Let’s Talk about Weight Loss with the Blood Type Diet

Hey Angels and Alphas,

In the world of weight loss, individualized nutrition has become very, very important when it comes to creating lasting health changes. That is, assessing an individual, as well as getting to know their bodies and developing goals and behavioral changes that are based on their individual lifestyles and medical history. 

Generalized recommendations simply tend to not work that well (case in point, diets.) Not only that, but many people would prefer a plan that’s tailored to them. 

That’s why the appeal surrounding the “blood type diet” can be somewhat understood. However, even though this way of eating is making shockwaves throughout the weight loss industry, the science behind its effectiveness seems to be scarce. 

Let’s get into the details of the blood type diet and see if it’s a worthwhile option for you to try.


The blood type diet happens to be developed and mostly promoted by a naturopath back in the ‘90s, who wrote a very popular book on the topic. 

He claimed that everyone should follow specific dietary patterns based on their specific blood type (A, B, AB and O), and the main reason for this is both genetic as well as linked back to the diets that our ancestors used to consume and thrive off of. 

Each blood type is basically given a name associated with a type of ancestor (i.e., the “hunter” or “nomad”) along with a list of food guidelines. 

One group should avoid red meat, another should avoid wheat but can eat red meat, and another can’t have kidney beans and chicken, while the last one can’t have grains or legumes but can thrive off a diet that is high in protein. 

In general, these diets range from vegetarian to a more Paleo-type diet. 

To take this even further, theories about this diet are also based on the potential effects of proteins found largely in raw legumes called lectins, which may interact negatively with the gut and cause the clumping of red blood cells in certain blood types. Of course, the main promise is better overall health (and often great weight loss results) if you follow the diet associated with your blood type.


Let’s be frank – there is none. There was even a review back in 2013 of the available articles and studies on the topic, finding pretty much no evidence of health benefits from the blood type diet. 

Not one single study has supported the claims that this diet makes, which just goes to show anyone can write a popular book or talk about a diet or nutrition and not have the evidence to back up their claims. 

Moreover, it has to be said that if a diet or nutrition theory is super popular and promoted by your favorite social media influencer, this does not mean it’s legit or that it has any science behind it. The theory about lectins can be easily squashed as well because lectins in raw legumes are simply destroyed when they are cooked.


To be honest, some of the concepts behind the “blood type diet” aren’t all bad because they involve consuming more plants and fewer processed foods. 

And following these principles will, without a doubt, help your health goals. 

That being said, general good nutrition advice often involves eating more plants and less processed food too, and this is in no way tied to your blood type. The real task is how you can actually incorporate these general improvements in nutrition in a way that fits into your specific life. 

For example:

  • Not skipping meals
  • Cooking at home 3-4 nights of the week
  • Adding green veggies to your lunch
  • Adding a protein source to your breakfast 
  • Snacking on fruits or nuts

These are all common goals all of us should work on, but they can even be further individualized based on lifestyle and goals. That is how positive and long-lasting healthy behavior changes happen.

The bottom line is, there is zero science that diets tailored to specific blood types work. However, the concept of individualized nutrition recommendations is definitely the right path for the field of nutrition and dietetics.