68 Harley Street London, W1G 7HE · Main Office
Also at Cromwell & Syon Bishops Wood · Multiple Locations
0203 9838 001 Call for Appointments
jessica@oneheartclinic.com Rapid Response to Enquiries
Patient Guide
14 minute read Diet & Heart Health
What you eat every day is one of the most powerful tools you have for protecting your heart. This guide covers optimal meals, the science of macronutrients, evidence-based superfoods, and the most popular dieting approaches — so you can make informed choices.
D
Key Takeaways
What the evidence tells us
- The Mediterranean diet reduces major cardiovascular events by up to 30% — the strongest dietary evidence we have (PREDIMED trial, NEJM 2013).
- Most adults need 1,800–2,500 kcal per day; eating 300–500 kcal below your daily need produces steady, sustainable weight loss.
- Protein, healthy fats, and complex carbohydrates all have a role — no single macronutrient causes heart disease when eaten in appropriate amounts.
- Oily fish, extra virgin olive oil, nuts, berries, dark leafy greens, and legumes are the most evidence-backed foods for cardiovascular protection.
- Keto, intermittent fasting, and plant-based diets can all be effective — the best diet is the one you can sustain long term.
- Ultra-processed food, excess sugar, salt above 6g/day, and trans fats are the greatest dietary threats to heart health.
The evidence for diet and the heart
30%
Reduction in major cardiovascular events
Mediterranean diet vs low-fat control
PREDIMED Trial, NEJM 2013
PREDIMED Trial, NEJM 2013
72%
Fewer recurrent heart attacks
Mediterranean diet with ALA vs low-fat diet
Lyon Diet Heart Study, Lancet 1999
Lyon Diet Heart Study, Lancet 1999
3×
Higher cardiovascular risk from ultra-processed food
Top quartile UPF intake vs lowest
BMJ meta-analysis 2024
BMJ meta-analysis 2024
Why diet matters so much
Food is medicine — and poison
Every meal either nudges your cardiovascular system towards health or away from it. The accumulated effect of thousands of daily food choices over decades determines your blood pressure, cholesterol levels, blood sugar regulation, body weight, and systemic inflammation — all major drivers of heart disease.
The good news is that dietary change delivers measurable improvements quickly. Blood pressure can fall within weeks of reducing salt. LDL cholesterol responds to saturated fat reduction within a month. The heart is remarkably responsive to what you eat.
This guide is designed to cut through conflicting headlines and give you a clear, evidence-based framework — not a rigid diet plan, but an understanding of the principles that will serve you for life.
A note on individual variation. Genetics, gut microbiome, activity levels, and existing health conditions all influence how you respond to food. These recommendations represent the best available population evidence — your cardiologist can give guidance tailored to your specific situation.
D
Nutrition fundamentals
Calories, macros & what you actually need
Understanding your energy needs and macronutrient balance is the foundation of a healthy diet — before any specific foods or meal plans.
2,000 kcal
Average adult woman
Sedentary to moderately active. Reduce by 300–500 kcal for steady weight loss of 0.5 kg/week. Requirements increase during pregnancy and breastfeeding.
2,500 kcal
Average adult man
Sedentary to moderately active. Reduce by 500 kcal for around 0.5 kg/week loss. Physically active men may need 2,800–3,200 kcal to maintain weight.
45–55%
Carbohydrates
Carbohydrates are your body's preferred fuel source. The key is quality over quantity — the type of carbohydrate matters far more than the total amount.
- Choose: oats, quinoa, sweet potato, lentils, whole grain bread and pasta, brown rice, legumes
- Limit: white bread, white rice, sugary cereals, fruit juice, biscuits, cakes
- Aim for at least 30g of fibre daily — most adults eat fewer than 18g
- Free sugars (added sugar, honey, syrups) should be below 30g/day (WHO guidance)
25–35%
Fats
Fat is not the enemy. The type of fat is what matters. Unsaturated fats actively protect the heart; saturated and trans fats raise LDL cholesterol and increase risk.
