I liked this article I read today in the The Guardian. It brings to mind all the garbage you see online and being published by the new life-style gurus (no names mentioned) who encourage you to go buy all sorts of expensive foods in order to make their exotic recipes, whereas a visit to the farmers’ market will give you a good mix of everything you need – bar the pulses, which you can get at almost any corner shop or your local supermarket.

I know my recipes are very Asian-based, but that’s because that was what I could get in Singapore – now I am back in London, I shall be turning my attention to more local, seasonal dishes, but with a twist. After all garlic, ginger and chilli aren’t going to break the bank! Nevertheless I still avoid eating pizzas, pasta and any refined carbs and sugars, although sometimes a little sinning does you good!

A healthy diet is not about Instagrammed asparagus, glowing skin or a feeling of wellbeing – it’s about eating foods that help you to avoid disease. That simple message has been muddied by pseudoscience nutritionists and celebrity health gurus, clambering over each other to persuade you to buy their products.

With a healthy diet you can avoid risk factors such as being overweight, having high blood pressure and developing diabetes, which lead to serious cardiovascular diseases such as heart attacks and strokes. It’s concerning, then, with the burden of obesity and disease falling on the poor, that health is being packaged and sold through a soft-focus lens as an aspirational product beyond many people’s means.

Nothing could be further from the truth. The much-vaunted Mediterranean diet, for instance, is one of peasants. Born of a needs-must school of eating, it emphasises varied, seasonal, humble and largely plant-based ingredients: fruit and veg, fibrous carbs, legumes, nuts, a bit of meat, and healthy fats such as olive oil. Doesn’t sound too expensive, does it?

Most nutritionists and health gurus agree with doctors and scientists on the fundamentals of a healthy diet – the idea is to eat more protective foods and fewer damaging ones. Anything else is a selling point people use to stand out in the marketplace.

Here we look at the basic pillars of a healthy diet with ingredients and recipes that follow three guiding principles: they are accessible, inexpensive and simple to cook.

Fruit and veg

Fruit and veg are good for you, but even this message has been spun to make money.

They’re not good for you because of magical detoxifying properties. Whether it’s goji or acai berries or concentrated vegetable gloop, these things often come with scientific-sounding words, such as flavonoids and antioxidants, attached, usually just to sell you something.

Catherine Collins, dietitian at St George’s hospital, London, says that pseudoscientists latch onto the fact that there are chemicals in all fruit and veg which affect our health. “But they cherrypick scientific concepts and make simplistic, unproven associations with human health and specific outcomes to justify their viewpoint,” she says.

What we do know is that by eating fruit and veg you can lower the risk of disease. Because they contain artery-relaxing nitrates, familiar vegetables such as spinach, lettuce and radishes, can lower blood pressure. The potassium in green leafy veg, squash and mushrooms does the same. These vegetables might not be glamorous, but given that high blood pressure has overtaken smoking as the leading risk for disease and death you’d be foolish to push them to the side of your plate.

Fats

That saturated fats aren’t as bad as once thought has led to PR spin that has only confused matters. A prime example is coconut oil. With no good evidence that eating coconut oil regularly will keep you healthy, inaccurate marketing has used interesting theoretical health properties to make it more desirable.

Saturated fats such as butter, if enjoyed sensibly, are neutral to your health: they are not protective like olive oil but are not damaging like trans fats or excess sugars. It’s unsaturated ones from whole food sources such as oily fish, nuts, seeds and olive oil that should be your fats of choice.

Where evidence is strongest is with boring olive oil. There’s no need to fork out for the expensive stuff, the economical extra-virgin type will do fine. Watch out for processed spreads and fats branded as omega-3 fortified and mayonnaise with 5% added olive oil. If you’re eating it in a bid to be extra healthy, you’re wasting your time.

