The older model: Daphne Selfe

Do models eat biscuits? Daphne Selfe does. "And cake," she says – "Are you sure you won't have a sandwich?" – before we sit down in the living room of her Hertfordshire home.

You may recognise Selfe from the fashion pages of the Guardian, or from Vogue, advertising campaigns and style magazines such as Dazed & Confused. She has been shot by Mario Testino, Rankin and Nick Knight. She is 83, and last year appeared more in demand than ever.

Her long silver hair has become her trademark, though today it's pinned back. "I think it's fine for a woman of my age to have long hair," she says, "but I think we should wear it up." She's happy to talk and talk, so I let her get on with it while I study her face. Her cheekbones are sharp, her blue eyes shine and her skin looks lived-in and luminous. Her secret? "I have an Irish family behind me, which is good for looks," she says with a smile. "But everyone can look lovely. It's what's in your head that counts – your outlook."

As a young woman, Selfe wanted to work with horses and helped run a riding school. Then she moved to Reading and got a job in a department store. When a local photographer organised a modelling competition, the shop girls applied and Selfe won. After that, she trained with an agency – "We were taught how to walk, how to do hair and make-up, because in those days you had to do all that yourself. It's not like now, when you have all these people to transform you."

Around the same time, she met her future husband, Jim. Soon after, they were married with three children, and Selfe gave up modelling. Did she miss it? "No! With three children? That was what you did. You expected to give up work when you got married."

In the 60s, Selfe considered going back to modelling and approached a few agencies. "No way," she says, with a dramatic eye roll. "They didn't like the look of me. It was people like Twiggy and Jean Shrimpton. I just didn't fit." Was it a terrible rejection? "No! As a model you have to learn to be rejected. I know if I do five auditions, I might get one. And if I don't, so what?"

Not until 1998, aged 70, did Selfe – by then a widow – get her big break. The label Red Or Dead was looking for older models for its London fashion week show and Selfe, who had stayed registered with an agent, was cast. The stylist suggested she contact Vogue, which was working on an issue celebrating age. At the shoot, she met a scout for Models 1. "And I haven't looked back."

The fashion world has changed since she first became a model. Then she was a size 12 – "A strapping girl" – but now the standard size is a six or eight. "That's much too thin. If you're very tall, you've got to have some flesh on you. I don't think being too thin is awfully pretty."

She has undoubtedly stood up for diversity in a world that venerates youth. "People now get to 40 and think, 'Oh my God', but so what? Everybody has to get old."

We are not used to seeing older people presented in a sexy way – and Selfe has done some sexy shoots. She nods. "I don't mind. I used to be an artists' model. What upsets me is the way older people don't bother any more. I never go out without make-up. I do my hair."

She would never have cosmetic surgery. "Or Botox. I think it's a shame. Somebody I know went to America and they said, 'All these people with these fabulous faces, then you see them on the beach and they've got wrinkly bodies.' Why?" Selfe puts her good skin down to her genes, exercise, good diet and skincare. Does she mourn her youthful beauty? She shakes her head. "Age just makes you a bit slower." She thinks for a while and then smiles. "I can't wear high heels now, but I'm not bothered."

What makes a good model, and whom do you admire?

Bone structure, attitude – and a good agent. You've got to be very adaptable. I like Gisele Bündchen.

What have you eaten today?

Every morning I put carrot, celery, apple and ginger in my juicer, and I make my own muesli. I'll have a proper lunch – chicken or salmon with rice and lots of vegetables. I don't eat as much red meat as I used to. I'll have a piece of cake at tea, then soup for supper. I drink a lot of water, but I barely drink alcohol now. I might have a quarter of a glass of wine at dinner.

What was your worst job?

An ad I did for Bupa – I was photographed in a swimming pool with no heating.

Would you recommend modelling as a career to your granddaughter?

Yes. It's fine as long as you know what you're letting yourself in for, are strong-minded and take it with a pinch of salt. Some people [in the fashion industry] can be very rude.

Who is your favourite designer?

Etro – it's bohemian but wearable. I like unusual clothes. I don't like to go out looking frumpy.

