2013 major "Mediterranean diet with olive o... - Healthy Eating

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2013 major "Mediterranean diet with olive oil is good for you" retracted

andyswarbs profile image

If you watch youtube.com/watch?v=_JiKXdZ... (while it still exists) you will find a report on what was called a landmark study applauded by the New York Times and many more saying you could eat olives, olive oil, nuts, fish, wine etc - and that it is heart healthy!

The authors have now decided the paper was fundamentally flawed and have fully retracted the paper. My favourite take on the retraction is by Dr Pam Popper youtube.com/watch?v=KoDx040... which looks into the actual results - and shows no statistically significant benefits in the touted dietary improvements. Not only that but also the design of the research was not randomized, as claimed!

My advice - at least look at who is funding the research to see if there is any funding bias. In this instance the research was paid for by the olive oil industry!

Indeed this forum has been using this exact study to justify consuming olive oil. For instance healthline.com/nutrition/ex... says "Studies on the Mediterranean Diet show that it can help prevent heart disease. In one major study, it reduced heart attacks, strokes and death by 30% (15)." as touted by Authority Nutrition.

30% is a huge difference. And now this paper is retracted. All because the study was rigged and in fact there was NO statistical significance.

PS I am not saying that all industry funded science is bad science, but rather that it needs to by critically assessed for industry bias as well as any other tests for scientific validity.

16 Replies

Do you have a link to the actual retraction?

I'm not usually able to watch videos

andyswarbs profile image
andyswarbs in reply to benwl


Sorry benwl, I like to both read and watch different sources. That way my brain takes on the fuller scope of what is implied.

I'm going to do it again. But for anyone who likes videos here is one that takes you through step-by-step on how the study made itself look good. youtube.com/watch?v=cktwDEX...


a) compared a low-fat diet to two high-fat diets. In fact none of them were low fat, instead the three groups were all around 40% fat, with the low fat group being at 37%. Note the standard american diet has a fat level around 35%. My definition of low fat is 10%. According to this video all three diets are killers. If you truly want a low vs high fat comparison then don't compare three similar diets but compare against a whole-food plant-based diet at 10% fat.

b) it starts looking like it is a large study of 15,000 participants when in fact because of the flawed randomisation that drops to 7,500 at best.

c) the real story in this research is that the number of significant heart etc events is high regardless of what diet the participants followed.

benwl profile image
benwl in reply to andyswarbs

Thanks for the link and the summary.

I agree, lack of consistent terminolgy around terms like low fat, low carb etc makes everything much more confusing as well as providing scope for those that want to deliberately distort and obfuscate.

Hidden profile image
Hidden in reply to benwl

I second that, too. Some people are working, you know. ;)

>> In this instance the research was paid for by the olive oil industry!

IIRC, Nina Teicholz covered this, and the exaggerated benefits of the Mediterranean Diet, in 'the big fat surprise'. That was 4-5 years ago.

To be fair, it depends what you're comparing it with. The Med Diet probably is better than, say, the McDonalds and Pizza Hut diet.

Jerry profile image
JerryAdministrator in reply to TheAwfulToad

Probably LOL...😊

That's exactly my point: comparing what with what. This is why the adventist 2 study is so relevant. For the first time you have a large cohort studied over many years who all personally strive for health of whom a significant number actually follow something close to a whole food plant based diet whereas others are vegetarian and others eat meat.

Hidden profile image
Hidden in reply to andyswarbs

But as you say, you avoid soya and use soy sauce. You cannot expect people to do as you do. Let people enjoy olive oil. At least, it isn't meat or someone else said, it's not vegan junk food/packaged vegan food. You visit Pizza Hut whilst you claim you lead a healthy vegan food lifestyle. People want flexi-dietary style as much as you do, not black & white diet where they can't eat this or eat that. I don't see any point of any claim that you will die young unless you stop eating this or that. There is no point in preaching.

andyswarbs profile image
andyswarbs in reply to Hidden

I have no problem with people eating something because they enjoy it.

Many people smoke because they enjoy the experience, despite evidence of it being unhealthy. Because of changes in society it would be very difficult for someone to get the impression that smoking is a healthy occupation.

