Blood type diet plan - a critical review

The blood type plan diet was started by Italian naturopath Dr Peter A'damo, whose 1996 book, Eat Right four Your Type, became an international best-seller.

For me, this rings an immediate alarm bell. As explained in my main article on healthy diets, I tend to be suspicious of diet plans formulated by individuals, be they medical or naturopathic doctors.

Many people, however, found the concept appealing. Several friends had asked me to comment on it and I know of one natural health practitioners who quickly got himself certified as a counsellor to give paid consultations on the blood type diet.

One reason for the wide appeal of the blood type diet plan is that it appears scientific, since it requires a blood test before one can proceed further to discover which foods are suitable for his/her blood type.

Yet ironically, the main criticism of this diet is that is is NOT scientific. Read more in Part II of this article on the blood type diet plan.

Condemned?

So how did human beings survive tens of thousands of years before they knew about different blood types?

Even today, billions of people in lesser developed countries still do not know their blood types. According to the theory behind the blood type diet plan, all these people are condemned to poor health. Since there are four main blood groups. each person has a 3 in 4 (75 percent) chance of being sickly from eating the "wrong" foods!

On the one hand, I can accept that technology can be helpful. For example, countries with access to modern medical technology have lower infant mortality rates and longer average lifespans.

On the other hand, I cannot accept that God, the Universe, nature or whatever... would be so cruel and unfair as to penalise large populations on the basis or technology. For basic needs like daily foods, God / nature provides fairly to one and all.

For example, the best food for babies is human breast milk and this is available to all babies regardless of access to technology. We do not need a modern factory to produce infant formula, which remains inferior to human milk. Another example is that tropical foods are most suited to people living in the tropics, while temperate foods are most suited to those living in temperate climates.

Nature provides. Naturally. We need not rely on modern technology for basic foods. And I cannot accept that we need technology to know what we should or should not eat.

An individualised diet?

Another selling point of the blood type diet plan is that it differentiates among people and has different blood type diet food lists for different groups. This is another very attractive idea. Different people have different needs and should eat differently. Makes sense?

To me, if makes more sense that our needs depend not on our blood type, but on factors such as our:

• health condition - whether we are healthy or suffer from degenerative heart disease, diabetes, cancer, etc
• environment - whether we live in the tropics or in cold climates, by the sea or up in the mountains, etc
• lifestyle - whether we are physically active, for example those who do physically demanding work, as well as sportspeople, have different needs compared to those who lead relatively inactive lives.

To me, this makes more sense than saying that people of the same blood type should follow the same blood type diet plan regardless of their health condition, environment and lifestyle.

Issues with meat and milk

Looking at the key recommendations of the blood type diet plan raises further doubts. According to this diet plan...

• Blood type O should eat a low-carbohydrate, high-protein diet with plenty of meat and fish, but little dairy products like milk and cheese.
• Blood Type A should be largely vegetarian, eating plenty of vegetables and fish, avoiding especially red meat, and having a low dairy intake.
• Blood Type B should eat plenty of meat (but avoid chicken and bacon) and dairy, some fish and plenty of fruit and vegetables.
• Blood Type AB should combine the diets of Blood type A and B.

When we look at traditional eating patterns, we see a different picture. Traditionally, until about a hundred years ago, almost the entire world population ate a high-carbohydrate diet with grains as the main food. This pattern of eating continues to be followed today in most parts of Asia, Africa and other lesser developed countries.

Also, the poor in most countries eat very little meat, at most a few times a year during festive occasions, or not at all if they are very poor. In India, about 31 percent of the population - which adds up to more than 400 million people - are vegetarians by practice, regardless of wealth. They are born into vegetarian families and they follow a vegetarian diet from birth till death. Lots more Indians are vegetarian due to poverty.

When we look at the distribution of blood types, we see that Blood Type O is the most common, accounting for about 46 percent of the world's population. Is Dr Peter D'Adamo saying that these people - nearly 3 billion worldwide - would be eating the "wrong" foods if they follow traditional diets or if they are too poor to afford meat?