• Interview by Emine Saner

The feminist model: Charlotte Free



Charlotte Free: 'It’s ridiculous that women have to shave their armpits and legs every day. I don’t have time.' Photograph: Getty (3); Camera Press (2)

Which came first, I ask Charlotte Free, the attitude or the superhero surname? "It's my real name!" she laughs. "All my family are crazy Frees. It's something I take a lot of pride in. Since I was a tiny kid, people were always saying, 'You're a free spirit.' I couldn't think of a better word to define me."

Charlotte Free has bright pink hair and unshaven armpits. Not so strange for a teenager making electronic music, staying out all night clubbing and playing video games; slightly more unusual for the supermodel of the moment, walking for Vivienne Westwood and Chanel, shooting for Vogue, V and Wonderland. There's even a Fuck Yeah Charlotte Free Tumblr fan page, where teenage girls (and probably grown women) around the world lust over her "yeah, so what?" style.

And Free is for real. There's no crack styling team behind her punky hairdo. "I've had pink hair since I was 15," she says in her sleepy Californian accent. So is it a punk statement? "It wasn't really about that. Ever since I was a kid I've wanted rainbow hair."

Free, now 19, grew up in the suburbs of LA, and you get a sense of a bohemian, rather laissez-faire upbringing. She describes her family as "working people" who are highly intelligent and creative. Her teens were spent going out dancing to electronic music, getting into trouble and "being wild". Did her parents mind? "My parents met while they were out. They've always been heavily involved in the music community, so it was kind of inevitable that I would inherit that."

A year and a half ago, a photographer spotted her in an arcade playing video games – a story that could come straight from a Lana Del Rey song. He took her to the IMG offices in New York and said, "This girl with pink hair is going to be a model." They signed her straight away.

But the fashion industry isn't about being free. Models are clothes horses, pummelled into shape to suit the whims of bookers, designers, make-up artists and hair stylists. I ask Free if she thinks she can survive. "I'm strong, and I've become stronger. I've turned down jobs because they've told me to bleach my hair. I shouldn't have to. If they don't like me, they can find another blond, blue-eyed girl – there's thousands of them." So she really won't lose her pink hair? "I might stop dyeing it because it's in pretty poor condition. I may go blond again, but it will be because I want to."

Free knows that women's hair is a battleground, and she's fighting for control on all fronts. The photographer Terry Richardson recently posted some photos on his website: close-ups of Free, pink-lipsticked, tongue out, arms in the air and armpits defiantly unshaven. It's a powerful image. Is it a feminist statement? "Absolutely!" Free says, shocked that I would wonder. "It's an equal rights thing. It's ridiculous that women have to shave their armpits and legs every day. I don't have time. I think it's asinine that men have this standard that women should be perfectly shaven." But how can she keep it up in fashion? "I only shave them once in a blue moon for a really big job. I like to keep my body hair. It's a symbol of how I'm not going to conform to something that's so ridiculous."

Free insists she won't compromise her beliefs. "I'm not scared of anyone. I stand up for other girls in the industry. If I see someone taking pictures backstage, I'll grab their camera, expose their film or delete all the photos. If you're taking photos of 16-year-old girls naked, you will not get away with it. It's paedophilic."

But if the fashion industry gets sick of her attitude, does she has a plan B? "I don't know. I love science and I've always wanted to study botany, but before modelling I had nothing. I had no money, I wasn't doing anything. Even so, I've always told myself I would go back to that if it meant being able to stand my ground. Nothing is worth changing who I am, or doing something I don't feel I should do.

What makes a good model?

Someone who can be themself.

What have you eaten today?

I haven't eaten yet because I haven't had a chance. I'm going to pig out this afternoon. I eat a lot of pizza and fast food, I don't weigh myself and I don't diet. I don't think my weight matters.

What is the worst thing anybody has said to you?

Vice magazine posted that I had only a week or two left because I looked so thin that I would die. I got in touch with the writer on Facebook and told them personally that was a wrong thing to do.

Who is your favourite designer?

I love Vivienne Westwood. She's original and a good person.

• Interview by Becky Barnicoat

The male/female model: Andrej Pejic

Andrej Pejic: 'Women’s clothes are less restrictive; I definitely have more fun with womenswear.' Photograph: Mert and Marcus/Art Partner

At the age of 14, Andrej Pejic liberated himself. For years, he had tried to be a conventional boy – he'd stopped playing with Barbies, he'd started to wear baggy clothes and caps, he'd even had a go at Aussie rules football. But it just didn't seem right, and the more laddish he tried to be, the more the other boys called him gay or a girl.

