Kelly Preston says she gave up drinking to become a better mother.

The 49-year-old actress – who has two kids, Ella, 12, and 18-month-old Benjamin with husband John Travolta – admits she is "so much wiser" after giving birth to Benjamin in November 2010 as she used to smoke, drink and do drugs but she opted to change her ways for the sake of the couple's kids.

She said: "It's different in that I'm so much wiser. I know myself so much more now.

"I'm so different, too. Now I don't drink anymore. I don't smoke anymore. I don't do drugs anymore. All of those come with an 'anymore.' I used to do everything and a lot of everything.

"With drinking, I just decided that I wasn't always at my best. There were times where I drank too much, for sure."

Kelly says her and John's children are "the centre of our universe" and they have been "so extraordinarily" helpful in her life.

In an interview on 'The Conversation with Amanda de Cadenet', she added: "For me, I find that our kids came in half the time to teach me about myself and to help me with others, and they have helped me so extraordinarily."

The couple – who have been married since 1991 - were left devastated in 2009 when their eldest child, Jett, died aged 16 after hitting his head during a seizure while in the Bahamas.

Kelly's interview was filmed months before John was accused of sexual harassment by two male masseurs and a Chilean-born cruise worker earlier this week. John's lawyer Marty Singer vehemently denies all three allegations.