Halle Berry credits her youthful looks to bone broth.

The 51-year-old actress picks up bones from the butcher and boils them into a special drink, which she claims is ''full of collagen'' to keep her complexion flawless.

She said: ''You can make it, you can go to the butcher and get all the bones they're going to throw away and he'll give them to you for free. Take the bones, boil them up for 24 hours... and you drink the broth. It's so full of collagen that it's crazy.''

Meanwhile the 'Extant' star admitted it was a ''struggle'' for her to show her four-year-old son Maceo's face on her Instagram page for the first time while vacationing in Bora Bora last month.

Halle - who has Maceo with ex-husband Olivier Martinez and also has 10-year-old daughter Nahla with former partner Gabriel Aubry - wants to ''protect'' her kids while also letting her fans into her life.

She told 'Extra': ''That was a struggle.

''I really don't like to show my kids very much but I do realise my people are, like, solid for me and me for them and I feel like I want to include them.

''But it's a fine line because I don't want to exploit my children... I want to protect my children, so I thought, 'Half the face is good.'''

Halle - who has 2.8 million followers on Instagram - recently admitted she loves using the social media site as it's given her an ''outlet'' of her own.

She said: ''It took me a while. I was a latecomer... But you know, as an artist and as a woman that has something to say, it gives me my own voice, my own outlet.

''I can show the world through my eyes. I can talk about what I want to talk about and not talk about what I don't want to talk about...

''I'm the boss of my page! And if you don't like it, don't come to it, there's a trillion others.''