So he went with his instincts. "Liberation came in a bottle of bleach," he laughs. Out went the sandy-brown hair, in came the blond bombshell. To some he was a ridiculously beautiful girl, to others he was an even more ridiculously beautiful boy. He was happy to occupy an androgynous halfway house that defied definition.

Pejic has always felt something of an outsider. He was born in Bosnia to a Bosnian Serb mother and Croat father. When he was two months old, civil war and ethnic cleansing ruptured the country. His father's family no longer welcomed his mother, his mother's family no longer welcomed his father. His mother (then a judge, now a teacher) fled to Serbia with Andrej, his older brother and their grandmother, where they lived in a refugee camp. Meanwhile, his father, an economist, obtained a divorce without their knowing.

"The most traumatic thing I remember is the Nato bombings," he says. "I was seven and there were bombs falling close to us. Everybody lived in fear."

At eight, the family moved to Australia. He was a girly boy in the ultimate macho land. "As I got older, I saw the differences in the way men behaved, and I tried to suppress my feminine side – but it wasn't a perfect act. People noticed that in the playground."

It was when he dropped the act that Pejic began to feel at ease with himself. "I acquired a lot more friends, became more social and I didn't get bullied. So the way I look now is the way I looked from 14/15."

How did his mum react when he adopted his androgynous look? "I wouldn't say she was the most forward-thinking, modern woman. In the beginning she was scared for my safety. But the most important thing to her was for me to be happy and healthy."

Do lots of straight men accidentally hit on him? "Story of my life! Never really gay men. I think I was always too feminine." How do heterosexual men react when they realise he is a man? "A lot are shocked. They're never aggressive and a good percentage are even more interested." Do girls fancy him? "Yeah. I definitely get both sides."

He thinks of himself neither as gay nor straight. "For me, love has no boundaries. I'm not an extremely sexual person, but I am romantic." He doesn't object to the word transgender, but says it isn't accurate – he has no desire to be a woman. Androgynous, he says, best sums it up. "I'm pretty happy with how I am now." When Pejic was growing up, David Bowie was an influence, as were British new romantics such as Boy George and Pete Burns. Pejic turned down a place at law school to pursue modelling. At some point he hopes to take up law again.

In the two years he has been modelling, Pejic has created his own niche – he can model as man, woman or nonspecific. He was discovered when working at McDonald's. Did the agent think he was a man or woman? "I don't know – he never said." Although the Australian agency signed Pejic, they had trouble convincing others there was a future for him. "All these agencies in London said no because they didn't know how to market me. I was too feminine for menswear, but there was never a boy who had made a lot of money doing womenswear, so it was a financial thing. I still have to prove myself to be commercially viable."

It was in Paris that his career took off, when he worked in both men's and women's shows for Jean Paul Gaultier and in the men's shows for Marc Jacobs. "That's when I got a huge amount of recognition. It was very high end. The downside was I'd never make a lot of money from it, but the plus was I got more media attention." Pejic is currently ranked 18 on models.com's top 50 male models list.

Does he prefer women's or men's clothes? "Women's clothes are less restrictive; I definitely have more fun with womenswear."

How would he describe himself to somebody who's never seen him before? "A hot tall blond!" he says with a giggle.

What makes a good model, and whom do you admire?

Somebody who just lets go and becomes a canvas for art or fashion. I admire Kristen McMenamy.

What have you eaten today?

Cereal, then a pumpkin sandwich for lunch and sushi for tea. To maintain a 25-inch waist, you can't go round eating cakes and chocolate.

What was your worst job?

I was working in Finland on a nature shoot in a swamp, and I fell in the water and really hurt myself. We kept on shooting, and I later discovered I'd fractured a rib.

What is the worst thing anybody has said to you?

I'm not easily offended.

Would you recommend modelling to your children?

If I think they could do it, yes.

Who is your favourite designer?

Alexander McQueen and Thierry Mugler.