Oily fish can be a little trickier – its shelf life can make it difficult to squeeze into a busy family’s schedule Its expense, too, can be prohibitive. Unless you’re Richard Branson or a grizzly bear with a fishing rod, you’re unlikely to be able to eat as much salmon as you’d like, but there are options that aren’t so hard on the wallet.

Grilled mackerel in the summer is always a winner. Cornish sardines are increasingly popular since their rebranding (they were once the more drab-sounding pilchards). Canned fish such as traditional sardines can be store-cupboard superstars but tuna, although classified as oily when fresh, loses much of its omega-3 when canned.

Avocados, nuts and seeds are another good supplementary source to top up your intake. Know where to buy them and they don’t have to be expensive. Ignore them altogether and they can cost you a healthy heart.

Carbs

It seems we have a limited capacity for understanding what bad foods are. As fats have benefited from a PR makeover, carbs have been put in the stocks. Restricting your carb intake is an effective way to lose weight, but to vilify a whole food group by banishing them forever would be to make the same mistakes all over again.

Good carbohydrate sources are unrefined, fibre-rich ones such as oats, wholegrains, quinoa, sweet potatoes, squash and legumes, all of which release their sugars slowly. Bad carbs are refined ones such as the white flour used to make white bread and pasta: the refining process takes out all the fibre and leaves you with easily digestible sugar.

There’s only one problem: refined carbohydrates are delicious. We’ve evolved to crave energy-dense foods so don’t deny yourself – just manage how much refined carbohydrate you eat. You can do this by eating a cauliflower crust pizza but, if you’re anything like us, you’ll end up wanting to throw that pizza in the bin after a few bites. If you want pizza eat a proper one, just don’t make it a habit.

Brown pasta, too, is about as fun as eating cardboard. Italians don’t eat it so why should you? You can have regular pasta, but limit it to about a quarter of your plate and balance it with other fibre-rich elements such as vegetables that will slow down your digestion and limit the spikes in sugar your liver turns into harmful fats.

An obvious way to avoid sugar spikes is to avoid sugar. But there’s no point splashing out on apparently healthy alternatives such as agave nectar, honey or date molasses. These alternatives, says Nita Forouhi, a diabetes clinician-scientist at the MRC Epidemiology Unit, University of Cambridge, are marketed as “having antioxidants or a lower GI [glycemic index] value, but there’s no convincing evidence to support swapping table sugar for any of them for health benefits – they are all ‘free sugars’ which as a rule we should limit”.

Protein

The apparent health benefits of protein have been thrust into our faces one Instagrammed workout at a time. This link between protein and health, though, is the embodiment of the misunderstanding of what health is: it’s not about six packs and bubble butts, it’s about the avoidance of disease and premature death, admittedly unsexy but undeniably important factors that eating more protein will not improve.

That’s not to say proteins aren’t important. They’re the building blocks of what makes you (muscles and bones), what holds you together (skin and cartilage) and what keeps everything ticking along (enzymes and hormones).

Eating meat is an easy way to get your protein – the animal does all the hard work and concentrates the nutrients for you – but it can be expensive, you can’t eat it if you’re a vegetarian, and if you eat too much of it you won’t have space left for more protective foods.

Although meat is not essential for health, for many it’s a key part of any meal. The good news is that we can get those satisfying umami flavours we crave as often as we want without breaking the bank or eating too much. As with many peasant dishes of the Mediterranean diet, cooking techniques such as stewing and braising stretch the flavour to other ingredients, such as fibre-rich vegetables. You can also use cheaper cuts such as shin and skirt steak: just go for quality over quantity.

Vegetarians, fear not: fibre-rich beans and pulses (legumes), while being a great source of protein, are associated with long-term health protection and so should also be a go-to food for meat eaters. Nuts and seeds, too, can bulk out a salad and their protective fats will leave you fuller for longer.

Other than low-quality processed meats there are no bad proteins. Try to trade up excess meat for more protective foods whenever you can – a healthy diet will protect you from disease more than a six-pack ever will.