Multi-millionaire, celebrity activists are never likely to win many popularity contests among the public and media commentators. The TV chef, Jamie Oliver, compounds this tendency by cultivating a motor-mouthed, Essex-boy schtick that seems almost calculated to grind on people’s nerves. A decent chunk of the population will never, ever be able to stand this foodie crusader, with his pukka-patter and high-profile campaigns, usually accompanied by successful TV programmes that drive his fame to yet greater heights.

Jamie is the culinary world’s answer to Bono and, for the gate-keepers of our popular culture, he’s just as uncool as the preachy Irish singer.

Yet, I must confess, I don’t care.

Just as U2’s chiming, exultant rock anthems made life better (at least in the 80s and 90s, when they were still good), so too have Oliver’s unpretentious, easy to follow recipes.

His television programmes helped popularise the blend of cooking and feel-good lifestyle footage that now dominates the schedules, but we can hardly blame him for adopting a successful formula ahead of countless pallid copyists. And, if he’s worried about the obesity epidemic and believes he can use his position to get the nation eating better, then good for him.

It’s easy to sneer at someone with a bulging bank account seemingly advising poorer people how they should best spend their money. Then again, most of Oliver’s campaigns have been aimed at making it easier to make better choices, rather than closing down unhealthy options altogether.

The whole point of Jamie’s School Dinners, the chef’s s most prominent campaigning series, was that healthy, nutritious food was frequently entirely absent from school lunch menus. Fizzy drinks are often considered a source of hidden calories about which many consumers are ignorant and they’re consumed, disproportionately, by children and teenagers. There has undeniably been an explosion of junk food advertising, not only on TV, but on digital and social media too.

Oliver doesn’t peddle ridiculous aspirational diets or the latest trendy food fads. You’re more likely to find him demonstrating how to make a decent spag bol or a hearty sausage bake, rather than dousing kale in turmeric or recommending a bracing coffee enema. Unlike his chum, Hugh Fearnley- Whittingstall, he doesn’t suggest  that veganism has to be the direction of travel for our eating habits (while lacking the firmness of purpose to become a vegan himself).

The libertarian view is that people have an absolute right to eat themselves into bariatric mobility scooters, diabetic comas and, ultimately, early graves, because they own their bodies outright and can do with them as they wish. In principle, that’s a difficult argument to refute, but it’s not to say that campaigners like Oliver shouldn’t try to discourage behaviour that harms individuals and exacts heavy financial costs on our society.

The broadcaster has been guilty of making an occasional patronising remark about the links between poverty and obesity. But I’ve yet to hear him say anything quite as condescending as Alex Massie, his latest media critic, who this weekend argued that impoverished people need the “measure of relief” offered by a “Big Mac and a can of cheap lager” to offset their lives of drudgery.

The fact that, as a nation, we’re getting fatter, thanks to a combination of bad diet and lack of exercise, is no longer up for serious debate. Cancer Research UK recently estimated that 70% of Britons born between the early 1980s and the mid-1990s will become dangerously overweight before they reach middle age. Obesity may already have overtaken smoking as the UK’s biggest killer. (Editor’s note: Massie is a smoker.)

Only the most purist libertarians now regret the health battle that government and society waged successfully against smoking.

Not, of course, that the same tactics can all be applied directly to fatty or sugary foods. Even the odd cigarette does some level of harm, whereas everyone needs food, and passive eating is unlikely to become a pressing issue, unless the latest diet trend involves shoving the remains of your chocolate eclair into a stranger’s gob.

Still, a powerful industry is devoted to advertising and selling as much poor quality food as it possibly can to people who are becoming steadily fatter and sicker as a result. In this fight, the chefs and medical professionals campaigning for a healthier nation are hardly the bad guys. Our personal freedoms will not collapse because Jamie Oliver wants us to eat less rubbish.

In fact, to conclude with something like a personal testimony, Jamie really can make a difference. There may have been other civilising factors, like growing older, getting married and starting a family, but before I was exposed to Oliver’s beginners’ cookbook, Ministry of Food, more often than not I dined on tinned curry of an evening. For a very special treat, I sometimes heated it up and served it on a plate.