• Interview by Simon Hattenstone

The black model: Jourdan Dunn

Jourdan Dunn: 'There are loads of new black faces on the runways.' Photograph: Camera Press

When Jourdan Dunn was 16, she and some friends were in Primark, mucking around trying on sunglasses, when Dunn noticed a woman staring. "She kept looking at us, and I got a bit paranoid that she thought we were going to steal them. But then she asked if I'd ever thought about modelling." The scout gave Dunn a card and told her to call her agency. "It was Storm and I knew they represented Kate Moss. As soon as she'd gone, I called my mum. I was screaming. She was screaming. I couldn't believe it."

That was six years ago, and today Dunn is an established cover girl, catwalk star and face of Burberry. When we speak, she's in the middle of Milan fashion week. Today she did a Fendi show, had a casting and two fittings. "It was pretty chilled – sometimes I finish at midnight and have a 6am call the next morning."

As one of the few black supermodels, Dunn is pleased to see more models of colour at the shows these days. "There are loads of new black faces on the runways, which is a great thing. When I started out, it was different. I did experience some issues with the colour of my skin – I used to get a list of castings and there would be notes saying they just wanted blondes. I think hair and make-up played a part – obviously, black hair and skin are different, and some stylists don't know what to do with it. Maybe they're scared it won't look good." As she was about to go into one casting, her agent called and said, "Turn back – they decided they don't want any black models."

But Dunn had a breakthrough in 2008 when she became the first black model to walk a Prada runway in more than a decade. "I was really nervous because everyone was hyping it, but Prada are famous for pulling you out of shows at the last minute, so backstage I was waiting for them to tap me on the shoulder and tell me I wasn't going on. On the runway I wasn't thinking about following in Naomi's footsteps, I was thinking about not falling over."

That year the teenager from Ealing also made the cover of the historic "black issue" of Italian Vogue, shot by Steven Meisel, alongside Naomi Campbell and Tyra Banks. Does she resent such special treatment? "I understand the arguments against, but I think it was a step forward. After that, you did see more black models in Vogue."

Still, she concedes, there seemed to be a belief in the industry that there was room for only one black face at the top, an idea that almost ended her friendship with fellow supermodel Chanel Iman. "It was weird because, [in] my first season, she came up to me and said, 'It's really good seeing another black model doing good.' But then she had people in her ear, saying, 'Stay away from Jourdan, because she's trying to steal your spot', and I had people in my ear saying, 'Don't trust Chanel', and after a while we just stopped talking. We weren't horrible to each other, but we stopped telling each other what we'd been booked for."

But they became sick of being pitted against each other. "We just sat down and said, 'This is so stupid.' I hate it that people feel black models have to be nasty to each other."

In 2009, Dunn became pregnant. "I was thinking, 'This baby is going to ruin my career.' But then I thought, 'I want this baby. We're going to have to make it work.' "

Single motherhood didn't prove to be the career death she'd feared. In fact, when she was seven months pregnant, Jean Paul Gaultier cast her in his show. "He made a special look for me – a shield around my bump. Everyone had fake tattoos, and mine was 'Jourdan plus one'."

Her son is now two, and Dunn's mother looks after him when she's away working. Travelling, she says, is both the best and worst part of the job. "Being away from my son kills me, but I do get to go to amazing places. The other annoying things are the lack of sleep and the rubbish catering. I will scream if I see another sandwich. I'm a food lover. My family are Jamaican and I grew up in the kitchen. I am not a snacker, I like to have a proper meal, but at the shows I have to grab what I can."

Dunn says she's never been pressured by her agency to lose weight; if anything, it has been the other way around. "I am naturally thin. My dad was 6ft 5in and skinny as a stick, and I'm the same. But I find my metabolism annoying. I'd like a bit more weight on me."

What makes a good model, and whom do you admire?

Personality plays a much bigger role now than it did. Someone I'd look up to would be Naomi – she's a black girl from London, and so am I.

What have you eaten today?

For breakfast I had a couple of strawberries, a banana and a cup of tea. Lunch was a McChicken sandwich. After that, I had some chocolate. And in a minute I'm going for dinner – I'm looking forward to a nice steak and fries. I like an occasional glass of wine, though I don't drink before a shoot or a show – blotchy skin is not a good idea, however good your make-up artist.

What was your worst job?

It's not much fun standing around for hours in shoes that don't fit.

What is the worst thing anybody has said to you?

A make-up artist said, "I don't feel comfortable doing her make-up because I'm white and she's black." Then she started doing it anyway and I said, "I'd rather you didn't."

Would you recommend modelling to your children?

