible village that helps me raise these two beautiful kids. In the mornings, I have them alone and they kind of work against each other sometimes. One kind of decides to freak out and then both decides to freak out, I don't know why they decide to do that. You think they'd stand there and be considerate like: ‘well that one is freaking out right now, I'm not gonna freak out.' They don't do that.

"I'm an only child so I didn't grow up with siblings and so I had no idea the beauty that siblings have with each other. Like it really is one of the most incredible things I've ever witnessed. To see how much they love each other and to see how much they're excited to see each other. They're so in love with each other, it's really beautiful."