That is not the same with foods. Most people eat / drink these because they enjoy and because they are addicted. But if they are being deluded into thinking it is somehow healthy for them by biased science...

Cooper27 profile image

I was reading though, that the pioppi diet (a type of Mediterranean) is based on the diet of people who live in Pioppi, where life expectancy is typically around 100. If we look at population studies like that, is it not a good source, free from outside influence?

At the end of the day, companies and industries will only fund studies where there is a chance it will generate enough income to make it worthwhile. The studies often start with a hunch, and just need something to back it up. For example, I know someone who was given funding to research the health benefits of curry, and funding came from a curry sauce maker. The study will obviously focus only on curry, because a curry sauce maker has no desire to know whether, say, eggs are good for you or not. It will be a similar reason that olive oil funded research into the Mediterranean diet. With the prevalence of go fund me though, perhaps crowd sourcing would allow vegans to fund research into the health benefits of a vegan diet.

andyswarbs profile image
andyswarbs in reply to Cooper27

Pioppi is an interesting anecdote - please correct me if I am wrong - which there is no serious research. For those who do not know Pioppi is a beautiful seaside town in Southern Italy. It was the home of Ancel Keys for many years, and was the springbed from which the term Mediterranean Diet came.

Like so much of life terms change in their definition depending who is speaking. To many whole food plant based doctors the Med Diet works because of the focus on plants. Whereas Ancel Keys et al focus on olive oil, fish and meat.

Arguably the most authoritative definition of Med Diet is mediterradiet.org/nutrition.... Indeed this interpretation is supported by the British Nutrition Foundation in their statement on the Poppi diet at nutrition.org.uk/nutritioni.... Where they specifically states, "The advice to cut out starchy carbohydrates such as bread pasta and rice is inconsistent with a Mediterranean dietary pattern, which typically includes these foods (mostly wholegrains) at every meal."

What there is research proving is that people who eat less live longer. Traditionally people of Pioppi were very poor and struggled to get enough food to live on. This research paper ncbi.nlm.nih.gov/pmc/articl... states, "dietary restriction of proteins or other individual nutrients (DR), with respects to carbohydrates, produces an effect on longevity independent on that of CR." (CR=Calorie Restriction)

That's an interesting possibility. The Med Diet is not (as diets go) a particularly bad one, although I can certainly believe it's not miraculously better (in life-expectancy terms) than any other diet, for the simple reason that humans thrive on pretty much anything. If you had to sum up the entire body of dietary research in one sentence, it would be what your grandmother told you: "don't stuff your face with sweets and junk and you'll probably be OK". Granny could have saved a lot of governments a few billion $, I reckon.

So I wonder if this is all "coming out" simply because someone has some obscure dispute with - who knows? - the Olive Oil industry. For example, it could be that the USDA is worried that American vegetable-oil sales might be negatively affected by all the recent experiments showing that unsaturated fats aren't so good for you after all. This sort of thing would be a good way to redress the balance. Not saying that actually happened here, but it wouldn't be the first time the USDA have produced a slew of bad science to support US agricultural policy.

Hi andyswarbs

How very interesting!

I totally agree that much research can be started from a 'selection bias' leaving a false result!

The blood sugar diet which I'm reading about says 'drizzle Olive oil' on certain cooking or in sauces.

Whilst I use it for cooking like most things, used in low moderation I'm sure it's fine. But overused & I dare say it's a problem!

Thanks for your post.

A great reminder to be cautious. :)

Olive oil is, and always has been, a luxury good. Nobody has yet figured out a way to make it cheaply - it's just inherent in the nature of the thing. So it seems likely that nobody has ever consumed it in large quantities.

AFAIK there's no specific evidence that it's harmful, as such. However I don't see any need to smother everything in a very expensive ingredient that might not have the correct taste profile for the thing you're preparing.

I prefer the old quip to the effect "don't explain with a conspiracy what can be explained by incompetence."

I think what happened here is the researchers screwed up - experimental design and analysis is hard with plenty of pitfalls for the unwary, and they made mistakes. The scientific process worked, the mistakes were spotted and corrected.

You've had an interesting life :)

It sounds like you know what a proper Mediterranean diet is supposed to look like?

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