What do refined sugars and freedom of speech have in common? The answer is: Nothing much, other than I’m going to talk about them both in this column.

Allow me to explain: About a month ago, I gave up refined sugar. Now, I must add a caveat, here. When I say ‘gave up’ I mean ‘avoided to the best of my knowledge’. I stopped eating chocolate and began refusing cakes and biscuits proffered in staff rooms (which took a momentous effort of will). I have never taken sugar in my tea or coffee so that was sorted and I don’t drink fruit juices but, if I did, I would have begun eschewing those. In short, what I was actually giving up were added sugars. I still ate fruit and things (the homes of natural sugars) - I didn’t do the full Gillian McKeath.

Anyway, the effect on my mood was both immediate and momentous. I no longer suffered what I referred to as ‘the 3pm slump’. I had a consistent, manageable amount of energy throughout the day. And (this may be TMI, apologies if it is) my legendary PMS (in which I cry at TV adverts and not because they’re manipulating us all towards terrifyingly prescriptive notions of success and happiness but because I’m genuinely moved) was all but non-existent.

Being, as I am, a person of extremes, I decided after the success of the sugar experiment that I’d also try to give up carbs. Because they are also sort of sugar, if you think about it. Exactly one week later I looked in the mirror and got the shock of my life. I had huge great big purple circles under each eye. Not only that but I felt what my Nan might refer to as ‘bone tired’. I was schlepping around like Harry Enfield’s Kevin the Teenager, grunting vaguely when asked a question, unable to summon enthusiasm for anything.

I sent a text to a doctor friend of mine: “Of course you shouldn’t cut out starch, you great galumphing tit” came the response (I am assured she doesn’t talk to her patients in this way). “Carbs are your body’s main energy source. Without them you’re running on empty. They’re really good for you. What on Earth made you think you should give them up?”

I thought about it and then I realised, with some shame, that the idea had been subconsciously planted in the recesses of my brain by ‘selebriddy’ magazines. ‘Celebs’ are always ‘cutting out carbs’, or so the mags would have us believe, and the result is a toned, tanned, bright eyed, youthful, healthy wondrousness.

Now, I consider myself to be a reasonably intelligent person with sufficient critical faculty to question prevailing media narratives. Yet still, it seems, I had unwittingly taken on board an ideal that wasn’t at all healthy from a source that wasn’t at all well-meaning, without even realising it. I’m okay with this - I’m self-aware enough to know that, just like everyone else, I’m somewhat brainwashed by my environment - the important thing is that I had a subsequent realisation.

Fast forward to Tuesday of last week, where I found myself in the car park of Magna Carter School in Surrey, conducting a remote Sky News ‘debate’ with an entirely mirthless individual who claimed to be from something like the ‘Free Speech Society’ (it’s difficult to concentrate when you’re shivering in 30mph gales and distracted by cars crunching over gravel every 30 seconds). We were discussing a news story in which it was discovered that introducing western TV to remote, rural tribes caused them to favour thinner female beauty ideals.

My opponent considered the experiment to be ‘patronising’, whereas I thought it was immoral but not at all surprising. She claimed it was insulting to suggest that anyone is affected by the narrow beauty paradigms fed to us by the media, as we are all free thinking individuals with brains that can chose for ourselves… Which is a lovely notion, unfortunately belied by the existence of multi-billion pound beauty, fashion and plastic surgery industries designed to ‘help’ us subscribe to the self-same narrow beauty paradigms fed to us by the media.

A huge part of my body image class for teenagers is about questioning - social media, pornography, magazines and television have the ability to be either a) diverting light entertainment with not much moral consequence or b) a symbol of all the most evil aspects of modern living, depending on how we receive them. If we are able to view them with a critical mind, aware of the agendas, any negative impact will be minimised, yet still some toxic hokum might slip through the net (as my carb story attests).

The worst thing we can do is insist that we aren’t brainwashed and bury our heads in the sand. We are born into a world where girls wear pink baby grows with ‘Princess’ written on them and then watch cartoons where they learn that ‘princess’ means having a 16 inch waist and waiting for life to start when you’re rescued by a man. Boys, conversely wear blue baby grows with ‘hero’ written on them and watch cartoons where they learn that ‘hero’ means having chests the size of a bungalow and never talking about their feelings. And so they are introduced to a world in which advertising, media and pornography have become the wallpaper, speaking to us in our most relaxed (and therefore suggestable) moments with images that convey a thousand self-esteem bashing words. We are born on the back foot, as far as our ability to like ourselves is concerned.

Is it any wonder, then, that according to a study by Girl Guiding in 2012, by the time they are 12, 48 per cent of teenage girls avoid every-day school activities because of body image insecurity? And these girls aren’t, despite what my Sky News debating partner might suggest, stupid. In fact, there’s a lot of evidence to link the taking-on of media-fed beauty ideals with empathy.

Teaching children from an early age to question everything is the only way I have found to combat this (I tried to take on capitalism once, but it was a venture doomed to failure). To do so isn’t an assault on ‘freedom of speech’ or to imply that human beings aren’t capable of thinking for themselves. It’s simply to prepare young people for an environment where some of our most creative brains have spent multi-millions of pound trying to make them insecure (and therefore more likely to consume), during a time when they are still trying to discover who they are.

Natasha Devon is the Department for Education’s mental health champion. She tweets at @natashadevonMBE

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