Heart diseases are among the globe's biggest health challenges. Thankfully, the nutrients hidden away in some of our favourite foods can have huge (and lasting) impacts on our hearts' overall wellbeing. Here, we reveal the ingredients that can help to prevent cardiovascular diseases and keep your heart happy – with tips on how to maximise their benefits, courtesy of a registered nutritionist.

Click or scroll through our gallery to discover our A-Z of the best foods to eat to boost heart health, from anchovies to wholegrain bread.

"There is no better food for the heart than fish," says registered nutritionist Lucy Williamson. "The omega-3s in fish are a vital nutrient, yet so many people don't like to cook with it." To benefit your heart, try adding anchovies to your diet – not the salty filleted variety, but the whole fish, which you can buy either fresh or frozen. Anchovies are a great source of omega-3s, and they're delicious served Mediterranean style: with a squeeze of lemon.

Ever tried adding barley flakes to your muesli, overnight oats or smoothies? Here's why you should. "Increased fibre in our diet really helps to keep blood sugar steady," says Lucy. "When we absorb sugar from our food, it's actually a toxin in our blood – it can irritate the linings of the blood vessels – so we need to get it quickly out of our blood and into our tissues, where we can use it." Barley flakes will up your fibre intake, reducing the absorption rate of sugar, and thereby keeping blood sugar low.

Beetroot juice contains an active plant chemical, nitric oxide, which is proven to help promote blood flow and reduce blood pressure. The deep, earthy flavour of beetroot can make it unpopular, so try pairing it with sharp flavours: apples and citrus fruits make great additions to fresh beet juice. Prefer to eat your beetroot, rather than drink it? Try it with creamy, slightly sour goats' cheese.

Heard that blueberries are good for boosting heart health? It's all thanks to the antioxidants they contain. "Sugar damages the lining of our blood vessels, almost making them go furry on the inside," says Lucy. "That cell damage on the inside of our blood vessels is being repaired all the time by antioxidants. That's why we say they're anti-ageing: they're constantly repairing damage." Research shows that fresh, frozen and dried blueberries are all good sources of these amazing nutrients.

Delicious, indulgent and packed with cholesterol-stabilising monounsaturated fats, these creamy nuts make a saintly snack. But if a handful of Brazil nuts doesn't do it for you, try working them into some of your favourite recipes. Ground to a fine sandy powder, Brazil nuts would be perfect in a rich pesto – and they'd also add a gorgeous nuttiness to shortbread or chocolate brownies. Just remember that all fatty nuts and seeds should be eaten fairly fresh; their crunch and clean flavours can quickly turn stale.

If you're already eating tabbouleh on a regular basis, you get a gold star. If not, it's time to start. Bulgur wheat, cracked wholegrain wheat berries commonly eaten in the Middle East and Mediterranean, has the highest fibre content of any wholegrain. "Robust research shows that if you have more fibre, it's a really good way to reduce the LDL cholesterol – the bad kind – in your blood," says Lucy. "Straight away that impacts heart health, because your arteries and cardiovascular system are healthier." Balancing cholesterol, a waxy fat in our blood, is a key benefit of fibre, and most of us don't get enough of it in our diets.

Hold onto your hats – everything we've been told about saturated fats may need revising. US research published in the journal Nature suggests that saturated fats from dairy are very different from those in meat. "We're beginning to recognise they can reduce the risk of heart disease and protect against diabetes, completely flipping the received wisdom," says Lucy. While anyone with raised cholesterol should choose low-fat dairy and plant oils, adding a knob of butter to your steamed vegetables is a good way to get your fix of heart-healthy pantadecylic acid.

A punnet of ripe cherries is an uplifting treat for the soul – but did you know that it's just as good for your heart? Cherries' deep-red skins and ruby flesh are a clue: like blueberries, they contain high-pigment antioxidants that help repair cell damage. American research suggests that eating a portion of berries a day helps to keep arteries healthy. The frozen fruits retain their nutrients well, but if you want to use canned, remember that about half the antioxidants will have seeped into the syrup.

Perfect in hearty porridge or baked into protein bars, these Central American seeds are packed with healthy nutrients, including a huge dose of omega-3 essential fatty acids. It's one of the reasons chia seeds have become such a valued ingredient in recent years. However, if you're following a plant-based diet, take note: "It's important to remember that the omega-3s from any plant source need to be converted by our bodies into a heart-healthy form," says Lucy. "That's quite an inefficient process, so I recommend that anyone relying on plant sources should use an omega-3 supplement, too."

Here's the one we've all been holding out for – but tread carefully! The heart-healthy ingredients in dark chocolate are the antioxidants that come from the cacao fruit; these nutrients work hard to repair the damage sugar does to our cells. "So make sure to check labels and find a bar with at least 70% cocoa solids and very little sugar or additives," advises Lucy. "That way, you get the benefits to your blood vessels and also to your gut health."

Another handy plant source of heart-healthy omega-3s and fibre, flaxseeds are proven to reduce the dangerous fatty buildup in arteries by as much as 70%, if taken daily. So how do you add them to your diet? Beyond sprinkling them over cereals and into smoothies (which will give you great digestive benefits), you could try blitzing flaxseeds up with nuts, seeds or flour to add to a biscuit dough or cake batter. Breaking the tough shell will release more of the nutrients your heart needs.

