Editor-At-Large: The bonkathon for Mayor is an insult to struggling parents

Best joke of the week? It's a good job Ken didn't have 4 x4 – it could have proved very expensive! Even if the recent balmy weather has temporarily been replaced by a cold snap, the testosterone levels of our politicians, like sap, seem to be rising by the day.

First, "waffling" Lib Dem leader Nick Clegg admits to Piers Morgan in a magazine interview that he might have slept with "no more than 30" women – demolishing his super-nice image overnight. Then, Ken Livingstone, fighting to be re-elected Mayor, tells BBC London news he has fathered no fewer than five children by three different women. And isn't married to any of them. Hold the front page!

Ken has always refused to comment on his private life, threatening to sue journalists who sought to print stories alleging that he had fathered a son 15 years ago. Now, as a book about his life is to be serialised, he's come clean in the hope of damage limitation.

What politicians get up to in their private life is their own affair, and there's no evidence that Ken is a bad dad. But I do find the news that despite his extended family being spread out he claims he is an "involved" father rich when he bangs on about children needing a moral code and blames bad parenting for the rise in teenage violence in London. For Ken, finding quality time for all his kids, who range in age from "girls" in their 30s to small toddlers, must be fiendishly difficult. Ken will be admired in some quarters – the trendy left, for example – for saying there is a difference between what is private and what is secret, claiming that everyone in his close circle knew about his offspring. Compared with blabbermouth Clegg, he seems almost discreet.

I wonder, though, how the women fared. Were they left behind to bring up these kids by themselves? How did they feel about him? They have never said anything in public, but now Livingstone has gone public they must be fearing unwelcome media intrusion into their lives. They have been sacrificed on the altar of his ambition.

The election for Mayor of London is turning into a bonkathon. Boris Johnson's extended extramarital affair with journalist Petronella Wyatt was documented (including the fact that she had an abortion) in a biography by Andrew Gimson, and tabloids have hinted at other bits of friskiness over the years. When I interviewed him recently he was valiantly clamping down on any mention of his kids, his former drug-taking, his affairs and his verbal indiscretions, attempting to rebrand himself as a committed future leader. The Lib Dem candidate, Brian Paddick, has already faced the embarrassment of having a former lover sell his story to a newspaper and make all sorts of ghastly allegations.

A string of MPs, from David Blunkett to Tim Yeo to Stephen Byers, has fathered babies out of marriage, so we don't expect politicians to set a moral example. Both Clare Short and Ann Keen have been reunited with babies they gave up for adoption when they were teenage mums.

The people who do seem to be judged poor parents, how- ever, won't be middle-class Ken or smoothie-chops Robert Kilroy-Silk, but sad Karen Matthews, who, as the tabloids remind us daily, has had seven kids by five different men, and whose most recent partner, 22-year-old fishmonger Craig Meehan, is spending this weekend in police custody for his own protection. He has been charged after 130 indecent images of children were found on two computers at the home they shared in Dewsbury, West Yorkshire.

Karen's daughter, Shannon, was found at a relative of Craig's house after 24 days. Karen is now staying at a safe house, said to be near to breaking point. I've never had much doubt that Karen is a decent mum being subjected to trial by the media for the crime of being poor, white and working class. Ken Livingstone, on the other hand, and to an extent Boris Johnson, can preen as much as they like in public, and claim they are excellent parents. I find their hypocrisy nauseating.

Less than model behaviour, Naomi – again

I have banned myself from Heathrow for the past two years. I haven't got the temperament to deal with the queues, delays, cancellations and lost bags. Now there is also the nightmare of Terminal 5. BA has admitted that cancelling flights and losing 30,000 bags has cost it at least £16m, as well as quite a few customers.

The troubled airline must have thought it was beginning to get back to normal by the end of last week, but they hadn't reckoned on the passenger from hell, Naomi Campbell, who chose to fly from Terminal 5 to Los Angeles. When one of her bags didn't arrive at the plane, she allegedly threw one of her famous "tantrums". I can't help feeling sorry for Naomi – it's as if everyone expects her to lose her rag. This time she was taken off the plane in handcuffs, arrested on suspicion of assaulting a police officer, and released after almost seven hours. Take my advice, Naomi: if you must fly, try Manchester, or London City airport to go via Paris or Schipol.

The water myth is all washed up at last

I'm thrilled that another beauty myth has been laid to rest. This time it is the notion that we need to drink at least eight glasses of water every day to avoid being dehydrated and to flush out apparent evil toxins from our systems.

This ridiculous notion has long been propounded by beauty journalists, who intone it like a modern mantra for healthy living. It has produced tribes of women who wander around clutching mini plastic bottles of water as though they are traversing the Sahara desert and not a station forecourt in Wolverhampton or a supermarket car park in north London.

Scientists have found that people who live in hot climates and athletes do need to drink more water. But most of us will not benefit from constantly swigging the stuff, rather than tea or coffee, to make up the 2.5 litres of liquid we need a day. And as for flushing out toxins – which I never believed existed anyway: too much water can actually interfere with kidney function.

Another myth debunked is that drinking water somehow hydrates your skin and will make it feel moist. Scientists say that this is pure codswallop.

Women are constantly bombarded with phoney information dreamed up by nutritionists and diet experts. Only the other week another bunch of scientists laid to rest the myth of "superfoods".

When will women have the courage to eat and drink what they want – in moderation– and feel happy rather than anxious?