Whole-food plant-based: the heart diet with big claims and small studies.
Vegan, no added oil, nothing processed. Two American doctors built programmes on it for people with heart disease and reported that blocked arteries got wider. Impressive. Also: very small studies. Here's the honest version.
The short version
- What it is
- Only whole plant foods: vegetables, fruit, whole grains, beans. No animal products, no added oil, nothing refined.
- Good for
- Lowering cholesterol. In small studies of heart patients, slowing or partly reversing artery disease, as part of a full lifestyle programme.
- Bad at
- Being easy. Almost nobody eats like this without serious support. B12 is a must.
- Evidence
- Moderate for heart patients, based on small trials and uncontrolled case series.
- Our take
- A medical diet. If you have heart disease and want to try it, do it with your cardiologist, not with us.
What the whole-food plant-based diet actually is
Start with vegan: no meat, fish, dairy or eggs. Then take away everything processed: no white flour, no sugar, no vegan junk food, and, the part that surprises people, no added oil. Not even olive oil. What's left is vegetables, fruit, whole grains, beans, lentils, and in some versions a few nuts and seeds.
Two names dominate. Dean Ornish, a Californian doctor, combined a very low-fat vegetarian diet with exercise, stress management and group support in a programme for heart patients.1 Caldwell Esselstyn, a surgeon at the Cleveland Clinic, counselled heart patients to cut out meat, fish, dairy and added oil completely.3 Both programmes became famous through books and documentaries. Both were designed for sick people, not for someone who wants to fit into their jeans.
How it works in your body
This diet is extremely low in saturated fat and contains zero dietary cholesterol, because both come mainly from animal foods. It's also very high in fibre. The result is usually a steep drop in LDL ("bad") cholesterol, the main driver of plaque in your arteries. Trials of vegetarian and vegan diets in general show that drop clearly.4
The no-oil rule also makes the food much less calorie-dense, so people tend to lose weight without counting. Vegan diets led to more weight loss than meat-containing diets in a meta-analysis of trials.5
Lower cholesterol, lower weight, lower blood pressure: that's the mechanism. No magic, just a lot of everything that helps at once.
What you eat, what you don't
Eat
- Vegetables, a lot of them, especially leafy greens
- Beans, lentils, chickpeas, peas
- Whole grains: oats, brown rice, barley, wholegrain bread
- Potatoes and sweet potatoes
- Fruit, whole, not juiced
- Herbs, spices, vinegar, lemon for flavour
- A B12 supplement
Forget it
- Meat, fish, dairy, eggs
- All added oils, including olive oil
- Sugar, white flour, white rice
- Vegan junk food, vegan cheese, plant burgers
- Fried food of any kind
- In the strictest versions: nuts, avocado and coconut
Alcohol on a whole-food plant-based diet
OK
- Water, sparkling water with lemon
- Herbal tea, green tea, black coffee
- Any alcohol only after your cardiologist says yes
Out
- Beer, wine and spirits as a habit
- Cocktails, liqueurs, sweet mixers
- "Red wine for the heart"
50 Club: none. This is a medical diet for people with heart disease.
If your heart is the reason you're eating this way, alcohol is a question for your doctor, not for a website. The World Health Organization says no safe level of drinking has been shown.8 All the details are in our alcohol guide.
What it's good for, with proof
Artery disease that went backwards, in a small trial
In Ornish's Lifestyle Heart Trial, 48 people with heart disease were randomised: 28 to the full programme (very low-fat vegetarian diet, exercise, stress management, group support) and 20 to usual care. After one year, artery narrowing had partly reversed in the programme group, measured on angiograms.1 After five years, the programme group showed more regression, while the control group's disease kept getting worse and had more than twice as many cardiac events.2
Honesty corner: only 35 people completed the five-year follow-up. And diet was one of four changes at once, so nobody can say how much of the effect was the food.
Few new heart events among people who stuck with it
Esselstyn followed 198 heart patients who received plant-based nutrition counselling. Of the 177 who stuck with it, one had a stroke during follow-up, a recurrence rate of 0.6%.3 That sounds incredible. But this was a case series: no randomisation, no control group, and the people who stuck to the diet may have differed from those who didn't in many other ways.
Lower cholesterol, every time
Across 30 randomised trials, vegetarian and vegan diets lowered total cholesterol, LDL cholesterol and apolipoprotein B.4 A whole-food, no-oil version is the strictest end of that range.
The uncomfortable truth
"This diet is proven to reverse heart disease." It's been shown in very small studies, combined with other lifestyle changes, under close medical supervision. The trial had 48 people; the case series had no control group.13 That's promising, not proof. Nobody should stop their heart medication because of a documentary.
"Olive oil is bad for you." The no-oil rule is specific to these programmes. In large trials of people at risk, the Mediterranean diet with extra olive oil cut heart attacks and strokes.11 Different diets, different evidence; both can be right for different people.