That's a tough one. If you're young and going around New York on your own, it can be really scary. It can damage you. Getting told at a young age that you're too skinny or have big hips could kill your self-esteem. So, no, not under 16. And I'd want to be there with them every minute.

Who is your favourite designer?

I love Burberry. I love their collection this season – I walked it and it's really wearable. The other designers I like are the same: Stella McCartney, Alexander McQueen, Alexander Wang, Isabel Marant.

• Interview by Liese Spencer

The plus-size model: Tara Lynn

Tara Lynn: 'It's been full-time all the way.' Photograph: Solve Sundsbo/Art + Commerce

When Tara Lynn walked into a modelling agency in Seattle on a whim four and a half years ago, they signed her on the spot. Of course they did – she is ridiculously, deliciously beautiful. But what makes someone who, at a UK size 16, had felt alienated by the fashion industry for years put themselves in a position where their body is going to be judged? Partly, Lynn needed the money while studying, but it also becomes clear, after speaking to her, that she is highly self-confident and feels that, while her size might not be considered "right" by the usual standards of the fashion industry, it is right for her.

After graduating in linguistics in 2009, Lynn was cast for influential style magazine V. "From there, it skyrocketed," she says. "And it's been full-time all the way."

By 2010 she was on the cover of Italian Vogue and last month she appeared on the cover of French Elle. Getting editorial work in style magazines – as opposed to commercial work – is still rare for a plus-size model, but Lynn thinks that's changing. "We're getting cast a little bit more and starting to see a diversified body image in shoots."

Lynn is 29, but looks much younger. Growing up, she says, "It was impossible not to look at magazines and look at my body and think, 'If only I was skinnier' or, 'If only my legs weren't so muscular.' Then, one day, I remember seeing this brunette, plus-sized model in a homecoming shoot. It was amazing. Seeing that one image during my adolescence was such a relief. I wish there had been more." The idea that young women might see a picture of her and be inspired to be more accepting of themselves is "so exciting", Lynn says.

During her teens, Lynn gained "a little too much weight. By then, I knew I was different from the magazine ideal and was never going to be as skinny or petite as my girlfriends. But I gained weight due to not eating a nutritious diet and not doing enough exercise. I remember feeling awful in my body, and it took until I was about 21 or 22 to take control of my habits."

At the time, she was living in France, working as an au pair. "The little girl I was watching came to me one day and said, 'The kids at my school make fun of you because you're fat, but I don't care because I love you anyway.' And she gave me a hug. I started crying, first of all because she was so sweet, but also because of what these children at school had said." She laughs. "When five-year-olds are hurting your feelings, you have to do something about it."

There was a period, a few years before Lynn became a model, when she was working out six days a week. "It wasn't grotesque, but my collarbones were visible, my hips were sticking out, you could see my ribs," she says. Even so, she was still a UK size 12: "I'm just made big." Now, she says, she eats well, exercises regularly (she likes to hike and do yoga) and has allowed her body to find its natural, healthy shape.

Has the fashion industry really changed its attitude to size? After the aesthetic for waiflike beauty took off in the 1990s, models got thinner and thinner, culminating in the size zero debate in 2006, prompted by the deaths of two models from anorexia. "It was terrible for our health, not just our body image," Lynn says. "It's such a normal part of human socialisation to measure ourselves against our peers, thinking, 'Do I fit into that?' But it's valuable to have diversity. We have to celebrate our bodies. There is no reason to hate what you live in – the only choice is to take care of it."

What makes a good model, and whom do you admire?

Adaptability and physical fitness. Lara Stone is lovely.

What have you eaten today?

I had a fresh detox juice for breakfast and a coffee. For lunch I went to a vegan cafe in Seattle called Plum and had a beet salad and a pumpkin and tofu crepe. I had a vegetarian arepa [a south American cornmeal patty] for dinner and a glass of Ardbeg whisky for a nightcap.

What is the worst thing anybody has said to you?

I remember one photographer saying, "Who did the casting for this?"

Would you recommend modelling to your children?

If they just wanted to be recognised for being pretty, then no. I hope my future children will not want to model. It's kind of a brutal industry.

Who is your favourite designer?

So little fits me! There are things that look good on other people, but I can't say it's my favourite because I don't get to wear it. I like Céline bags.

• Interview by Emine Saner