- Choose: extra virgin olive oil, oily fish, avocado, nuts, seeds
- Limit: red meat, butter, full-fat dairy, coconut oil, palm oil (saturated fats — keep below 10% of total calories)
- Avoid: hydrogenated oils and trans fats (found in some processed snacks and margarines)
- Omega-3 fatty acids (EPA & DHA) in oily fish are particularly cardioprotective
20–30%
Protein
Protein preserves muscle mass, supports satiety, and is essential for tissue repair. Most adults need 0.8–1.2g per kg of body weight per day; active individuals need more.
- Choose: oily fish, chicken, turkey, eggs, Greek yogurt, legumes, tofu, tempeh, edamame
- Limit: red meat to 1–2 times per week (BHF guidance)
- Avoid: processed meats (bacon, salami, hot dogs) — classified Group 1 carcinogen by IARC and linked to CV risk
- Plant proteins also provide fibre and phytonutrients — diversifying protein sources is ideal
Your daily meals
Building an optimal day of eating
A structured approach to each meal — what to prioritise, what to moderate, and what to replace. These are frameworks, not rigid prescriptions.
07:00 – 09:00
Breakfast
Start with protein and slow-release carbohydrates. A protein-rich breakfast reduces hunger hormones (ghrelin) for hours and prevents mid-morning energy crashes that lead to poor food choices.
Best choices
- Overnight oats with berries, walnuts & a teaspoon of flaxseed
- Poached or scrambled eggs on whole grain sourdough
- Smoked salmon with avocado on rye bread
- Full-fat Greek yogurt with mixed berries and a drizzle of honey
- Porridge (whole rolled oats) with banana and almond butter
Replace or avoid
- Sugary breakfast cereals (often 30–40% sugar by weight)
- White toast with jam or marmalade — rapid blood sugar spike
- Pastries, croissants, breakfast biscuits
- Fruit juice — no fibre, high in free sugars
Target 400 – 550 kcal
12:00 – 14:00
Lunch
Make this your largest or second-largest meal. Aim for half the plate to be non-starchy vegetables, one quarter lean protein, and one quarter whole grain carbohydrate.
Best choices
- Large salad with grilled chicken, chickpeas, feta, olive oil & lemon
- Lentil soup with a slice of whole grain bread
- Grilled salmon or mackerel with roasted vegetables and quinoa
- Mediterranean bowl — hummus, falafel, tabbouleh, olives, pomegranate
- Whole grain wrap with tuna, avocado, spinach, and tomato
Replace or avoid
- Meal-deal sandwiches on white bread with crisps
- Fast food burgers, wraps, or fried chicken
- Ready meals — typically very high in salt and saturated fat
- Sugary drinks alongside meals — raises postprandial glucose sharply
Target 550 – 700 kcal
18:00 – 20:00
Dinner
Eat dinner at least 2–3 hours before bed to allow digestion. Keep portions moderate in the evening — metabolic rate is lower and calories are more readily stored.
Best choices
- Baked sea bass or mackerel with roasted Mediterranean vegetables and olive oil
- Chicken and vegetable stir-fry with brown rice or noodles
- Lentil dhal or bean chilli with whole grain rice
- Lean lamb or beef (1–2×/week max) with plenty of vegetables
- Vegetable curry with chickpeas, spinach and a small portion of basmati
Replace or avoid
- Large pasta or rice portions as the main component
- Creamy sauces made with butter, double cream or coconut milk
- Eating the largest meal of the day late in the evening
- Alcohol as a regular accompaniment — contributes calories and raises triglycerides
Target 500 – 650 kcal
Snacks (200–300 kcal budget): A small handful of mixed nuts, a piece of fruit with nut butter, a boiled egg, or carrot sticks with hummus. Avoid processed snack bars, crisps, and biscuits. Snacking is not inherently harmful — the quality of snacks is what matters.
Evidence-backed foods
Ten superfoods for the heart
"Superfood" is not a medical term, but these ten foods have substantial, consistent clinical evidence supporting their cardiovascular benefit. Including several of them daily is one of the most impactful dietary changes you can make.
