Lisa Kudrow says she felt like a "mountain of a woman" next to her Friends co-stars. 

Few characters have entered our lives via the small screen as iconic as the ever-endearing Phoebe Buffay of Friends.

I mean, come on:

While for some of us (we’re calling it – most of us), she was our favourite member of the gang, behind Phoebe’s quirky nature and tell-it-how-it-is approach, actress Lisa Kudrow was battling daily body confidence issues on set.

Kudrow, who was 31 during the first season of Friends, said on this week’s episode of podcast WTF with Marc Maron that she couldn’t help but compare herself to co-stars Jennifer Aniston and Courteney Cox.

The two types of work wives. Post continues after video.

When asked about the pressures of maintaining her physique while starring in the popular sitcom, the 55-year-old said it was never easy, adding that watching herself back on screen would often fill her with insecurity.

“You see yourself on TV and it’s that ‘Oh my God, I’m just a mountain of a girl’… I’m already bigger than Courteney and Jennifer, like my bones feel bigger,” the mother-of-one told host Marc Maron. “I just felt like this mountain of a woman next to them.”

The actress revealed that at times, she'd go to great lengths to fit Hollywood's idea of the "perfect body", even sacrificing her health to stay thin.

“Unfortunately for a woman, if you’re underweight, you look good,” she said. “When I was too thin I was sick all the time, a cold, sinus infection, I was always sick.”

Nowadays, Kudrow admits her battle with body image still rears its ugly head from time-to-time, but adds that she's learnt to accept the physical changes that come with ageing.

“I just go, ‘All right, so what? You’re older that’s a good thing, why is that a bad thing?’"

In a previous interview with ET Online, Kudrow said she refuses to watch Friends reruns.

"I don't watch it if it's on," Kudrow shared. "I might not like myself [on the show], so I'd rather not risk that."

Kudrow's new film, Booksmart, follows two straight-A high school students, Amy (Kaitlyn Dever) and Molly (Beanie Feldstein), who decide to cut loose in their final weeks of school.

Kudrow, whose son Julian Murray Stern is 21, plays Amy's mum.

For the actress, the film is a throwback to her own celebrated 1997 high school comedy classic, Romy and Michele's High School Reunion, in which she starred opposite Mira Sorvino.

"Even though [Romy and Michele] were idiots and these girls are really smart - and it was about a different time with a completely different tone - it's ultimately about best friends," she said.