The Dutch-English brunette was working as a personal assistant to Beckham when he was playing for Spanish club Real Madrid in 2004.
She sold the story of their fling to British tabloid the News of the World, putting Beckham's marriage to former Spice Girls star Victoria under intense public scrutiny - but despite standing by her decision to go public, Loos now admits she should not have wreaked such havoc on the famous family.
Loos tells British Tv show Daybreak, "Obviously I am a mother now and married... Knowing what I know now I would definitely have gone about things quite differently. I think I was quite young and foolish and very reckless and obviously didn't think things through. I just acted on impulse and I think I am a lot less like that now, hopefully."
Asked if she regrets the impact of her revelations on the Beckham clan, Loos replies, "Probably. Yes, I think I do. I think I regret the impact on everybody. I think I maybe could have gone about it in a kinder way. I don't regret speaking out but I regret the way I went about it... It was a whirlwind. I think in the end I paid a price. I could be quite lonely and depressed."
Loos now lives in Norway with her husband Sven Skaiaa and their two-year-old son Magnus.