You're starring in a drama celebrating 100 years of Mills & Boon. Do you enjoy a racy read?

I recently picked up a Mills & Boon. Ooh! I felt quite embarrassed! I started reading it and I have nothing against them, but they're not my cup of tea.

Not an old romantic then?

Oh, God, I certainly am. I love a bit of cheese! I love knowing exactly how people feel about each other, from my boyfriend to my mates.

Man in your life?

Yes. We've made a pact to go wherever the other one goes. He's American, so I have a strong connection with the States. My dream is to live in New York.

New York? That's a bit of departure from your good, solid Yorkshire background.

It certainly would be. We enjoy things in Yorkshire. There was always a bottle of wine on the table and two courses; a main and a pud.

Do you have to watch what you eat?

I don't feel the need to be skinny. I'm lucky because I'm always tearing around, so I can pretty much eat what I want. I never feel bad because I feel fat; I feel bad because I feel unfit.

Quite sporty then?

I love sport. I feel a pressure to maintain a certain level of fitness because I've always been fit. I'm an all or nothing person - I ran a marathon last year. I was at the peak of my fitness and rewarded myself with four months off. The kind of bodies I like on women are toned and muscular rather than emaciated.

Any fitness secrets?

When I go running, I pretend that I'm running away from people or that I'm carrying a life-saving medicine in a film!

So, yoga doesn't do it for you?

I feel better doing an aggressive sport. I like the pain of doing sit-ups, running, and punching. If you're not sweating and wanting to cry, it's pointless.

Not a girlie girl?

I really like clothes, heels and perfume, but if you punched me, I'd punch you back. I'd cry, but I'd do it. I don't preen. I don't do fake tan. I don't know how to make the most of what I've got like some people.

Wearing a corset in Consuming Passion must have been interesting.

It was amazing doing period work. The costumes were fantastic. They change your posture, and even the way you breathe. You're restricted in your movements, so you're forced to slow down and be elegant. That goes double for me, because I'm so manic normally!

So I guess you wouldn't consider having plastic surgery?

If I was going to do it, I'd have a nose job. I've got a kind of baby nose that never grew into an adult's nose. But I wouldn't because when I have kids, if they have my nose, I'd hate them to think that I don't think they're beautiful enough.

Any vices?

Wine. I could drink two bottles a night, but I would just pickle! I've never smoked. I have to smoke for films sometimes and I smoke like a teenager without inhaling - you can tell! I'm not cool enough to pull it off.

Green tea or your GP?

I get terrible migraines and when I'm suffering, I just want something to knock me out. If I'm ill, I use antibiotics, but would try something alternative if I was sick for an extended period. I've had reiki. The therapist doesn't touch you, but runs his or her hands over your body to realign your chakras. I was so cynical, but it was the most amazing thing. I can be quite manic and my brain sometimes feels like a ping-pong ball bouncing around. Reiki calmed me down for a couple of months.

Venus, your first film, was with the acting legends Vanessa Redgrave and Peter O'Toole. How do you stay grounded?

I still live in the same flat that I was in at college and I am mates with the same people. They would tell me straight away if I started acting like a dickhead.

Do you suffer from stage fright?

Yes, but in a fantastic way. I've never found it debilitating. I played a lot of sport as a child and it's a similar rush of adrenalin that spurs you on.

Are you generally happy?

I can be quite stroppy and irrational. I feel like I spend most of the day saying “I'm really sorry”.

What gets your goat?

Lateness. If I'm ever late, I turn into a psycho! I just can't rationalise that it's fine. Even if I'm only 20 minutes late, I start breathing in a panicky way.

So what would you change about yourself?

I've got a chip on my shoulder about intelligence, a real fear of knowledge. I think I'm thick. I wish I had more belief in my academic side and I wish I was a lot less selfish. I'd love to be the sort of person who has an allotment where I grew my own food and that I didn't go to Starbucks.

INTERVIEW: HARRIET ADDISON

Consuming Passion: 100 years of Mills & Boon starts on BBC Four, tomorrow, 9pm

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