F
Oily Fish
Salmon, mackerel, sardines, trout, herring. Rich in EPA & DHA omega-3 fatty acids — reduce triglycerides, lower inflammation, and reduce fatal arrhythmia risk.
2–3 portions/weekB
Berries
Blueberries, strawberries, raspberries. Anthocyanins reduce blood pressure, improve endothelial function, and lower oxidised LDL. Daily consumption linked to 32% lower MI risk.
Daily portionG
Dark Leafy Greens
Spinach, kale, rocket, watercress. High in dietary nitrates (lower blood pressure), folate (reduces homocysteine), magnesium, and vitamin K for healthy arterial walls.
Large portion dailyN
Walnuts & Almonds
Walnuts are the only nut rich in ALA omega-3. Almonds lower LDL cholesterol. A 30g daily handful reduces CV risk by ~14% (Nurses' Health Study).
30g / small handfulO
Extra Virgin Olive Oil
The cornerstone of the PREDIMED trial. MUFA and polyphenols (hydroxytyrosol, oleocanthal) reduce inflammation, LDL oxidation, and platelet aggregation.
4+ tbsp/day in PREDIMEDC
Dark Chocolate (≥70%)
Flavanols (epicatechin) lower blood pressure, improve endothelial function, and reduce platelet activation. A 20–30g square 3–5x/week is the sweet spot.
≥70% cocoa onlyA
Avocado
Rich in oleic acid (MUFA), potassium (more than bananas), and fibre. Daily consumption associated with lower LDL and higher HDL in RCT data.
½–1 per dayL
Legumes
Lentils, chickpeas, black beans, kidney beans. 4+ servings/week reduces coronary risk by 22%. Soluble fibre lowers LDL; low glycaemic index stabilises blood sugar.
4+ servings/weekG
Garlic
Allicin (released on crushing) lowers systolic blood pressure by ~5 mmHg, reduces total cholesterol, and has mild antiplatelet effects. Raw or lightly cooked is most potent.
1–2 cloves dailyT
Green Tea
EGCG catechins lower LDL, reduce blood pressure, and improve endothelial function. 3–4 cups/day associated with 26% lower CHD risk (Japanese prospective cohort data).
3–4 cups dailyPopular approaches
Diet plans — what the evidence shows
There is no single "best" diet — different approaches suit different people. What they all share when effective: they reduce ultra-processed food, improve food quality, and create some degree of caloric deficit. Here is an honest assessment of the most popular plans.
Strongest Evidence
Mediterranean Diet
Most cardiovascular evidence of any dietary pattern
30%
fewer major CV events
(PREDIMED, NEJM 2013)
(PREDIMED, NEJM 2013)
Abundant vegetables, fruit, whole grains, legumes, nuts, olive oil as the primary fat, oily fish 2–3×/week, moderate dairy and eggs, minimal red meat, and moderate red wine. No calorie restriction — it is a pattern, not a prescription.
- Most sustainable long-term dietary pattern in research
- Reduces inflammation, blood pressure, LDL, and blood sugar
- Reduces risk of Type 2 diabetes and dementia as well as heart disease
- Flexible — no foods are banned
DASH Diet
Designed specifically for blood pressure control
11
mmHg reduction
in systolic BP (hypertensive patients)
in systolic BP (hypertensive patients)
High in potassium (fruit, vegetables, dairy), low in sodium (below 2,300 mg/day), low in saturated fat. Originally developed for people with hypertension but beneficial for all.
- 8–10 portions of fruit and vegetables daily
- Low-fat dairy for calcium and potassium
- Whole grains, nuts, lean protein
- No more than 6g salt per day (NHS guidance)
Ketogenic Diet
Very low carbohydrate (<50g/day), high fat
5–10%
of daily calories from
carbohydrates (strict keto)
carbohydrates (strict keto)
Forces the body into ketosis — burning fat as fuel instead of glucose. Effective for rapid initial weight loss (partly water weight). Can improve triglycerides and blood sugar. However, cardiovascular effects depend heavily on the quality of fats chosen.
