The "Mean Girls" star told the magazine in an interview accompanying her 10-page nude pictorial that during the past five years she's come to understand "that ultimately we are responsible for ourselves and our own actions."
Magazine founder Hugh Hefner has said he advanced the street date of the highly-anticipated issue -- in which a blonde Lohan channels her idol Marilyn Monroe's famed 1953 Playboy photo spread -- in part because photos were leaked online.
The Lohan issue hit Playboy's website on Saturday and the magazine lands on newsstands December 16, one day after Lohan's scheduled interview on Ellen Degeneres' daytime TV talk show. Excerpts of the Playboy interview were released on Saturday.
The former child star whose career has suffered in recent years following arrests for drunken driving, drug possession and theft, told Playboy she would have done things differently in her recent years of trouble.
"Looking back, I probably would have listened to and taken more advice from the people whom I admire and would have followed through with it more," Lohan said.
"My stubbornness at 18 and 19-years-old got in the way," she said. "During the past five years, I've learned that time flies faster than you think, and because you only live once you have to learn from your mistakes, live your dreams and be accountable."
In November, Lohan was sentenced to 30 days in jail for violating her probation on recent criminal charges, but served less than a day behind bars due to overcrowding.
In an excerpt that apparently references her decision to pose nude for the magazine, Lohan said: "Sex and sexuality are a part of nature and I go along with nature. I think Marilyn Monroe once said that."
And the actress, who first gained fame playing twin sisters in 1998 Disney film "The Parent Trap," said she doesn't understand why her life has become tabloid fodder.
"I have no idea why there is this fascination with everything I do," she said. "I suppose it is all part of this trend of people wanting to know every single detail of a celebrity's life.
"I mean, once we get to the point where magazines are doing pictorials on my wardrobe to court, that's just so unimportant," Lohan said.