Has it helped you keep a model’s figure? I lost weight at once from not eating meat. That was because in my modelling days the regular diet was steak and grapefruit. Can you think of anything more constipating?

Calorie counter or anything goes? I never diet, but sometimes if I have a part coming up I may change my body shape. The Twenties writer Elinor Glyn, whom I play in The Cat’s Meow, was quite a bit heavier than I am. So leading up to the film I had three courses of everything and bread with every course. Rather than look nice, my first duty is to look like the person I am playing.

What’s your poison? When I am on my own I might smoke four or five cigarettes a day, which doesn’t seem a lot.

Ever tried to quit? I gave up once and felt shocking. I could hardly walk, I felt so tired. Cigarettes and coffee keep your energy levels up. If they are poisons, I think they are rather excellent.

From Purdey to Patsy, your look has often been described as iconic. Is it? Purdey came to town when everyone had rather long, floppy hair, so suddenly a rather short, small head was brand new, so it became a look. Patsy’s hair was iconic simply because of the gay following. Gays liked it because they could dress up like her quickly. And gay boys are often arbiters of new fashions, aren’t they?

Is the pressure on to look absolutely fabulous all the time? I have already disappointed a lot of people by driving a normal car and wearing rather dull clothes. When I went on a safari for TV a couple of years ago, most people knew me as Patsy, so they were quite surprised when I turned up looking normal.

So you don’t spend hours in front of the mirror? Tooth cleaning is about the only thing I do every day. I am allergic to a lot of things, so I just use Astral, as face cream, make-up remover, everything. It was funny, after using it for more than 25 years I was asked if I could do a commercial for it.

Would you ever give nature a helping hand? I see no reason why you shouldn’t change your face. But this is who I am. It’s no good me looking like someone completely different because I wouldn’t get any work. I have had collagen put in my frown marks. It’s so, so normal, just like dyeing my hair. If you have big tits, don’t wear them round your waist; wear a bra.

Green tea or your GP? I am vegetarian. I don’t get ill.

Pop any pills? I don’t take vitamins or supplements apart from Imedeen, which I buy from Boots. This is when I am not a good vegetarian because it’s full of the stuff I don’t usually eat — fish scales, fins, bones. I have taken two a day for 17 years and it is supposed to keep your skin free of wrinkles.

HRT or soya cake? When I was going through the change of life I was in a TV series called Class Act and I could not learn my lines — and I used to have a photographic memory. My GP said: “You want HRT.” That afternoon I was like Einstein.

Any traumas? Trying to look nice at charity balls. Trying to look nice is draining.

And finally, what’s the secret to being Joanna Lumley? Being adaptable. Not giving up. Part of my longevity is that I am interested in many things. That is my guiding principle.

Joanna Lumley is appearing in The Cat’s Meow, which opens in cinemas nationwide from June 4.

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