What DO the singer the bishop and John Humphrys get up to underneath the duvet?

Our grannies may tell us that we need less sleep as we get older - but it seems they are wrong.

Apparently, as we age, we cope better with our sleep being interrupted, but our need for shut-eye never diminishes.

We asked some of Britain"s most successful writers, thinkers, politicians and personalities about their bedtime habits ...

Sweet dreams: Our need to sleep does not diminish with age

6 hours: Carol Vorderman

CAROL VORDERMAN, 49, TV personality

My idea of heaven is grabbing an hour"s nap in the afternoon - but, sadly, that happens only about once a year.

My ideal seven-hours-a-night went out the window when I became a mum. Today, I"m lucky to get six.

I try to get to sleep before midnight, then I"m up at 6am for the school runs. I could happily survive on that amount of sleep if I never touched alcohol, but when I do have a drink during the week I feel the full effects of my busy lifestyle.

I find summer the hardest, as I"m very sensitive to light. I"m awake at 5am even if the curtains are closed. I"m not a dreamer and I certainly don"t believe any of that rubbish about interpreting dreams.

For me, waking up is done with purpose during the week. I"m straight up with an alarm and out of bed. But at the weekends, my ultimate treat is breakfast in bed.

6 hours: Clive Anderson

CLIVE ANDERSON, 57, TV presenter

I can get by on very little sleep, and frequently do. This can be very useful if I have a writing deadline to meet, but usually it just means that I have more time to fritter away during the day! I seldom get to bed before 1am, but I can stay up much later if the occasion demands.

I quite often have dreams, but I don"t think that dreams are particularly interesting to anyone other than the dreamer. I wake myself up at 7am and listen to the Today programme: it"s very invigorating to hear John Humphrys laying into some hapless minister before breakfast.

My body clock usually wakes me up - but failing that my wife gives me a jolly good nudge.

8 hours: Fiona Fullerton

FIONA FULLERTON 53, former actress turned writer

I dream a lot, and my most recurring dream is a throwback to when I was an actress. I"m in a musical or show and I"m not prepared. I haven"t had enough time to learn the words, my costume doesn"t fit and I can"t find the stage.

I haven"t been on the stage for 15 years, so I think it must just be anxiety-related. When I was younger, I used to be able to go out partying and go to work the next day, but now I need nine hours" sleep a night - though I usually get eight due to my early start.

I"m in bed by 10pm, but have to be up at 6am to take my daughter Lucy, who"s 14, to school in Cheltenham at 7am. It"s very different to when I was an actress and would either have very early starts for filming or late ones for the theatre.

I wake every day to music on the radio - Classic FM or Radio 2. It"s always such chaos in the morning, but music eases me into the day. It"s less severe than an alarm clock.

9 hours: Jeanette Winterson

JEANETTE WINTERSON, 50, novelist

When I come to London, I sleep far too little and turn into a grumpyperson. If I lived in London all the time, I would be a wreck. I needat least nine hours" sleep, always.

When I am at home in the country, I go to bed at 11pm and get up at8am - unless it is Sunday, when I go back to bed and relax with a book.I am a seasonal creature, as I live primarily in the country.

Insummer, I have a different routine: I get up at 7am and go to bed atmidnight, but sleep in the afternoon for a couple of hours. The onlything that wakes me during the night is my cat - not even my girlfriendhas a chance of waking me.

I always dream. I love mydreams, but I can"t always remember them. I never use a clock, butwithout fail I wake within five minutes of the summer or winter hour. Ican rely on my body clock.

7 hours: John Humphries

JOHN HUMPHRYS, 66, Radio 4"s Today programme presenter

My recurring nightmare is that one day every politician will answerevery question totally frankly and honestly - and I"ll be out of a job!I do dream, and I have the occasional nightmare.

If I ampresenting the Today programme, then I am in bed by 9pm. My body hasgot so used to this that 11pm feels very late. I like to get at leastseven hours" sleep a night. I am up at 4am when I am presenting.

IfI"m not, then I wake between 6 and 7am. I"m a very light sleeper andthe slightest noise will wake me, but I live in a very quiet square, sothat"s not a problem. I wake to the radio, but I am toying with one ofthose alarms that light up gradually to make you think dawn hasarrived.

I"m very good at cat-napping. Half an hour after lunch, or even 20 minutes, is very restorative and good for the brain, too.

6 hours: Alain De Botton

ALAIN DE BOTTON, 41, philosopher and writer

I need at least eight hours" sleep but rarely get more than six, due to having young children and an anxious temperament.

I go to bed every night precisely at 11.40pm and wake every morning at 5.50am. My routines are extremely precise.

Unfortunately, my capacity to think is hugely dependent on how much sleep I have had, so at night I"m often nervous.

I lie in bed worrying about sleep, and that stops me sleeping. When I do drop off, I am often woken by my youngest son, who is three, for whom the night is just another period of day for him to continue to explore.

When I am finally asleep, I have wonderful fantasy dreams: enemies who meet a sticky end, alienated friends with whom I"m reunited, misunderstandings cleared up.

I have some nightmares, too, usually involving - of course - not having revised for my Cambridge History Tripos exams. I now regularly go back to bed at about 9am if I still feel tired, which makes me feel very, very guilty.

4-5 hours: David Starkey

DAVID STARKEY, 65, historian

If I am filming or performing in public, then I can get by with very little sleep indeed - between four and five hours.

I wake very early, at about 5am, then go out filming all morning. Then I"ll have a few glasses of wine at lunchtime, go back to bed and sleep for two or three hours, before getting up to work all night.

