En route to babysit the youngest of my nieces and nephews, I always have to fight the urge to buy them sweets – a desire born, or so I tell myself, of the certain knowledge I’ll need to resort to bribery later (the aunt, unlike the parent, is not supposed to yell, and so must fall back on more dubious means in order to put an end to the evening’s festival of tower-building and tickling). In truth, though, far muddier forces are at play. Some small part of me still associates sugar very strongly with a certain kind of love. In my own childhood, after all, almost every visiting adult was connected in my mind to a particular sweet. My maternal granny came bearing Dairy Milk and Tavener’s spearmint chews; Granny Cooke was a great one for liquorice. At my sister’s house, I gaze on the sugar-free biscuits and yogurts I’m supposed to dispense, and feel just a tiny bit mean and joyless.

We all of us carry this kind of stuff around, and it’s one reason why a successful food policy is so hard to formulate. Ancient history will always lay siege to theory, and social class may play less of a role – or a more complex one – than the experts imagine. In 2018, I would mostly rather eat cheese than chocolate; my kitchen cupboards are loaded, to a parodic degree, with herbal tea and couscous. Yet here I am, confessing that, in the matter of small children, I’m no better than a drug dealer; that I want nothing more than for them to associate me with being blissed out on the contents of a small paper bag. Like most middle-class people, moreover, I have my blind spots. It wouldn’t even occur to me to add sugar to coffee, and I only drink Coca-Cola when extremely hungover (not often, these days). But some sugary things are just a bit classier than others, aren’t they? Honey, fruit juice and white wine all get a free pass.

Some anti-obesity campaigners are busy arguing that the new sugar tax, which applies to any soft drink containing more than 5g of sugar per 100ml, should now be extended to, among other items, the huge caramel lattes sold by high street coffee shops. It isn’t, of course, very hard to see why, even before you learn that some of these vat-sized drinks contain up to 25 teaspoons of sugar (there are about seven in a 330ml can of regular Coke). For one thing, it’s a tax that has indisputably worked so far, the compositions of Irn-Bru, Ribena and Lucozade having all been adjusted before its introduction earlier this month, the better that they would fall under its threshold (18p a litre for drinks containing between 5g and 8g of sugar per 100ml, and 24p for those with 8g or more). For another, there’s the question of fairness: why, they ask, should only some companies be forced to take action (or pay the price), when others are getting away scot-free?

These things apart, I’m on their side for another reason – one that has to do, I suppose, with an awareness of my own failings (see above) when it comes to sugar. What I mean is that I have the sense more and more that we’re all in this together; that the obesity crisis is an octopus whose tentacles reach into every place where food is bought or consumed, whether smart or dreary, and into every family, whether rich or poor. In a less dysfunctional world, the tax on sugar would rise a little every few years just as it does on tobacco. In an ideal one, its threshold would be reduced until it is close to zero. What interests me about such ideas, though, is not how radical they sound, but how ultimately feeble. Even if we are one day able to limit the damage caused by sugar, we all of us know its power will endure. It recruits us early, safe in the knowledge that its appeal is both instant and abiding – an allure no form of taxation is likely ever to diminish. Even as I read over this piece, checking my facts and wallowing just a bit in my guilt and indignation, I find that my mind is inevitably turning to what I may find downstairs, stowed carefully behind some ancient box of lentils, that bag of bulgar wheat I can never quite be bothered to use.