Oprah Winfrey helped Alicia Keys find ''joy'' in her work.

The 39-year-old singer took some life-changing advice from the 66-year-old talk show host after she felt ''overworked'' having let down her boundaries and said yes to everything her agent threw at her.

Speaking on the 'Happy Place' podcast, she explained: ''I would be so overwhelmed or overworked - I was just saying yes to everything and then I'd be exhausted. And there's no joy, it steals your joy.

''That was a big lesson that actually Miss Oprah shared with me. She said to me that she had also experienced that and how she was always looking outside of herself for the answer.

''And she finally realised that she's the only one who knows herself, and we're the only ones who truly knows what's good for us and only us.

''She started to say, 'You know what a resounding yes feels like'. Today, that sounds so obvious but in that moment no one had ever explained it so simply.''

Prior to her meeting with Oprah, the 'Superwoman' hitmaker ''willingly'' through herself at every opportunity in hopes of getting to the next stage in her career.

However, she eventually learned how to say no to people to be able to enjoy her success and have some well earned time off with her family and friends.

She added: ''I do think boundaries is amazing. I didn't have any, I had none. I had no boundaries, I didn't even know how to put them in place. In fact, I gave them away willingly, happily, gratefully.

''Just to hopefully go to the next step or what I thought was closer to what I was hoping for, or what I thought would make whomever - you know, doors open or possibilities come in regards to my career as an artist.

''I didn't understand that you could say no. It took me so long to know on tour I could say, 'Oh this is my someone special to me birthday. Let's make sure that I'm not working on that day.' I didn't even know how to do that. I think things like that in regards to boundaries are really important.''