- Strong short-term evidence for weight loss and glycaemic control
- Reduces triglycerides and raises HDL in most studies
- LDL effect is variable — rises in some, falls in others
- Difficult to sustain; requires careful electrolyte management
Caution: If saturated fat (butter, cheese, fatty meat) forms the bulk of fat intake on keto, LDL-C can rise significantly. Choose olive oil, avocado, nuts, and oily fish as the primary fat sources.
Plant-Based Keto
Low carb without the saturated fat concerns
Best
of both worlds for
LDL and weight control
LDL and weight control
Removes the cardiovascular downside of standard keto by eliminating animal saturated fat. Fat comes from avocado, olive oil, nuts, seeds, and coconut products in moderation.
- Protein from tofu, tempeh, edamame, hemp seeds, seitan, lupini beans
- Fats from avocado, EVOO, walnuts, almonds, flaxseed, chia, hemp
- Carbs limited to non-starchy vegetables: leafy greens, broccoli, courgette, peppers
- Lowers LDL-C while still enabling ketosis — the ideal keto approach for cardiac patients
Intermittent Fasting 16:8
Eat within an 8-hour window, fast for 16 hours
3–8%
body weight loss
over 8–24 weeks in trials
over 8–24 weeks in trials
For example, eat between 10am and 6pm, fast overnight. Works primarily by reducing the window of opportunity for eating, leading to a natural caloric deficit. Also improves insulin sensitivity and promotes autophagy (cellular repair).
- No calorie counting required
- Reduces fasting insulin and blood sugar
- Evidence for modest improvements in blood pressure and LDL
- Works well combined with Mediterranean food choices within the eating window
Not suitable for patients with Type 1 diabetes, those on insulin or sulfonylureas, or anyone with a history of eating disorders. Check with your doctor if on cardiac medications.
The 5:2 Diet
5 normal days, 2 days restricted to 500–600 kcal
5:2
shown equivalent to
daily calorie restriction (CALERIE trial)
daily calorie restriction (CALERIE trial)
Popularised by Dr Michael Mosley. On two non-consecutive fast days, eat one small meal of 500 kcal (women) or 600 kcal (men). The remaining five days you eat normally without restriction.
- Easier for many people than daily caloric restriction
- Reduces fasting glucose, triglycerides, and waist circumference
- The DiRECT trial (800 kcal/day) showed remission of Type 2 diabetes in 46% at 1 year
- Fast days work best with high-protein, high-fibre foods to manage hunger
The same cautions apply as 16:8 — unsuitable for patients with diabetes on insulin, sulfonylureas, or those with a history of disordered eating.
At a glance
Food choices: eat more, less, or avoid
A practical framework for your weekly shopping and meal choices. These recommendations align with British Heart Foundation and European Society of Cardiology guidelines.
Eat Freely Prioritise these foods daily
- All non-starchy vegetables (unlimited)
- Leafy greens — spinach, kale, rocket
- Legumes — lentils, chickpeas, beans
- Extra virgin olive oil
- Oily fish — salmon, mackerel, sardines
- Berries — blueberries, strawberries
- Nuts and seeds — walnuts, almonds, flaxseed
- Whole grains — oats, quinoa, brown rice
- Avocado
- Herbs and spices (potassium-rich, anti-inflammatory)
- Water, green tea, black coffee (in moderation)
Eat in Moderation Include but keep portions sensible
- Lean red meat — 1–2× per week maximum
- Full-fat dairy — cheese, butter, cream (small amounts)
- Eggs — evidence supports up to 7 per week for most people
- White rice and white pasta — larger portions spike glucose
- Fruit — whole fruit is healthy; 2–3 portions daily is appropriate
- Potatoes — white potatoes are high GI; sweet potato is better
- Red wine — up to 1 glass/day for women, 1–2 for men (if at all)
- Dark chocolate ≥70% — 20–30g several times per week
- Bread — whole grain is far preferable to white
Limit or Avoid These increase cardiovascular risk
- Ultra-processed food — packaged snacks, ready meals, fast food
- Processed meats — bacon, salami, hot dogs, sausages
- Sugary drinks — cola, fruit juice, energy drinks, flavoured coffees
- Trans fats — hydrogenated oils in some margarines and pastry
- Added sugar — biscuits, cakes, sweets, sweetened cereals
- Excess salt — aim below 6g/day; read labels carefully
- Deep-fried foods — high oxidised fat content
- Heavy alcohol — more than 14 units per week (UK guidelines)
- Palm oil and coconut oil in large quantities (saturated fat)
Making it practical
Ten changes that make a real difference
These are the most impactful, evidence-supported dietary changes for cardiovascular health — ranked roughly by size of effect.
