After a difficult childhood, Mariah Carey, 37, began her musical career in her late teens. Her big break came when her demo tape was given to Tommy Mottola, then the head of Sony Music Entertainment. They married in 1993, and divorced five years later. She is the bestselling female artist in history, with record sales of more than 165 million worldwide. She has won five Grammy Awards and is the world’s richest female recording artist. Despite what she calls the “debacle” of her debut film, Glitter, she is shooting Tennessee in Albuquerque, New Mexico, with Lee Daniels, who produced Monster’s Ball. She flew to London this week to promote Pinko, a high-end, high-street label with which she fell in love after visiting its store in Capri.

You’re rumoured to have a serious walk-in closet.

I have four if you include storage. I live on three floors of a block in Tribeca, so I have space. There’s one for lingerie, a shoe closet I designed with the architect Mario Buatta, and a pretty area for clothes with moving wardrobes and a bunch of shelves where I do fittings with stylists. The closets are a big part of my life, but it’s a work environment, too. It sounds obsessive — and it is pretty fabulous. But when I was 17 I had to wear my mum’s shoes and my feet poked through them. It was a really snowy winter and I thought, “One day I’m going to have so many shoes”. The money thing was weird, like I went to bed poor and woke up rich.

How do you accentuate your best features?

I’m not sure I have best features. I had things I hated about myself. But I always believed in my voice and my music writing. At the start, I was offered $5,000 for my music rights and that was a fortune to me, but I knew enough about the business and my talent not to accept it. I would have ended up with nothing.

Worst fashion looks?

At the age of 12 I dyed my hair orange by mistake, and I shaved my eyebrows. You get a complex from that.

How much pressure does the industry put on everyone to look the same?

The industry doesn’t really know what it wants until it sees something successful and then tries to carbon-copy it. At the start of my career I didn’t see it as being about style; it was about talent. My mum was an opera singer and I'm privileged to have sung with Pavarotti. I hang out with a lot of singers and musicians — who aren’t size zero, so my body image is not part of that world.

What was with all the raunch?

People always said that I was raunchy, but how can I be raunchy? I’m eternally 12. The photographer David LaChapelle says I look like Mary Poppins. At the start I deliberately didn’t do bare midriffs because I wanted people to concentrate on my voice. I was being advised by people well into their forties on what was cool, and they wanted me to be wholesome and All-American, which I’m so not. My father’s black, my mother’s Irish-American, and the way I grew up was hardly The Brady Bunch .

But once they got the voice, I really had to push to wear things that were more revealing. It was probably because I was rebelling — I was married young and my husband was very specific about my look. I couldn’t even do my hair the way I wanted because he wanted it his way. I cannot believe now that I was married. When we got divorced I just wanted to have some fun.

Do you regret any outfit?

Many, oh so many. But if I tell you which ones, you’re gonna run them huge, right?

Hot date: what do you wear?

I haven’t really gone on many, believe it or not. But I’ll wear whatever I think is sexy — it doesn’t mean that I’m going to bed with that person.

High maintenance?

Completely. Everything about me is high maintenance, starting with the voice, which I look after like a child. I take a humidifier wherever I go and I sleep in a steam room to protect it. The TV in there is behind glass.

Then there’s the body, and my trainer, who is about the size of my pinkie finger, but she understands my body. I’m very muscular, so if I wear a wrong-shaped dress, people always think that I’ve gained weight. Actually I’ve stopped weighing myself. I’ve got thighs and buttocks and I’m never going to be a size zero. I like my curves. But I'm not gonna lie — if there’s a sample that’s a size two and I fit into it, I feel great. I don’t do enough gym. I don’t do facials because I have rosacea and having people poke at your face is not good for that. But I have home remedies: I make little packs of milk and ice to calm it down. I’m a beauty school dropout. I did 500 hours, so I can do my own make-up and hair. Now the hair is high maintenance. It’s really curly and can take hours.

Favourite designers?

That’s difficult. It’s more about favourite pieces. Today I’m in Gucci [camel poncho] and Alexander McQueen [but-ton-up black stiletto ankle boots] and these two rings from Van Cleef and Arpels [enormous diamond-encrust-ed butterflies, a tribute to her album Butterfly ]. It’s quite pared-down, mainly because I spilt something over myself and had to take off the blouse that I was wearing.

Is there anything you wouldn’t wear?

Flat shoes — they give me blisters. My babysitter used to laugh at me because when I was 12 I was always on tiptoe. I couldn’t walk flat. Even my trainer said to me, “Mariah, you canNOT wear flats” — and I’m like, but they’re Hermãs and they match my bikini. I guess I’m a heel girl. I can run in them. I could swim in them if necessary.

Would you ever contemplate cosmetic surgery?

I hope when I get to that stage there will be a cream. Botox? Well, we’re still not sure what’s in that stuff. I’m lucky — because of my ethnicity, I think that I’ll be able to live with the lines.

Are you for ageing gracefully or disgracefully?

What’s disgracefully?

I think ageing at all is just horrible.

Do you follow trends?

Not really, because I don’t read magazines — you see all these pictures of yourself getting bashed. My friends cut out the nice ones. I’m oblivious to the other stuff. The press has put me through the wringer, but at this point in my career, let’s be honest, it doesn’t really matter.

Pinko is available from Harrods, Harvey Nichols, Selfridges and its flagship store at 161 Brompton Road, London SW3.

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