Heart-Healthy Eating: The Foods Cardiologists Actually Recommend

No dietary pattern has more robust evidence for cardiovascular protection than the Mediterranean diet. The landmark PREDIMED trial randomised over 7,000 high-cardiovascular-risk adults to one of three diets: Mediterranean diet supplemented with extra-virgin olive oil, Mediterranean diet supplemented with mixed nuts, or a low-fat control diet. The Mediterranean diet groups showed a 30% relative reduction in major cardiovascular events compared to the low-fat group — a magnitude of benefit comparable to many pharmaceutical interventions.

The Mediterranean diet is characterised by high consumption of olive oil, vegetables, legumes, whole grains, nuts, seeds, fruit and fish; moderate consumption of poultry and dairy; and low consumption of red meat, processed meat and added sugars. Its cardiovascular benefits operate through multiple pathways: anti-inflammatory effects of olive oil polyphenols, omega-3 fatty acids from fish improving lipid profiles and reducing arrhythmia risk, soluble fibre from legumes and oats lowering LDL cholesterol, and the overall dietary pattern producing more favourable effects on blood pressure, blood sugar and endothelial function than isolated nutrients could achieve alone. Adopting even the core elements of the Mediterranean pattern — more olive oil, more fish, more legumes, more vegetables — produces measurable cardiovascular benefit.

The dietary fat story has been revised substantially over the past two decades. The original low-fat dietary advice that dominated cardiology from the 1960s to 2000s — based on the hypothesis that all dietary fat raises LDL cholesterol and therefore causes heart disease — has been substantially nuanced. The reality is that fat quality matters far more than fat quantity.

Saturated fat (found in red meat, butter, full-fat dairy, coconut oil, processed foods) raises both LDL (bad) and HDL (good) cholesterol. When it replaces refined carbohydrates in the diet, the effect on cardiovascular risk is roughly neutral. When saturated fat is replaced by unsaturated fat, cardiovascular risk falls. Trans fats (partially hydrogenated vegetable oils, found in some margarines, commercial pastries and fried foods) unambiguously increase cardiovascular risk by raising LDL and lowering HDL simultaneously — these should be minimised to zero. Monounsaturated fat (olive oil, avocados, most nuts) consistently improves lipid profiles and reduces cardiovascular risk. Polyunsaturated fat — particularly omega-6 (sunflower oil, nuts, seeds) and omega-3 (oily fish, flaxseed, walnuts) — reduces LDL, reduces inflammation and lowers cardiovascular risk. The most cardiovascular-protective dietary fat change most people can make is replacing saturated and trans fats with unsaturated fats from olive oil, nuts, seeds, avocado and oily fish.

Omega-3 fatty acids, particularly the long-chain marine forms EPA and DHA found in oily fish, are among the most studied nutrients in cardiovascular medicine. Their proposed mechanisms of cardiovascular benefit include reducing triglycerides (by 20–30% at therapeutic doses), reducing platelet aggregation, decreasing inflammatory markers, modestly lowering blood pressure, reducing cardiac arrhythmia susceptibility, and improving endothelial function.

The evidence for eating oily fish 2–3 times per week and cardiovascular outcomes is strong from observational studies, and supported by mechanistic evidence. The evidence for omega-3 supplements is more mixed: at high doses (4 g/day of prescription-grade EPA or EPA-DHA combinations), randomised trials show significant cardiovascular event reduction in people with elevated triglycerides and high cardiovascular risk. At standard supplement doses (1 g/day), the evidence is less consistent. The dietary recommendation remains clear: oily fish (salmon, mackerel, sardines, anchovies, herring, trout) 2–3 times per week is a robust, food-first approach to obtaining cardiovascular-protective omega-3s. For those who cannot eat fish, algae-based DHA+EPA supplements provide the marine-form omega-3s from the same source that fish themselves obtain them.

High blood pressure (hypertension) is one of the most powerful modifiable cardiovascular risk factors, and diet is one of the most effective interventions to lower it. The DASH (Dietary Approaches to Stop Hypertension) diet was specifically designed to lower blood pressure through dietary change and has been validated in multiple randomised trials showing blood pressure reductions of 8–14 mmHg systolic — comparable in magnitude to a single antihypertensive medication.

The DASH diet emphasises vegetables, fruits, whole grains, low-fat dairy, lean proteins, legumes and nuts, while limiting sodium, red meat, sweets and sugary beverages. Sodium reduction is the most powerful single dietary lever for lowering blood pressure: reducing sodium from the typical Western intake of 3,500–4,000 mg/day to the recommended 1,500–2,300 mg/day reduces systolic blood pressure by 5–10 mmHg on average. Potassium has a complementary blood pressure-lowering effect (via different mechanisms), and increasing potassium intake from vegetables, fruit and legumes reinforces the sodium reduction benefit. Magnesium and calcium (both abundant in DASH-compliant foods) further contribute to blood pressure regulation. Alcohol also raises blood pressure: even moderate consumption (2 drinks/day) raises systolic blood pressure meaningfully, and elimination of alcohol has some of the most reliable blood pressure effects of any dietary change.

LDL cholesterol is the most directly causal of the established cardiovascular risk factors, and diet can lower LDL by a clinically meaningful 10–30% through targeted changes. Dietary cholesterol (from eggs and shellfish) has a much smaller effect on serum LDL than was previously believed, and the longstanding egg restriction advice has been substantially walked back. For most healthy individuals, eating one to two eggs daily has little impact on cardiovascular risk in the context of an otherwise healthy diet.

Soluble fibre is among the most reliably LDL-lowering dietary components. Beta-glucan from oats and barley (3 g/day), psyllium husk and pectin from apples and citrus all lower LDL cholesterol through bile acid sequestration in the gut. Plant sterols and stanols — found naturally in vegetable oils, nuts and seeds, and added to some margarines and yoghurts — block cholesterol absorption from the gut and lower LDL by 10–15% at intakes of 2–3 g/day. Replacing saturated fat with unsaturated fat (as discussed above) is another powerful LDL-reducing dietary change. Soy protein (25 g/day) has FDA recognition for LDL lowering, with typically a 4–6% reduction. Combining these approaches — the 'Portfolio Diet' developed by researcher David Jenkins — can achieve LDL reductions of 25–35%, entering territory that approaches statin-level effects for some individuals.

While much heart-health dietary advice focuses on what to add, what to remove matters equally. Ultra-processed foods — mass-produced items containing multiple additives, emulsifiers, flavour enhancers, preservatives and ingredients not found in domestic kitchens — are now strongly associated with increased cardiovascular risk, independent of their sodium, fat and sugar content. Recent large cohort studies suggest that each 10% increase in ultra-processed food contribution to the diet is associated with a 12% increase in cardiovascular disease risk.

Processed and red meat consumption is consistently associated with higher cardiovascular mortality in large meta-analyses. Processed meat (bacon, sausages, ham, salami, hot dogs) is particularly strongly implicated, likely due to its combined sodium, nitrite, saturated fat and advanced glycation end product content. Reducing processed meat to occasional consumption and replacing it with fish, poultry, legumes or plant protein sources has a reliable cardiovascular benefit. Sugary drinks and ultra-processed snack foods raise triglycerides, lower HDL and promote visceral fat accumulation. Refined carbohydrates more broadly — white bread, white rice, sugary cereals, commercial pastries — have replaced saturated fat as the dietary component most correlated with adverse cardiometabolic outcomes in contemporary diet research.