Jennifer Aniston admits she had some reservations about doing a sexy strip-tease dance in an auto-body shop for her new big-screen comedy "We're the Millers." The actress, who is trying to explain her marital rumors, is busy promoting the movie but would also like to settle the marital rumors that she is having problems with Justin Theroux.

"I would say that was a challenging one for me. I just had to do it. We rolled the cameras and I just had to bite the bullet," the 44-year-old actress told reporters in New York Saturday.

"It was a little uncomfortable at first, but then you get into it. Doing the rehearsals alone with [the choreographer] and then all of a sudden you're on the set and there's three cameras and a bunch of crew. Yeah, it was a little intimidating at first."

Told she looked amazing in the movie and asked for advice on how others might follow her lead, Aniston replied: "No secrets and it's not a few tips.

"I don't think you have time for that answer. It was an amazing choreographer and wonderful trainer and a beautiful cinematographer. All that good stuff. And I worked out a lot."

So, did she avoid eating carbs during the shoot to maintain her physique?

"Oh, no, no, no. No food. There were a lot of salads. Celery sticks. Cucumbers. Ice chips. They did let me eat ice chips. Water was good. You could eat normally. But no carbs," she said.

In the film, Jason Sudeikis plays David, a small-time Colorado drug dealer whose pot stash is stolen, forcing him to promise his supplier he will transport a load of marijuana across the Mexican border into the United States to repay him for what he lost. David's boss, played by Ed Helms, even offers David a hefty bonus as part of the deal.

Jennifer Aniston doesn't have that squeaky-clean image anymore after this striptease

Figuring a squeaky-clean-looking family in a recreational vehicle will draw less attention from authorities than a single man traveling alone, David enlists three people he barely knows to pretend to be his wife and kids.

Although David's stripper neighbor Rose; Kenny, a sweet, but clueless teen who lives in their apartment building; and Casey, a self-absorbed, homeless girl, initially agree to the road trip because they are lonely and cash-strapped, the quartet of unlikely drug smugglers bond along the way, developing real affection for each other.

Aniston and Theroux, 41, began dating more than two years ago and got engaged on his birthday last August. Since then, their indefinite plans have led to speculation ranging from a broken engagement to Theroux getting cold feet.

Not true, says Aniston.

"We have yet to set any dates. There have been no canceled weddings. There have been no postponed weddings. There have been no arguments about where to get married. Just clearing all that up," she said.

Aniston plays Rose, while Will Poulet plays Kenny and Emma Roberts plays Casey in "We're the Millers," which opens in theaters nationwide Aug. 7.