Research shows this wonder bulb lowers blood pressure – which is a huge win, as dangerously high pressure within artery walls affects one in four adults worldwide. "Garlic is also shown by new research to be really helpful in supporting our appetite mechanisms," says Lucy. "Obesity is a real issue for heart health, so helping us stop overeating is really great for our hearts." Try thoum – a Lebanese garlic sauce – for a real hit. To make it, blitz freshly peeled cloves, then slowly blend in a thin stream of oil and lemon juice.

Pickled herring salads might traditionally be the preserve of Scandinavia and Eastern Europe, but people across the world can benefit from eating more of this oily fish. Herrings are super-high in omega-3s, with nearly double the content of mackerel. They're also a relatively cheap option that's easy to find fresh, smoked or canned. Pickle-cured fillets might suit anyone struggling with the fish's strong flavour; vinegar and spice – not to mention a traditional onion garnish – are the perfect disguise.

Research shows that eating mackerel at least once a week can reduce the risk of a heart attack, especially in post-menopausal women.  It's well worth working into your diet, even if you struggle with the thought of cooking fish. "Smoked mackerel is really easy because it's already cooked. It's a really quick win," says Lucy. Try it on jacket potatoes, flaked into salads or chunked into salsa-packed tacos.

You'll probably know oats are a go-to for helping heart health, but have you considered oatmeal – the chopped oat kernel, rather than the more familiar flakes? Using this fine meal to enrich crumb coatings, make biscuits, pad out stuffings or change up your crumble toppings can be really worthwhile. "If we increase the amount of oatmeal in our diet, it's really good for our blood cholesterol," says Lucy. "It contains a specific type of fibre that's been shown to be particularly effective."

This fragrant and flavoursome oil has long been proven to support heart health – as you'd expect of an ingredient that's central to the celebrated Mediterranean diet. British research shows that the combination of unsaturated fats and nitrite-rich olives reduces blood pressure. Getting more of your calories from this omega-rich plant oil, and less from the nutrient-stripped fats in ultra-processed foods, is a real win for your heart.

Though it's true that US research has found that those eating red meat have a marginally higher risk of heart problems than vegetarians, putting your meat budget towards higher-quality beef could pay off. "100% grass-fed beef can have up to 300 times the omega-3 content of conventionally farmed beef," says Lucy. "With organic beef, you know the animals are out in pasture for the majority of the year, so they're getting all those good oils from the grass they're eating – that's really heart healthy, and better for the planet, too."

Processed plant proteins might not be a particular favourite of health-food fans – but since we've been talking about the cons of conventionally farmed meat, it's worth highlighting a recent Canadian review of research. Its lead author found that plant alternatives consistently served lower risks to cardiovascular health than meat. This suggests that if you're choosing between a basic, industrially made beef burger and a commercial plant alternative, the vegan option should be better for your heart.

Sprinkled over the likes of tagines, pilafs and salads, the zingy, sweet-and-sharp seeds of a pomegranate are key to many a Middle Eastern dish. Each jewel-like seed is packed with antioxidants, and drinking their juice – a regular habit in many cultures – is proven to reduce blood pressure. Interestingly, American research suggests that adding three dates to half a glass of homemade pomegranate juice (including the crunchy pits) will boost its heart disease–fighting qualities.

Cold-pressed rapeseed oil (the bright yellow liquid that comes in slender glass bottles, rather than the bulk vegetable oil that's been stripped of its nutrients) is another ally in your quest for good heart health. "It's actually higher in omega-3s than olive oil, and it's really good for cooking at high temperatures," says Lucy. So, whereas olive oil is best used as a cold dressing, rapeseed oil is ideal for using to soften onions, warm garlic, sauté mushrooms, or fry eggs.

With roughly the same omega-3 content as herring, versatile salmon can star in countless dishes – from poke bowls and platters of nigiri to hearty chowders and pastry-wrapped Wellingtons. "Most people really enjoy salmon, which is great because oily fish is really the best food for your heart," says Lucy. She recommends fresh salmon over smoked; the high salt content and expense of the cured fish make eating the advised 5oz (140g) recommended portion size a tough feat.

Canned sardines are an excellent addition to any pantry, offering an instant portion of tasty protein that's also high in omega-3s, vitamins and minerals. Make the most of a tin by mashing it into cooled potatoes to form fishcakes, or try stirring it through spaghetti with some raisins and pine nuts to create pasta con le sarde (a Sicilian delicacy). Alternatively, just spread it on crostini for a small and nutritious bite. Enjoying sardines once or twice a week could reduce your risk of heart disease by more than a third.

Did you know that a small handful of walnuts (the recommended daily portion) contains almost twice the amount of antioxidants of other popular nuts? That's the analysis presented to the American Chemical Society, building on years of research into the nuts' heart-healthy properties. The best way to eat walnuts is raw and unsalted, so try blitzing yours into a chunky crumb to stir through pasta, blend into pesto, sprinkle over salads or add to yogurt bowls.

Bread, in all its many forms, tends to be high in carbohydrates, which are linked with obesity – which, in turn, is linked with heart disease. "Nutritionists talk about 'metabolic health'; that includes your weight and the fluctuation of sugar in your blood stream," says Lucy. "Your metabolic health really impacts your risk of heart disease." Swap white, ultra-processed loaves for higher-fibre wholemeal choices (and breads free from added sugars) to reduce the unhelpful effect bread can have on the health of your heart.

Now discover our A-Z of foods that can help improve your gut health