There is a delightful photograph of my prepubescent siblings on the beach in Italy, sometime in the Seventies. In the frame, we occupy a scorching strip of grey sand. We are all wearing swimming costumes that bite into our milk-fed English flesh (in the case of the three boys, trunks, in my case an ill-advised bikini) and squinting towards the camera, holding up dripping ices like trophies.

Around us, also captured, are several groups of skinny ribby Italian children with concave stomachs and lean brown limbs. They are hooting and pointing with unconcealed derision towards us.

For the English family on bella figura beach looks like a newly whelped tangle of skinned albino elephant seal pups, all tummy rolls and dimpled white thighs.

So it is nice to find out, so many years later, that scientists have discovered a gene that contributes to obesity, known as FTO, which is endemic to these shores. “We live in a blame culture in which when people gain weight it is entirely their fault,” said Professor Graham Hitman of the London Queen Mary’s School of Medicine and Dentistry of his discovery.

So I could look at this photo and whimper: “It was only because we had the fat gene. We were born to be fat. It wasn’t our fault.” I could, but that would be ignoring what the prof went on to say. “This exciting research confirms that while improving lifestyle is key, some people will find it harder to change their weight than others.”

Oh. So we are back to what we always knew, then?

My siblings and I did — as is all too obvious — have the fat gene. But the other, bigger reason we were blubbery then was because we ate cheese on toast a lot and lay around reading Just William, resisting calls to go for walks or to gather firewood, only rising from the horizontal to exchange blows with each other in a long-running, violent dispute over whose turn it was to sleep in an orange camp bed that my middle brother had peed in.

I remember going out to lunch with my parents and worrying not whether there would be strange foreign food, but whether there would be second helpings. I remember the Belgian doctor telling my mother to only allow us skimmed milk. I may have had the fat gene, but I was also greedy. So when you add greed to someone who is already predisposed to the adipose you get a fatty, or someone who would be Bunterish if they don’t watch their calorie intake and exercise output like a hawk, as I admit I have to (my brothers are muscled, godlike creatures as adults, meanwhile). It’s not fair. But then what is?

It was obvious to me then, on the beach, aged eight, as it is obvious to me now: there are skinny families and fatty families, and it’s heavily influenced by genetics into which camp your one falls.

You can gnash your teeth all you like about the rail-thin rakes who claim not to be able to put on weight, who pack away bread and butter pudding and chips like there’s no tomorrow, the postpartum bikini-ready models who trill that the pounds just fell off “running around after their toddler”, but I think they are speaking the truth. And they probably prefer salad.

All that stuff about “heavy bones” and “slow metabolisms” and “a lifetime on the hips” has been to some extent confirmed, even though the main cause of obesity is, as the scientists remind us, the syndrome known as “food retention”.

And it’s not great news for most of us. The reality is, fat is the qualifier in modern society. When we were a hunter-gatherer society, having the fat gene was an advantage because the ability to store fat could help you survive famine. Now it is a curse.

Apart from people such as Beth Ditto and Dawn French, who are quite wonderful and spirit lifting in every respect, basically the writ runs: if you’re fat you’re a loser, if you’re thin you’re a winner.

Some lucky people are born thin and can eat what they like without it making the slightest difference (call them ectomorphs) others less fortunate than them can eat three raisins and worry about gaining a stone (let us call them Liz Hurleys).

The fact that scientists have now discovered a gene confirming that our DNA divides us into winners and losers before birth does not make this better or fairer. It makes it worse.

- When British sailors cry, the Americans say it reminds them of Princess Diana’s funeral and the French say it makes us seem girlie and American.

“It seemed that Brits, once a tough-minded nation marked by self-control, had been transformed into touchy-feely devotees of a loose and self-forgiving emotionalism,” was the verdict of the Chicago Sun Times.

“Has there been an Americanisation of British troops?” asks the commentator Dominique Moïsi from Paris.

Americanisation (if that is what we are witnessing) is no longer confined to our frontline forces, though. In the even scarier theatre of war that is the British classroom, teachers have also been issued with the book of Barney.

They have been told to send good news postcards to the homes of their worst performing pupils rather than bulletins of bad behaviour and visibly ovulate with excitement if a truant turns up to class, no doubt chanting: “I love you, you love me, we’re a happy family.”

Now I can quite see why the educational authorities in despair have turned to the repetitive, endlessly positive philosophy of the cuddly purple dinosaur and are deploying on feral teens the same subtle logic that rewards the unhouse-trained puppy for pooping outdoors.

It is obviously the fond hope that the Good Boy Choc Drop or the lashings of undeserved praise will so positively and productively reinforce the good behaviour that the puppy/pupil will ditch the bad.

But something does not feel, shall we say, right about this. It was not until I read General Sir Michael Rose on all this last week that it all clicked into place and confirmed in my mind doubts that what might work in the home and in kennels cannot work in the army or in the school.

“The commanding officer used to be a feared and respected figure,” he said. “Now, as soon as he makes some disciplinary judgment, it can be overridden by civilians. So the soldiers have become disorientated. The modern approach of society, with the emphasis on rights, has now been imported into the military — and with disastrous results.”

Substitute teacher for commanding officer, civilians with parents, soldiers with pupils, and the military with school in the above sentence and the lesson becomes apparent.

rachel.johnson@sunday-times.co.uk

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