Another major issue concerns people with Blood Type B (which includes me). According to Dr Peter D'Adamo blood type diet plan spelled out in his book, Eat Right for your Type, these people should eat more dairy foods. Yet large sections of the world's population, including most Asians and Africans, are lactose intolerant and not able to properly digest milk and dairy foods. Are they being "forced" by nature / circumstances to eat the "wrong" foods?

Dr Peter D'Adamo does acknowledge this issue he actually recommends that Blood Type B people who are lactose intolerant should try overcome the problem by slowly incorporating more milk and dairy foods into their diets. To me, this is asking people to change their real-life issues in order to fit his theory, rather than him changing his theory to explain real life situations.

Another problem with milk and dairy foods is that they cause lots of health problems, even among those who are not lactose intolerant. Among other things, high consumption of milk and dairy has been associated with increased incidents of female cancers (breast, ovarian, cervical), diabetes, respiratory problems like asthma, allergies and even osteoporosis - the very problem that dairy foods are supposed to solve. Read more in my article, The Harm of Milk.

These problems associated with milk and dairy foods are believed to be linked with milk processing, especially pasteurisation. Advocates of raw milk claim that milk will not cause these various health problems if it is taken raw. Moreover, the practice of adult humans regularly drinking cow's milk is utterly unnatural. In nature, no adult animals drink milk and no animal drinks the milk of another animal.

Dr Peter D'Adamo does not seem to acknowledge these problems and his blood type diet plan simply asserts that people with Blood Type B should take more milk and dairy products.

Specific foods

Apart from general food (and lifestyle) recommendations, Dr Peter D'Adamo's blood type diet plan also goes into detailed recommendations about specific foods. For example,,,

• Goose and ham are not recommended for all blood type groups. Hmmm... why is goose unsuitable for all? The French fry with goose-fat and the Chinese eat roast goose as a winter delicacy. Are they all getting siok from this? And are all ham bad for health or only the modern commecial types that contain cancer-causing sodium nitrite? What about traditional salt-cured hams like prosciutto or jambon or Chinese Jinhua ham?
  
  
• Lamb is highly recommended for all except Blood Type A, who should avoid lamb.
  
  
• Whole wheat bread is not recommended for Blood types O, A and B, but "neutral" for Blood Type AB. Wow! First time I read that whole wheat bread if bad for most people!
  
  
• Mushrooms and white potatoes are not recommended for Blood types O and A. In addition, Blood type A should also avoid sweet potatoes and yams. In fact, Blood type A have the most "not recommended" vegetables even though they are supposed to follow a largely vegetarian diet.
  
  
• Peanuts are not recommended for Blood types O and B, but recommended for Blood types A and AB. Pistachio nuts are not recommended for Blood types O, A and B but "neutral" for Blood type AB.
  
  
• Ground black pepper is not recommended for all groups, but "pepper, pepper corns" are neutral for Blood types O and B. Errr.... does grinding make all the difference?

And so on.... there are lots of very specific recommendations, which do not seem to follow any theory or philosophy. Dr Peter D'Adamo does not explain how he arrives at these specific recommendations; he seems to be saying "Don't eat these foods because I say so!"

More significantly, his blood type diet plan only makes recommendations on foods that he knows about. If you live in a different country with lots of exotic foods that Dr Peter D'Adamo is not familiar with.. sorry he cannot help you. I bet Dr Peter D'Adamo will be at a total lost if he comes to Southeast Asia!

This, ultimately, is the greatest limiting factor of the Blood type diet plan. It is based on one man's hypothesis and limited to what he knows. Incidentally, Dr Peter D'Adamo's supposed "research" about the blood type diet has not been replicated by other scientists / researchers. The concept is his and his alone.

The blood type diet plan has no system of understanding unlike, for example, macrobiotics which is based on the philosophy of yin and yang. Once you understand this philosophy, you know what to eat and what to avoid, even when you encounter new and unfamiliar foods. You do not need to refer to arbitary blood type diet food lists compiled by one person.

Overall, I find Dr Peter D'Adamo's blood type diet plan arbitary and unacceptable. Yet it is claimed to be based on more than 15 years of "scientific research". Click here to read part II of this article that examines the so-called scientific basis for the blood type diet plan.