01
Switch to extra virgin olive oil
Replace butter, sunflower oil, and vegetable spreads with EVOO for all cooking and dressing. This single change replicated a significant portion of the PREDIMED benefit. Use generously — aim for 2–4 tablespoons per day.
02
Eat oily fish twice a week
Salmon, mackerel, sardines, or trout. The omega-3 fatty acids (EPA and DHA) reduce triglycerides, lower inflammation, and reduce the risk of fatal cardiac arrhythmias. Oily fish is more effective than fish oil supplements.
03
Fill half your plate with vegetables
Non-starchy vegetables are the most nutrient-dense, calorie-sparse foods available. Make them the largest portion of every meal rather than an afterthought. Variety of colour ensures a wide range of antioxidants and phytonutrients.
04
Eliminate sugary drinks
Regular sugar-sweetened drinks are one of the strongest dietary risk factors for metabolic syndrome and Type 2 diabetes. Replacing cola, fruit juice, and flavoured coffees with water, green tea, or black coffee has an outsized effect on caloric intake and blood sugar.
05
Replace processed meat with fish, chicken, or legumes
Processed meat (bacon, sausages, salami, ham) is classified as a Group 1 carcinogen and is consistently associated with increased cardiovascular mortality. Even small reductions make a measurable difference at population level.
06
Eat a small handful of nuts every day
30g of mixed nuts (walnuts, almonds, Brazil nuts, cashews) daily is associated with a 14% reduction in cardiovascular risk. They are calorie-dense but not associated with weight gain in trials — the satiety they provide compensates.
07
Reduce salt to below 6g per day
Most adults consume 8–10g of salt daily. The majority comes not from the salt shaker but from bread, processed food, cheese, and sauces. Read labels: more than 1.5g salt per 100g is high. Reducing salt lowers blood pressure within weeks.
08
Choose whole grain over refined grains
Whole grain bread, pasta, rice, and oats have a substantially lower glycaemic index than their white equivalents, contain fibre that lowers LDL cholesterol, and are associated with reduced cardiovascular and all-cause mortality in meta-analyses.
09
Eat more legumes
Lentils, chickpeas, black beans, kidney beans, and edamame are the most underused cardiovascular foods in Western diets. High in soluble fibre (lowers LDL), plant protein, folate, potassium, and magnesium. Replace one meat meal per week with a legume-based dish initially.
10
Stop buying ultra-processed food
The most powerful dietary intervention is the one that doesn't happen — if it isn't in the house, it cannot be eaten. Ultra-processed food (ready meals, crisps, snack bars, fast food) is the single greatest dietary driver of cardiovascular disease in the modern world. Changing your shopping habits changes your diet permanently.
Related guides
Continue your reading
Diet works best as part of a comprehensive heart health strategy. These guides cover the lifestyle factors that complement dietary change.
Ready to discuss your heart health?
A cardiology consultation with Dr Nijjer includes a review of your lifestyle, diet, and risk factors — giving you a personal plan rather than general guidance.
Book a ConsultationMedical disclaimer. This page provides general educational information about diet and cardiovascular health and does not constitute personal medical advice. Individual nutritional needs vary depending on existing health conditions, medications, and metabolic factors. Some dietary changes — particularly fasting protocols, ketogenic diets, and high-fibre approaches — may interact with medications including warfarin, insulin, and antihypertensives. Always discuss significant dietary changes with your cardiologist or GP before starting.