If I am writing, I go to bed about midnight then invariably wake at about 4am. I find that writing is a continuous thought process, and it"s very hard to switch off your brain. So I get up and potter about. I make a cup of strong camomile tea, and either sit and think - I have some of my best ideas at this time in the morning - or make some notes.

Then I go back to bed and can sleep until eleven. I rarely remember my dreams. My only nightmare is about losing my luggage.

6 hours: Dr. John Sentamu

DR JOHN SENTAMU, 60, Archbishop of York

My days vary a lot - I am often in meetings in London - but I will be in bed no later than 11.15pm.

I believe in unwinding properly before going to sleep, but not by reading in bed. The only book at my bedside is my Bible, which my wife Margaret gave to me when I was 22 and we had just got engaged.

I usually sleep very well, but if I do wake up, then I know it is there. I get up early and go into utter silence for about 30 minutes, when I remember all the people who are waking up in pain or in prison.

More...What losing an hour"s sleep really does to your childrenThe great sleep myth: It ISN"T true we need less as we get older, say scientists

7 hours: Ann Widdecombe

ANN WIDDECOMBE, 63, Tory MP

I used to have a recurring nightmare: there was a nameless horror in the room and, try as I might, I could not switch on my bedside light. I had this nightmare for several years, and then, just as mysteriously as it arrived, it went.

I"ve never had the dream analysed, as I am far too hardheaded for that.

I need at least seven hours" sleep a night - less than that, and I am not at my best. I used to hate the all-night sittings in the House, and am sure this is to blame for the high death rate of elderly MPs.

I go to bed every night at about midnight, and read for half an hour to wind down. I nearly always wake at 7am, to my alarm. I am also a great advocate of the "cat-nap". I curl up on a sofa every day for half an hour for a snooze, and then my staff wake me.

5 hours: Jean-Christophe Novelli

JEAN-CHRISTOPHE NOVELLI, 48, chef

I"ve always survived on very little sleep. When I was a kid, I was hyperactive and would never sleep until very, very late. At 14, I started work as a baker, which meant working through the night.

Then the non-stop hours of a chef kicked in, so my sleep cycle has never been normal.

One problem is that I don"t switch off easily. I get so involved in my work that I can"t just go straight to bed. And I can only turn in for the day when everything is done.

Nowadays, if I get five hours of sleep, that"s enough for me. If I spend too long in bed, it actually makes me feel like a zombie.

The one thing that does wake me up in the night is my dogs. I have ten, and I"m sure that at least three of them are always awake, barking at rabbits in the garden.

What gets me up every morning is my stomach rumbling; and I can"t live without a cup of coffee first thing.

4-6 hours: Diane Abbott

DIANE ABBOTT, 56, Labour MP

Farming Today on Radio Four at 5.45am is what gets me out of bed in the morning. I have been listening to it for years and I find it very calming - perhaps because it"s somewhat removed from my urban life in Hackney.

Sleep is a precious commodity for me. When I get enough sleep I feel great - so much better. But the demands of my job mean that I usually only get between four and six hours in bed, when I think I need eight.

Not surprisingly, when I do sleep it"s very soundly. I nod off quite easily anywhere at all. I have been known to catch 40 winks in my office.

6-8 hours: Shami Chakrabarti

SHAMI CHAKRABARTI, 41, director of human rights charity Liberty

I am embarrassed to admit that my husband and I have a TV in our bedroom, and when we go to bed at about 11pm we watch something fluffy, like Glee or ER.

I ought to say I watch a programme like Newsnight, but when you have been dealing with serious issues all day, then you want something light and entertaining.

I"d love to be one of those people who can get by on very little sleep, but I need between six and eight hours. I am blessed in that I am a good sleeper, as is my son. He slept through the night from eight weeks, which was fantastic.

I have wonderful, creative dreams which take reality and blur it around the edges.

We all get up between 6am and 6.30am, have breakfast together and then leave the house precisely at 7.50am.

7 hours: Aggie Mackenzie

AGGIE MacKENZIE, 54, TV presenter and author

I am going on a run for Sports Relief in March, and I"m terrified, so at the moment I"m up at 7.10am every day to run a mile around the local park.

I"m not very strict with bedtime, but I do like to be in bed by midnight, so I can get a good seven hours before my alarm forces me awake. I sleep soundly and tend to dream - and the ones I remember are very odd.

I dreamt last week about being driven past a tearoom where everything in it was blue and purple. There were old women sitting outside eating blue ice cream, but when I stopped to ask for some, they gave me a pink cone. I was really annoyed. Maybe I need a dreams analyst.

HOW TO GET A GOOD NIGHT"S SHUT EYE...

Kevin Morgan is professor of gerontology at Loughborough University"s Sleep Research Unit. He says:

Each of us needs an amount of sleep that refreshes and allows us to take on the day. If youre in the 10 per cent of Britons who have shallow, fragile or unpredictable sleep, try these three tips.

Go to bed when you"re sleepy. Often those with trouble sleeping spend more time in bed than most. Aim to spend as little time awake, in bed, as possible.Never try to fall asleep. Sleeping is an automatic psychological task, like walking. If you have ever tried to think about walking down stairs, it"s normally a sure way to trip over. So try not to over-think it.The guardian of good sleep is regularity. Regularity in the time you go to bed and get up and the amount of exercise you take, as well as your diet. It won"t make you very exciting, but it"s worth it. Wake yourself in the same way, on time, each day in whatever way works be it a blaring alarm, a gentle nudge or your children jumping on the bed.

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