Whey Protein and Type O Blood Types

You may enjoy drinking shakes made from protein powder to boost your energy levels. While some diet plans allow moderate consumption of whey protein, the blood type diet claims your whey protein intake should depend on your blood type 5. Peter D'Adamo, a naturopathic physician, developed the Blood Type Diet because he believes certain foods react negatively with your blood proteins 5. The blood type diet is controversial, and most conventional medical professionals do not believe it is a safe or healthy diet plan 5. To determine whether drinking whey protein is appropriate for you, talk to your doctor.

Diet Features

All people have one of four blood types: A, B, AB or O. D'Adamo's Blood Type Diet classifies people by blood type and creates a specific list of foods each type should eat 5. D'Adamo theorizes that the evolutionary origins of a particular blood type determine what foods should be eaten 5. Blood type O was the original blood type in human evolution, developing when early people led a hunter-gatherer lifestyle 5. No scientific evidence suggests that there is an evolutionary link between blood type and diet 5.

Whey Protein

Because early humans with type O blood did not raise animals, the Blood Type Diet asserts they should not eat dairy products 5. Whey protein is a mixture of proteins that remain after milk coagulates. Protein supplement manufacturers commonly use whey protein in products. According to the Blood Type Diet, type O individuals should avoid all whey protein because:

  • it can react with their blood proteins
  • causing digestive
  • health problems 5


Eating whey protein can cause a variety of problems for a type O individual, according to D'Adamo's Blood Type Diet website 25. Proponents of the theory believe protein bars and shakes may cause digestive tract inflammation, leading to bloating. The diet also claims that type O individuals who eat whey protein could experience slowed food metabolism, difficulty producing insulin and altered hormone levels. Over the long term, hormonal imbalance could cause thyroid disorders, water retention and other medical conditions. However, no scientific research confirms these theories.


Mainstream health care professionals reject D'Adamo's theories about whey protein and type O blood 5. Restricting your intake to include a specific list of foods based on your type O blood could cause nutrient deficiencies and other health problems 5. Discuss your concerns about whey protein and type O blood with a physician to determine whether taking whey protein is safe for you.