I ADMIT to a guilty chortle this week at a tweet comparing Nicola Sturgeon to a "raging maw" clamping down on her wayward weans following the independence referendum.

"Vote no?", was the jist of it. "Then no sweeties, alcohol or cigarettes for you. Now we're all miserable. You happy?"

Ms Sturgeon will be familiar with nanny state claims against her, having come through the battle for minimum pricing and plain cigarette packaging. It was a guilty chortle because, firstly, it's nonsense, and secondly it's sexist.

I thought about this tweet as I read of the head master of fee-paying Brighton College banning disposable plastic bottles with the threat that those who continue to use them will face the same punitive outcome as those caught smoking on campus. One sanction, the headie said, would be supervised beach cleaning.

Sometimes you need a mammy or a nanny or a demon headmaster to step in, take away your Evian bottle/Silk Cut/espresso martini and stick you on the naughty step. But just as toddlers rebel, so too do adults.

Ms Sturgeon this week announced a Scottish Government pledge to cut childhood obesity by half by 2030. A healthy weight and diet plan is due to be published in the summer and Ms Sturgeon was photographed with the celebrity chef and childhood obesity campaigner Jamie Oliver talking it over.

Part of the plan is a radical crackdown on junk food, which generated headlines about the end of two-for-one pizza deals while unimpressed commentators on social media pointed out the two-for-one pizza deals at the Jamie's Italian chain of restaurants.

It's always the takeaway outlets and junk food purveyors that are targeted by the well meaning. I sat this week in a hipster cafe and mulled this over while eating a French toast ice cream sandwich, which was delicious but sheer greed on top of a cheese fondue sourdough concoction glimmering with little puddles of oil.

It's never hipster cafes at the heart of obesity strategies.

Glasgow City Council has been piloting a scheme in the east end of the city encouraging fast food outlets around schools to tweak their menu so that dishes contain less fat, salt and sugar. No one's going after the halloumi and cacao pancake brigade, are they?

That's the problem with a health crackdown: more often than not, it targets those at the lower end of the socio-economic scale. There is no doubt obesity is a huge problem in Scotland, it is having a crippling impact on the NHS and there can be no dissent that something must be done. But what?

Healthy eating takes money, for the food itself and the utility costs to cook it, and time, for shopping and for cooking. Can the government provide families with extra money and free time?

Childhood obesity is driven by poverty. It is not that struggling families don't want to feed their children healthy food or don't care to. It is that high energy, cheap food that, importantly, won't be rejected by children, is often unhealthy. Instead of scrapping two-for-one deals, the deals should be shifted to healthier items.

Subsidies could be given to low income families for supermarket shops - it is, after all, a public health crisis.

We're repeatedly told that eating well means cooking from scratch but this takes time. I've seen this disputed - usually by professional cooks - but I've made concerted efforts to cook everything from scratch for a week or two and it requires a hellish amount of discipline. "Just stick it all in a slow cooker" is a common refrain. Nice if you have the upfront cost of a slow cooker to spare and a kitchen big enough to hold one.

Food is a deeply personal and as well as deeply practical issue. Our emotional links with food mean mental health and wellbeing must be part of any obesity strategy. Physical activity must also be prioritised.

In Glasgow this week the SNP administration has scrapped free swimming for children and pensioners. Health must be prioritised at a government and local level for any strategy to impact.

Compulsion is balked at but this is what we've signed up to: free public healthcare as a collective.

Yet it is clear in the frustration expressed towards Ms Sturgeon and the disdain with which Jamie Oliver is regularly greeted that the populace will have to be persuaded.

For those of us who can afford to eat as we like, personal choice comes with personal responsibility to the system we benefit from. That means less sneering about nanny states and more willingness to back solutions to the problem, solutions to which are vital but not something that will be easily or quickly whipped up.