She is the minister called Supernanny for her ceaseless struggles to promote sensible drinking, ban smoking and cut teenage pregnancies. For her efforts, however, Caroline Flint has endured some of the most vicious personal abuse thrown at any politician since Margaret Thatcher.

“Self-righteous,” Claire Fox wrote in The Times. “Goody two-shoes,” (Virginia Blackburn, Daily Express). “(Barely) human football rattle” (Rowan Pelling, Independent on Sunday).

Why does the Public Health Minister care so zealously about saving the British from their own excesses, fearless of the hostility she breeds? A glimpse into her past may explain.

On alcohol, Ms Flint has roused fierce reactions. She has gone farther than any previous minister to champion the cause of sensible drinking.

She insists on better labelling so that drinkers can judge the strength of wines and beers by counting their units. But her support for labels that tell pregnant women and those trying to conceive to avoid alcohol altogether provoked a backlash. Even the Royal College of Midwives was moved to say there was nothing wrong with the odd drink in pregnancy.

And her proposal that middle-class wine drinkers should moderate their intake was, for many, the final straw.

Boris Johnson, the Conservative education spokesman, was typically scathing. “She is a junior minister anxious to make a name for herself and she has seen that there could be no more powerful way of asserting her own existence than stamping her mark, like the signature of Baron Philippe de Rothschild, on every bottle we buy. It is all about Caroline Flint, and it has very little to do with the drinkers of Britain and their problems,” he wrote.

Yet perhaps the minister’s true motives were rather more honourable. Ms Flint shed light on her difficult formative years in an interview when she became an MP for The House Magazine, Parliament’s journal.

“My mother Wendy died tragically at the age of 45, when I was 28 which was hard to deal with,” she said.

The Times has obtained a copy of her mother’s death certificate which spelled out the causes: “Lobar pneumonia due to alcoholic fatty infiltration of liver.” Alcoholic fatty infiltration of the liver is generally associated with excessive drinking.

Ms Flint went on to tell the magazine: “My mother Wendy had me when she was a 17-year-old in 1961. For the first few years of my life I was brought up by my mother and my grandparents, who ran a pub.”

The future minister entered the world at 12 Avenue Road, a mother-and-baby home near Regents Park helping to care for unmarried mums. Its address still pops up on internet messages from adopted children trying to trace their real mothers. A few days after Caroline Flint’s birth another baby, Princess Lavinia Marie of Yugoslavia, was born out of wedlock there. The royal child would go on to be adopted by her natural parents.

There were no silver spoons for Caroline. But nor would her young mother hand her over for strangers to adopt. Wendy Beasley brought her daughter back to the Jolly Blacksmith Hotel in Twickenham. The child’s nappies were changed amid the bustle of a pub serving a working-class area. Later, as an A-level student, she would earn pocket money working in the same pub. “My grandparents had long since gone but I met regulars who remembered me as a toddler.”

The girl born to a teenage typist has breathed new life into the Government’s commitment to halve pregnancies among under-18s. She hammered home the message by launching the sexiest-ever public information films, aimed at shocking young people into safe sex by warning of the risk of disease. And she helped to announce a VAT reduction on over-the-counter birth control such as condoms and morning-after pills.

When her mother was 19, she married Peter Flint, 25, a machinist’s son who was working as a television service manager, at All Saints’ Church, Twickenham.

A daughter, Andrea, was born in 1965 and Mr Flint adopted Caroline formally. By the time a son, Stuart, was born in 1969, Mr Flint had been promoted to be the TV company’s area manager.

“I did not know he wasn’t my biological father until I was about 10 — I had no reason to believe otherwise. It was not something the family talked about outside the home,” she told the magazine. “Only when I became older did I realise how difficult it must have been for my mother. I have never contemplated looking for my father and I don’t even know if he knows of my existence.”

Her parents split up when she was 13 and, in 1986, Mr Flint married a much younger woman. Caroline Flint leaves her adoptive father out of her entries in Who’s Who and Debrett’s People of Today. As a young MP, she shone on the committee examining the Adoption Bill, though few would realise her dedication might be informed by having gone through the process herself.

She sealed her image as a bossy nanny when she said that children should dance to improve their physical fitness and psychological health. Dance was an early passion. Although not well-to-do, the late Mrs Flint ensured her daughters did not miss out. Their dance teacher was Babette Palmer, whose most famous past pupil is her daughter, the child song-and-dance star Bonnie Langford. “If I could sing,” Ms Flint said, “I think I would have wanted to be a performer.”

Babette, who now uses her grown-up daughter’s surname, can still find Caroline Flint’s name in class books from the early 1970s. “She was a Tuesday child,” Mrs Langford says. “They did ballet, tap and jazz — it was then called modern. They both did an item with Anita Harris in The Good Old Days at Richmond Theatre.”

She is a member of the Division Belles, a troupe of dancing women MPs, although what sticks in the memory of one who has seen them is “a fixed kind of smile, as is she wasn’t enjoying herself”.

During Labour’s turbulent 1980s, Caroline Flint helped to run a faction opposing militants: “I’m tough and I don’t flinch from fighting for something I believe in.” She entered Parliament in 1997.

What next? She looks obvious Cabinet material, one of the few young female Labour MPs seen as ready to run a department, provided she can overcome that Supernanny label. Her great legacy will be the smoking ban coming into force next Sunday.

Support for Supernanny has come from an unlikely quarter: brewers and publicans on the front line of smoking and drinking reforms. Their leaders were delighted to meet a minister experienced in the pub trade. “She talks about drawing a pint when she was younger,” said Rob Hayward, chief executive of the British Beer and Pub Association and a former Tory MP. “She is actually quite shy about playing that card but when she spoke to us about banning smoking, she could well understand the difficulties.”

A theme runs through her policies on alcohol, pregnancy, fitness and sexual diseases. “Flintism” is about empowering people by alerting them to risks but giving them choices.

As she once said: “Knowledge is power and knowing how to make the right choices for yourself is how you get the best out of life. I have been lucky — but it was a bit hit-and-miss.”

Much has changed in Ms Flint’s world. The Jolly Blacksmith is now a gastropub, the Old Goat. Her mother-and-baby home has been turned into luxury flats. But she is still dancing.

CV

Born September 20, 1961, 12 Avenue Road, St John’s Wood, London

Education Twickenham County School for Girls; University of East Anglia (BA American literature and history with film)

Work Local government officer, senior researcher/political officer GMB union

Politics Joined Labour Party at 17. Labour Student National Women’s Office 1982-84; Labour Coordinating Committee executive 1984-85

Elected MP for Don Valley since 1997

Government Home Office Minister from 2005; Public Health Minister since 2005

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