Michael Douglas described himself as a ‘healthy product of the Sixties’ as he opened up about his colourful love life.In his upcoming memoir One Helluva Ride, the 82-year-old actor reveals that he had an affair with Kathleen Turner while filming Romancing the Stone, despite still being married to first wife Diandra Luker.With the book also detailing his many flings over the years, and an anecdote that he needed to make ‘five quick calls’ when Catherine Zeta-Jones told him that she would only date him if he was monogamous, Douglas was asked by a British reporter if he ever wondered why he slept with so many women.Douglas responded: ‘I don’t know if I slept with so many women, I don’t see it that way. No, not me, no. I was a healthy product of the Sixties.’ He then added in an alleged ‘accusatory’ tone: ‘My curiosity is why, of all countries, of all the press that I do, why are the Brits so consumed with the issues of sex?’Douglas also stresses in his book ‘I was never a ***ing sex addict,’ following reports in the Nineties that he entered rehab for sex addiction. Michael Douglas, 82, has denied sex addiction rumours and says he was a ‘healthy product of the Sixties’ as he discussed his colourful love life (pictured with wife Catherine Zeta-Jones) In his upcoming book, Douglas finally admits to having an affair with co-star Kathleen Turner while filming their 1984 action-comedy, Romancing The Stone When it was noted that his memoir is ‘full of sex,’ he responded: ‘I didn’t feel like it was. I mention a couple [of women] in the book.’ Asked to clarify his anecdote about needing to finish with five women before committing to Zeta-Jones, 57, he told The Sunday Times Magazine: ‘No, no, it’s not what it was. ‘What Catherine said is, if we’re going to continue this then I want it to be monogamous. And so I therefore, that evening, you know, made some calls to some people I was seeing, and that was that.’ When asked if Catherine was nervous about his book coming out, he responded: ‘She hasn’t read it,’ yet insisted their marriage was ‘in good shape’. In the upcoming book, Douglas finally admits to having an affair with co-star Turner while filming their 1984 action-comedy, Romancing The Stone.In an excerpt shared by People, he penned: ‘Kathleen was smart, funny, and sexy with a deep, sultry voice that became her signature. I instantly liked her, and we were immediately attracted to each other.’He then claimed that his marriage to Diandra ‘was in a bad place’ and that he had been having an affair with Romancing The Stone screenwriter Diane Thomas prior to meeting Kathleen.Both Douglas and Turner, who was single but dating real estate mogul Jay Weiss – the man she would later marry – steadfastly denied the affair, too, even when Hollywood gossip reached fever pitch when Douglas’s then wife Diandra became so worried that she flew to the Mexican set and confronted her.But now, four decades on from the blockbuster, Douglas has ‘come clean’.In his explosive memoir, he recalls how he and Turner, now 72, fell madly in ‘lust’ at first sight: ‘Kathleen was smart, funny and sexy, with a deep sultry voice that became her signature. I instantly liked her and we were immediately attracted to each other.’The Fatal Attraction actor added: ‘Things at home were in a bad place. Diandra and I were both having extramarital affairs. The truth is that during the production of Romancing The Stone, Kathleen and I fell hard for each other and began a relationship.’It wasn’t a fly-by night affair; it grew naturally from how closely we were working together, how much pressure we were under, how much we respected and cared for one another, and how attracted we were to each other.’Like every other guy in the world at the time, I was knocked sideways by Kathleen.’ Douglas’ marriage to Diandra Luker limped on until 2000 when the couple divorced (pictured in 1997) – with Douglas marrying Zeta-Jones that same yearThe pair kept their affair hidden from everyone including their co-star Danny DeVito and director Robert Zemeckis.Douglas penned: ‘We found each other first as friends, then as co-stars, and finally as lovers.’Following an exhausting day of shooting in the jungle, we’d go out and have a meal, or head out with the group and afterward I would sneak into her hotel room after everybody was asleep.’Their clandestine romance ended when Douglas’s wife flew from LA to Mexico and brought their young son.He added: ‘Diandra grew suspicious. A woman’s intuition, I suppose.’Their marriage limped on until 2000 when the couple divorced – with Douglas marrying Zeta-Jones that same year.He and Turner had a ‘gentleman’s agreement’ never to discuss their relationship and for four decades both stuck to that pact.Douglas wrote: ‘The official story went as follows: Yes, we confessed, we had amazing chemistry. Yes, we were both, as Kathleen said, ‘terrible flirts’, and yes, we were both tempted, but nothing ever happened between us.’That was a lie. It was a lie meant to protect my wife and son, a lie we told the world for 40 years.’Turner honoured that pact in an interview with The Mail on Sunday a few years ago, saying: ‘The chemistry was there and Michael and I were both terrible flirts. We were in the jungle and I was feeling very romantic towards him. It was going to happen.’Then I walked on set one day and his wife was suddenly there. She sat next to him and that was that. You don’t mess with another woman’s husband.’When asked this week how she felt about Douglas ‘outing’ their illicit romance, Turner appeared far from upset: ‘Good heavens, what a fuss about something 40 years ago! I love Michael and I look forward to enjoying the book.’ Douglas met actress Zeta-Jones in 1999 and they married two years later. They welcomed son Dylan that year followed by a daughter, Carys Zeta, in 2003Turner and Douglas proved to be a box office draw, with Romancing The Stone grossing $115million at the box office.They reunited a year later for the sequel The Jewel of the Nile, but they kept their relationship strictly professional.They did a third movie together in 1989, The War of the Roses, which was another massive box office hit.Luker eventually filed for divorce from Douglas in 1995 after 18 years of marriage.According to several reports, Luker walked away with $45million and several homes.Douglas met actress Zeta-Jones in 1998 and they married two years later. They welcomed son Dylan that year followed by a daughter, Carys Zeta, in 2003.Douglas and Turner would go on to reunite once again, this time on the small screen in Netflix’s The Kominsky Method.Turner joined the show’s second season in 2019 and also appeared in the third and final season in 2021.They once again denied rumours of a past affair while promoting the series, leaving it as a four-decade secret.One Helluva Ride will be released October 6.