Should you give the Blood Type Diet a try?

Should you try the Blood Type Diet?

The Blood Type Diet (BTD) is not just a diet, it’s the second genetics-based (a.k.a., “nutrigenomics-based”) diet ever to be devised. The first of course was in 1954 when Bickel, Hickmans and Gerrard published a paper that explained how they created a new type of diet that was low enough in the amino acid phenylalanine to be effective for those suffering from phenylketonuria. And just like that, nutrigenomics was born. It has saved many lives since. Then, in the 1970s Dr. James D’Adamo was the second one as he invented the Blood Type Diet (see book: One Man’s Food, 1980), which his son Dr. Peter D’Adamo (and yours truly, and others) further refined. Yes, it all started in the 1970s with D’Adamo Sr.’s initial research and findings, and his son’s significant revisions and additions which included such novel concepts as nonsecretor dietary modifications, epigenetic modifiers (SWAMI), and starting in 2015, full genetic analysis that analyzed much more than just the blood type-associated genes (4yourtype.com; www.datapunk.net)

According to the BTD, eating and avoiding certain foods based on your blood type can help you be healthier, lose weight, manage chronic disease, and have an overall impact on quality of life and longevity. The diet has not been proven to work for everyone, but that’s where the secretor dietary modifications and other genetic variants come into play. The diet works, it’s just that the Dr. D’Adamos were ahead of their time, and recent nutrigenomics, metabolomics, and microbiome discoveries have in many ways lent credence to quite a few of the biological aspects of the BTD. I have not met James yet, but Peter is a good personal friend and has been my mentor for over a quarter century now. I can tell you without a shadow of a doubt that he is a bonified medical and health genius, incorporating many new concepts into the existing field of naturopathic medicine, and had essentially the wellness world upside down when he published his first New York Times bestseller, Eat Right 4 Your Type.

 In the years since Dr’s D'Adamo introduced the BTD, several minor, poorly-conducted studies have tried to assess whether the diet actually works, but none of them have proved or disproven any clear link differentiating the different blood types according to diet and health. However, the amount of circumstantial and corroborative data is actually stunning, for all but the most obtuse scientists (and those who are just “BTD haters” and will never change). Still, the diet’s focus on healthy foods has shown benefits for many who have tried it, so much so that it has been translated into an amazing 75 languages. I highly recommend the BTD if done correctly, that is, by doing full genetics analysis as well.

How Does the BTD Work?

Everyone is born with one of 4 blood types: O, A, B, or AB. These letters are blood groups that are categorized based on two antigens, A and B, either being present or absent on the surface of your red blood cells, as well as most of the rest of your body’s cells. For example, someone with both A and B antigens will end up having “AB” blood, but someone with neither antigen present is homozygous recessive which is called “Type O”.

Peter D'Adamo has found that the antigens on your red blood cells that decide whether you’re O, A, B, or AB, are also present in other parts of your body, in fact, most of your other bodily cells including the ones in your digestive tract. Some foods may react with your cells by binding to the different blood type antigens displayed on the surface.

Small side note: Each person also has an Rh factor, which help decide whether you’re positive or negative, as in O+ or A-. There are modifications in the BTD for Rh status, but it’s not as important as your ABO blood type.

How Do I Start the Blood Type Diet?

First you’ll need to find out your blood type, if you don’t already know it. You can request a test from your doctor, or you might be able to get your blood type confirmed while donating blood at a blood drive. Blood type tests taken at your doctor’s or at a blood center are very accurate.

Once you know whether you’re type O, A, B, or AB, you can plan many of your snacks and meals around which foods are better for you, and which ones to avoid. What you’ll eat on this diet depends on your blood type. Here's what D'Adamo suggests for each group:

Type O Diet

Contrary to what some researchers claim, the blood type O diet is not a very high protein diet. It's a medium-protein diet (about 25% protein) that's heavy on lean meats, poultry, fish, fruits, and vegetables, moderate on nuts and seeds, and lighter on grains, beans, alcohol, and dairy. If your goal is to lose weight, you should avoid a lot of carbs and choose more seafood, kelp, red meat, broccoli, spinach, and olive oil. D'Adamo also recommends various supplements to help with various ailments that are common with blood type O, which include inflammation, thyroid issues, gastrointestinal issues, hemorrhoids, diverticulitis, and ulcers. I know a few vegan type Os who try to make it work, but for the most part type Os seem to feel better if they consumed some seafood, if not actual land meats like beef and turkey.

Type A Diet

This involves a more vegetarian diet based on fruits and vegetables, tofu, beans and legumes, and whole grains. However, pundits who claim this is a vegetarian diet obviously have not even read the book, which clearly shows that poultry and seafood are fine for type As. Vegetables, pineapple, olive oil, fish, lentils, and soy are best for weight loss, but dairy, wheat, corn, and kidney beans may lead to inflammation and weight gain.

Type B Diet

Type B is a mix of type O and A in many ways. The diet includes meat, fruit, dairy, seafood, and grains. However, corn, wheat, buckwheat, lentils, tomatoes, peanuts, and sesame seeds should be minimized. Chicken is also very problematic. Green vegetables, eggs, certain meats, fruits, and low-fat dairy are most recommended for Type Bs.

Type AB Diet

Type AB is an enigma, as it did not really exist before 900 AD. Archeologists have not found any remains to date of a blood type AB person, mainly because type B became very common in the Tibet area around 10,000 years ago, so type A and B had not yet mixed. Archeologists call this “admixture.” Type AB individuals should focus on include tofu, seafood, dairy, and green vegetables. D'Adamo says people with type AB blood tend to have reduced stomach acid and enzymes (just like type A), and should avoid caffeine and smoked or cured meats. Some dairy, such as yogurt and kefir, are quite beneficial for type ABs.

BTD: Don’t Believe the Pundits (who are mainly haters)

Many scientists have tried to debunk the BTD, and they are essentially shooting themselves in the foot, while at the same time they are going down a cause-and-effect pathway from which there is no backing up. If your doctor says there’s “no science to back it up”, find another doctor. For those who think the BTD is all about avoiding lectins, think again. There are many lectin-containing foods to be avoided, and quite a few to actually consume more of. What I’ve found is that many of the different aspects of the BTD, along with all its related theories and sub-theories, are quite well-researched. If a food is not recommended, it is either because of lectins, or something completely unrelated to the lectin theory of inflammation and disease.

Any questions, just ask!

Regards,

Val Prisecaru, MS, CN, LDN