Model Anna Nicole Smith has admitted that she is now satisfied with the size of her breasts, after undergoing five operations to get them back in their original state, and has also explained that just like tyres they need changing from time to time.

"You get scar tissue. You have to go in every five years and change them out," the Sun quoted the 37-year-old as saying.

Anna's boobs almost disappeared due to her weight loss when she gave birth to her son in 1986, but she finally got them back in their original state and then oversized them, after putting in years of efforts.

However in the process, she went from too small to too big.

"I went up to 211 pounds so I stretched to double-Fs, and when I lost all the weight I went way back down, except my skin didn't. It was not pretty," the paper quoted her as saying.

The star, who has refused to disclose the current cup-size of her bra, has refuted claims that she underwent two implantations to increase her boob-size.

"I've heard a rumour that I have two implants in each boob. Now, if anyone could show me how that would work I'd really like to see it myself," she said.