Kate Winslet is teenage son's go-to hair colourist

Kate Winslet has become the personal hair colourist for her teenage son and his friends.

The British actress, who recently became a global ambassador for beauty giant L'Oreal Paris, is known for colouring her locks, and she has revealed her 17-year-old boy Joe and his pals have been turning to her for help with their own style transformations.

"My son and his friends are also constantly wanting to change their hair colour so I often find that if he has them round, they'll be like, 'Mum, can we dye Jake's hair purple?'" Winslet told British Vogue.

The Titanic star is more than happy to oblige - but only after they've obtained permission from their parents.

"I'm terrible and tell them to phone their mums to check if it's OK," she said.

"How did I become the parent with all the cool hair dye in my house?" she marvelled. "But that's us and it's partly because I have a daughter and she's also always experimenting with hair colours and realising she bought the wrong one, so my son gets her cast offs. Absolutely hilarious."

Winslet shares Joe with her second ex-husband, Sam Mendes, and 20-year old daughter Mia with her first husband, Jim Threapleton. She also has seven-year-old son Bear with her current spouse, Edward Abel Smith.