The risks
- Vitamin B12 deficiency. A vegan diet without supplements or fortified foods is a known cause of B12 deficiency,6 which can cause nerve damage that is sometimes permanent.7 Take B12. Every day.
- Other gaps. Iodine, calcium, iron, selenium and vitamin D are easy to miss without animal foods; the NHS recommends fortified foods or supplements.9 Without oil, nuts or fish, omega-3 needs thought too: ground flax and chia help.
- Too few calories. Very high fibre and very low fat can fill you up before you've eaten enough, a real problem for older or underweight people.
- Medication changes. If your cholesterol, blood pressure or blood sugar drop fast, your doses may need adjusting. That's why this needs a doctor.
- It's very hard to keep up. No oil, no cheese, no eating out. Most people need a lot of support to stick with it.
Allergies: watch the staples
With no animal foods and no oil, the plan leans on legumes, grains, soy and seeds. Several are major allergens.
| Staple | Allergen (EU list of 14)10 | Swap |
|---|---|---|
| Tofu, tempeh, soy drink, edamame | Soy | Lentils, beans, chickpeas |
| Wholegrain bread, barley, spelt, oats (often contaminated) | Cereals containing gluten | Brown rice, quinoa, buckwheat, certified gluten-free oats |
| Walnuts, almonds (in less strict versions) | Tree nuts | Ground flax, chia, pumpkin seeds |
| Peanut butter | Peanuts | Mashed beans, sunflower seed butter |
| Hummus, tahini | Sesame | White bean dip with lemon |
| Lupin-based products | Lupin | Pea-based products |
| Soups and stocks | Celery | Fennel, carrot, onion |
Don't do whole-food plant-based if you…
- have heart disease and haven't talked to your cardiologist first
- take blood pressure, cholesterol, diabetes or blood-thinning medication, without your doctor monitoring you
- are pregnant, breastfeeding, a child or a teenager, without a specialist dietitian
- are underweight, frail or have trouble eating enough
- have ever had an eating disorder
- have kidney disease: the potassium in all those plants may need limiting
Healthen me asks about all of these and gives you a different plan if any apply.
How we use whole-food plant-based in your plan
We don't. This is a medical diet. If you tell Healthen me you have heart disease, we suggest talking to your cardiologist and give you a gentle plan without fasting until they've had a say. If they put you on an Ornish- or Esselstyn-style programme, follow theirs, not ours.
What we do borrow: whole foods over processed ones, beans and lentils as a main protein, vegetables in serious quantities. That's in every plan anyway. If you want to eat fully plant-based without a medical reason, the vegan filter does that, with olive oil allowed and B12 checked. If cholesterol is your concern, the Portfolio diet is the better-tested route.
This article is general information, not medical advice. If you have a medical condition or take medication, talk to your doctor before changing how you eat.
Sources
- Ornish D et al. Can lifestyle changes reverse coronary heart disease? The Lifestyle Heart Trial. The Lancet 1990;336(8708):129–133. doi.org/10.1016/0140-6736(90)91656-U
- Ornish D et al. Intensive lifestyle changes for reversal of coronary heart disease. JAMA 1998;280(23):2001–2007. doi.org/10.1001/jama.280.23.2001
- Esselstyn CB Jr et al. A way to reverse CAD? Journal of Family Practice 2014;63(7):356–364b. pubmed.ncbi.nlm.nih.gov/25198208
- Koch CA, Kjeldsen EW, Frikke-Schmidt R. Vegetarian or vegan diets and blood lipids: a meta-analysis of randomized trials. European Heart Journal 2023. doi.org/10.1093/eurheartj/ehad211
- Huang RY, Huang CC, Hu FB, Chavarro JE. Vegetarian diets and weight reduction: a meta-analysis of randomized controlled trials. Journal of General Internal Medicine 2016;31(1):109–116. doi.org/10.1007/s11606-015-3390-7
- NHS. Vitamin B12 or folate deficiency anaemia: causes. nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/causes
- NHS. Vitamin B12 or folate deficiency anaemia: complications. nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/complications
- WHO Regional Office for Europe. No level of alcohol consumption is safe for our health. News release, 4 January 2023. who.int/europe/news/item/04-01-2023-no-level-of-alcohol-consumption-is-safe-for-our-health
- NHS. The vegan diet. nhs.uk/live-well/eat-well/how-to-eat-a-balanced-diet/the-vegan-diet
- Regulation (EU) No 1169/2011 on food information to consumers, Annex II (the 14 allergens). eur-lex.europa.eu/eli/reg/2011/1169/oj
- Estruch R et al. Primary prevention of cardiovascular disease with a Mediterranean diet supplemented with extra-virgin olive oil or nuts. New England Journal of Medicine 2018;378:e34 (retracted 2013 paper republished). doi.org/10.1056/NEJMoa1800389