The Blood Type Diet Review: Fact or Fiction?

The blood type diet, also known as the blood group diet, was popularized by naturopathic doctor Peter D’Adamo back in 1996.

His book, Eat Right 4 Your Type, was a New York Times bestseller, has sold over 7 million copies, and is still popular today.

In this book, he claims that the optimal diet for any one individual depends on the person’s ABO blood type. That is, whether your blood type is Type A, B, AB or O.

It's an interesting theory, and there is strong evidence that people with certain blood types can have a higher or lower risk of some diseases.

However, there are no studies showing this has anything to do with diet. In fact, the only study to test this theory has shown it to be false.

In this study, researchers looked at almost 1,500 subjects on each of the four blood type diets, and documented several outcomes like waist circumference, blood pressure and insulin levels.

They found that adherence to either the A,B or O type diets was associated with some beneficial effects. Not surprising of course, as most diets tend to work in the beginning when people first begin to eat fewer calories overall, or avoid the worst indulgences. Plus each of the dietary patterns are healthy and would be a huge improvement for most people.

However, the big finding was that, the beneficial effects had nothing to do with an individual’s blood type. If a person followed the type A diet, they would see similar health effects regardless of whether they had A, B, AB or O type blood.

This just shows the dietary patterns are healthy, which explains why so many people swear that it works. But it would work equally well on someone with an ‘incompatible’ blood type.

So the main conclusion of the study was actually that although the eating patterns themselves are healthy, it has absolutely nothing to do with a person’s blood type.

Senior author Ahmed El-Sohemy, even said: "We can now be confident in saying that the blood type diet hypothesis is false".

Now the study was not perfect, and in research you can always find some flaw or weakness to point to if you disagree with the results. But given the lack of plausibility, this large study is sufficient to reject the blood type theory.

The burden of proof now falls on D'Adamo to show us otherwise- to show that is does indeed work, much like The Atkins corporation did.

And with over 7 million copies of the book sold, and millions of dollars since spent on developing and marketing related cookbooks, supplements, and even apps and software, it's very strange that his company have not yet invested in any good research to prove their own theory.

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Study mentioned in video:

[cricketkeedy]

This diet works great for me. My digestion works great now. I have no bloating anymore. I tried another blood type and I can't digest any foods on the other blood types. Many of my friends do this and also have improved their digestion and energy.

[kalenmcgruder]

I am on the blood type diet. It is a life change. I lost 72 pounds all over my body after starting the life change in. I couldn't fit nothing in my house. I have been doing this since 2011. I love the me I see.

[ACIMessentials]

I altered my eating habits due to the suggestions in the book and my health improved even further. I was already at my optimal weight, so I don't know that I lost weight, but to eliminate a few foods helped my health. I'm an A+, and I'd already been vegetarian for a very long time, but eliminating those few foods really did the trick. I think you can find someone who will attack anything that is good... especially if they have a competing product to sell.

[SaveDaFish]

Why do we need studies when we can just try it ourselves and see what works for us

[reginacarter]

I've been trying the diet so far for two weeks. As for my body I noticed a huge change in how I felt for the better. I have more energy and my allergies are already getting better. I was eating 80% healthy any way but once I started to use the avoid list there was a huge change. I plan on continuing as a life change and not a diet. I like feeling better:)

[arthurgonz]

The study was just for one month, it also shows a lot of arrogance from you to dismiss the theory based on only one study which even you said can be flawed

[leez]

Dont agree, i only managed to sort my allergies, lose weight and feel good when i started eating for my Type which is O. Finally it made sense why i cant handle grains especially corn and wheat.

[BikerMiceOne]

my wife is A and gets dizzy eating meat. so there must be some truth to this

[jjcrazi]

Kudos to you for making these. It's frustrating reading the comments sections full of scientifically illiterate statements and people who obviously haven't watched the video before making a comment. Thank you for your time and effort.

[zameer]

There's a lot of controversy surrounding the consumption of cow milk. Would be great if you could make a video. Thanks!

[haaskakuolleiden]

Just stumbled on this video, and after seing the amouth of personnal testimony and Ad Hominem attack, you can clearly see those ppl have no idea of the concept of Burden of Proof or any scientific methodology.

This "Matangaro Matangaro" dude is the worst tho, he's a perfect exemple of Dunning-Kruger effect, and take a popular feedback as empirical data. This is not how science work. If you want to compare the study showcased in the video, attack it with with an equialent or better protocol one's, not popular feedback.

[rodrigohernandezmijares]

¨The only study¨ has shown it to be false. Fuck, we need real scientists to do this educational videos not imitation Physicians called nutritionists.

[MaiNtive]

Finally

Critiquing a hypothesis is easy and arriving at a preconceived conclusion is no challenge at all - science is full of personally opinionated criticism masquerading as critical thinking

Studying the global phenomenon that is D'Adamo's BLOOD TYPE DIET across the cultural diversity of the planet experiencing ABO blood group based strategic lifestyle requires a robust culturally competent methodology that this pithy Highschool science project lacks

I'm open to best practice science because my health deserves the best

Until global science reports corroborate this lone piece of research then it exists only as a piece of poorly crafted criticism and not best practice science

Your support of its findings diminishes your trustworthiness

Be better
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Get best science to back up your opinions

Dude ... I'd remove this video to protect what little integrity I have left and wait for more science.

[metteholm]

For every superstition, that is debunked, we are freed from one portion of confusion.

[MaiNtive]

No one has ever examined the association between blood type based dietary patterns and healthy outcomes

That was a poorly crafted piece of public statement -

over 7 plus or minus million people have actually examined the association of their outcomes with their dietary lifestyle changes under Blood Group guidelines over a period of two plus decades ...

One pithy study does not negate D'Adamo's claims nor the weight of positive outcomes "experienced by the global public.

Best practice science requires best practice methodologies applied to highest standard data collection techniques and higher standard interpretative qualitative technique that corroborate a pattern of probability of likeliest conclusion.

The reports conclusion states "the favourable findings found were "independent" of the claims that benefits will result by following an ABO programme.

I would guarantee best science findings would show in fact the benefits are "co-dependent" on following D'Adamo's strategy

[MaiNtive]

Furthermore the report closes by stating "...the findings do not support the Blood-Type diet hypothesis."

So let's break it down...

D'Adamo's hypothesis suggests changing ones lifestyle and dietary patterns according to his strategic ABO hypothesis will result in benefits.

The study found favourable effects on some cardio metabolic markers

The researcher then by technique of qualitative interpretation wordsmiths the resulting benefits as being "independent" of the D'Adamo hypothesis

Which then leads to the final statement of non-support

This is in fact the poorest kind of science reporting

And your opinion piece here the poorest kind of pseudo professional public relations outreach

Please do better

In fact do best or don't do at all.

[mavisasamoah-clinicaldieti]

Very interesting, Please can you provide this information in writing instead of video??

[Hr.]

this video screams arrogance, i bet this guy never got diagnosed with shit in his life that he had to overcome. 😂