If you’ve been alive for the last few years, you’ve almost certainly heard the message. It has been whispered in talk shows, printed in glossy magazines and hardcovers across the country, yelled out by opinion leaders all around the globe.

You see, the experts are wrong. Instead of eating according to the dietary guidelines, we should be going paleo (but not actually eating like paleolithic man, who, among other things, was a cheerful cannibal. It’s more like a modern approximation of what paleolithic man might have eaten if he’d happened to be at a New York deli or a gourmet salad bar and had to choose between quinoa and couscous and could get past the sudden terror of being dragged from his safe cave long enough to actually make a decision), trying keto, or eating fermented cabbage that’s been steeped in a heady concoction of vinegar and privilege because, really, that’s the way you stay healthy.

This is, of course, nonsense.

Dietary guidelines – at least in Australia – are complicated, lengthy prescriptions about eating as well as overall health. They can be hard to understand, difficult to implement, and in certain cases are not very helpful.

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But they are based on very solid reviews of strong scientific evidence. They may not always be right, but they definitely aren’t wrong.

What are dietary guidelines?

The main dietary guideline document can be found here, and if you’ve got an entire day to kill it’s definitely something I’d recommend reading. The guidelines are essentially a public health tool developed by the government to a) help clinicians – doctors and dietitians mostly – to give dietary advice to their patients and b) provide a platform for the average person like you or I to build a healthy diet from.

If that sounds simple to you, just wait. Diet is never simple.

The most important thing to remember here is that the dietary guidelines are not a single prescription for a healthy diet. There are, obviously, ways to eat healthily without conforming to every recommendation in the guidelines. For example, the recommendation to eat a lot of carbs is ignored by some people on what’s know as ketogenic diets, and they are rarely in danger because of it. But that’s not the point: the guidelines are there to provide a diet for every person in Australia, from rural and remote communities to city dwellers like myself.

And that means talking about foods that are available everywhere.

What this means is that the dietary guidelines tread a fine line of being incredibly complex and overly simplistic – they have to speak to the average person on the street and yet still provide meaningful ways in which to change your diet to be healthier. It is not easy.

The science

For all of the criticisms of dietary guidelines, there’s little engagement with the actual science that sits behind them.

For the current swathe of dietary recommendations, the National Health and Medical Research Council commissioned an enormous review into the scientific evidence behind diet in Australia, which was published alongside the guidelines in 2013. It’s a little out-of-date now – the guidelines are updated every five years, so we’re due for an update soon – but still represents a mammoth effort to look at every health claim made about food and come up with useful recommendations about what we should eat. And it really does include a staggering amount of evidence: most of the guidelines are based on several systematic reviews, which are themselves based on dozens of studies.

Overall, the guidelines are based on literally hundreds of individual pieces of scientific research, representing the perspectives of millions of people.

Saying that they’re “wrong” is a bit like arguing that vaccinations are a waste of time – you can have an issue with an individual recommendation, or even some specific studies that went into them, but the guidelines represent a huge chunk of evidence. Calling them “wrong” is either a vast oversimplification or a display of unrepentant ignorance about what they actually are. Most people who do it have simply cherry-picked their favourite study and completely ignore the research that disagrees with them.

There’s very little scientific disagreement that, if you eat according to the guidelines, you’ll be healthy.

But is that the end of the story?

Socioeconomic woes

Aside from self-educated celebrity chefs, the biggest criticism about dietary guidelines is that they don’t fulfil their purpose. “We’ve had guidelines for decades now,” the argument goes “Why are we still getting less healthy?”.

This is a more difficult question to answer.

The first thing to do is actually read the guidelines. If you have a look, right up there in the first section and at the start of every part thereafter is a large paragraph. It talks about something called “socioeconomic factors” which basically means “stuff that makes it harder to be healthy that is outside individual control”. This includes things like urban design, level of education, having parents in prison, and most importantly access to fresh fruit and vegetables. What the guidelines say, front and centre, is that telling people to eat right is useless if we don’t also make it easier for them to do so.

And this, sadly, is something that we still haven’t done.

If we truly want to fix our issues with eating – in particular obesity – it’s not enough to just put out recommendations about foods that are healthier. We have to change our environment to make it easier for everyone to eat healthy foods and harder to access less healthy things such as sugar-sweetened drinks and chocolate.

Which is, of course, what the guidelines recommend.

Dietary guidelines aren’t a panacea for our health problems. They aren’t going to fix society overnight. But they are good advice that the vast majority of people can understand providing a framework for a healthy diet.

It’s up to us, as a society, to make it possible for them to do so.

• Gideon Meyerowitz-Katz is an epidemiologist working in chronic disease