It's been 15 years since Friends finished, but it's still one of the most beloved shows around.

And while many of us still enjoy watching the re-runs and streaming it on Netflix, we also still enjoy learning new things about the cast.

But one of the core six has just revealed something that will probably leave you feeling rather sad.

In a recent interview, Lisa Kudrow, who played Phoebe Buffay on the sitcom, admitted that she struggled with the way she looked while filming Friends.

Speaking on Marc Maron's podcast, WTF With Mark Maron, the 55-year-old explained how seeing herself on screen next to her female co-stars, Jennifer Aniston and Courteney Cox made her feel like a "mountain of a woman".

She said: "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 - bigger, like my bones feel bigger. I just felt like this mountain of a woman next to them."

She went on to explain how the pressure of being an actress drove her to become "too thin", which meant she was "always sick".

Despite this, she claims others around her would tell her how good she looked when she was underweight.

"Unfortunately for a woman, if you're underweight, you look good," she added. "And that's all I ever got."

And even today she still struggles sometimes with the way she looks, saying it's an ongoing "battle".

This comes after Kudrow told Entertainment Tonight   that she can't remember the last time she saw an episode of Friends and she doesn't have an interest in seeing one.

Her reason for this was to stop herself from criticising her performance.

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