Lena Dunham: Girls talk

At 26, Lena Dunham is the creator and star of the most talked-about TV show in America. Here, she wins another fan in Sarah Hughes

A lot can happen in a year. The first time I talk to Lena Dunham, it's early 2011. Tiny Furniture, the second film she's directed, written and acted in, has just opened to strong reviews and she's begun filming Girls, a much anticipated sitcom for HBO produced by comedy king Judd Apatow. Not quite 25, she is garrulous, entertaining and open, perhaps overly so: she ends our interview by giving me her email address.

The second time we talk it's 2012, and Girls, an off-kilter look at the lives and loves of four twenty-something women in New York has become the most talked-about show in America. Now 26, Dunham also writes, produces, largely directs and stars in it, as wannabe writer Hannah Horvath. In the process, she has become a phenomenon, so in demand that, as reported last week, bidding by publishers for a proposed collection of autobiographical essays about sex, friendship and work, tentatively entitled Not That Kind of Girl, has reached $3.6 million.

So, what "kind of girl" is Dunham? My initial thought is that the person who turns up for our interview in a chic, fitted grey dress, with shiny hair and subtle make-up, seems far more polished and far less likely to share her contact details with strange reporters. But then she starts talking about her homesickness since moving to Los Angeles and it's clear the immaculate front is just that.

One of the most resonant things about Girls is the way it captures that period in your early twenties when you're supposed to be a grown-up but still feel young and confused. It's how Dunham herself still feels, at once declaring, "I'm a control freak", and admitting she can't quite cut the family apron strings. "I was just talking to my dad," she says. "He said, 'You're not getting enough sleep, come and talk to my doctor, get some vitamins from him.'" She giggles. "He still thinks I'm six years old."

The daughter of two renowned New York artists, Dunham readily admits to plundering her life for inspiration – "most of Hannah's mistakes are mine, only she makes, like, six of them in one episode; mine are more spread out."

In fact, her chief concern is not whether people like Girls but whether they find it honest. "The thing about Hannah is she's not constantly endearing. She's frustrating and complicated and weird and annoying," she says. She's also refreshingly real. Dunham's most interesting decision, one that has brought her equal amounts of opprobrium and praise, is to consistently display Hannah's (and by extension her own) body.

In an era when the female body is expected to be toned, tanned and taut, hers is pale, tattooed and unapologetically ordinary – and under the camera's harsh light, nothing is spared. When Hannah sits in the bath, we see the slight pudginess around her stomach. When she has sex, it's often awkward and ungainly. These are fascinating scenes because they're so rarely seen on TV, where sex is always either perfect or played for laughs, and young women saunter undressed through sitcoms so that we can admire their polished perfection. Dunham's honesty seems both admirable and brave.

Not that everyone sees it that way. Most notably, one female critic complained that Dunham "courted our rejection by walking around the house in nothing more than a T-shirt, flaunting her ass and thighs". Dunham chose to play off that comment at this year's Emmy Awards by taking part in the show's opening skit naked, and eating cake.

"It's comforting to me that a number of women do obviously understand where we're coming from," she says. "It was realistic to show Hannah wandering around in her T-shirt and having conversations in the bath. That's who she is."

She offers a similar defence on the first episode's riskiest line, when Hannah, liberated by a cup of opium tea, announces to her parents: "I think I may be the voice of my generation."

Dunham admits: "I knew it was a dangerous thing to put in, that people might say, who does this bitch think she is? But she's on opium, she's grasping at straws …. You're supposed to laugh at the character as much as with her." It's notable too that Hannah follows this with the amendment "… or at least a voice. Of a generation". It's a typical Dunham moment, undercutting a perceived arrogance with self-aware doubt.

What then of the accusations of privilege? Dunham grew up in Manhattan's Tribeca and attended St Ann's, an artsy private school in Brooklyn Heights, before going to university at the equally artsy Oberlin. Girls' other three stars had famous fathers: Zosia Mamet is the daughter of playwright David; Allison Williams, of NBC anchor Brian; and Jemima Kirke, Dunham's school friend, had former Free and Bad Company drummer Simon Kirke for a dad.

When we first met she joked that her then untitled show might as well be called the "Lena Dunham Project". Today she offers a more serious response. "Working with my friends makes me safe," she says. "That said, I really didn't know Allison until she was cast ... and then it was funny to realise that Brian Williams was her father. My real hope is that people recognise that they are all very talented and they've done a great job."

It's a polished answer, but then Dunham has become adept at defending herself and her show. Early in Girls' run, there was a furore over its lack of racial diversity. Speaking at Fortune magazine's Most Powerful Women summit last Tuesday, she said she felt "heartbreak at the idea that [Girls] would make anyone feel isolated… all I want to do is make women feel excited and included." To that end, the second season will have a more diverse cast, including rising comedy star and rapper Donald Glover, and Dunham told the Fortune summit that she's working hard to respond directly to fans "who are women of colour who want to see themselves reflected on screen".

"When I wrote Girls, I drew very heavily on my experiences - all the characters are a piece of me or based on people I know," she tells me. "It speaks to a very specific kind of experience … my biggest influence was those 1960s/'70s films about young girls trying to make it in the city – Georgy Girl, Girlfriends ...."

But what of Sex and the City? Before Girls had even aired, its settings and basic premise had seen it compared to the early Noughties sitcom, despite its very different tone. "I thought about this a lot ... and the key is that this is a show about girls whose expectations were formed by Sex and the City," she says. "They've grown up thinking, 'that's what life in New York is like'. A lot of the humour is drawn from the differences between those dreams and the reality."

In any case, Girls' dry, singular voice is closer to that of great female comedy writers of the 1970s and '80s, such as Nora Ephron, a heroine of Dunham's, and Saturday Night Live comic Gilda Radner. "It's amazing to be compared to people like that," she says, sounding awe-struck. "I think honestly I have very modest ideas. I don't have cinematic references. I stick with the sense of humour I know." She pauses, then adds with a sense of genuine surprise, as though still struggling to grasp the ways in which her life has changed over the past year. "I always think of myself as too much of a weirdo to have a voice that will reach a mass audience. I can't quite believe all this is real."

'Girls' starts on Sky Atlantic, at 10pm on 22 Oct