A Review of Peter D'Adamo's Eat Right 4 Your Type:The Blood Type Diet
by Declan Twohig
The Rea Centre
A crude synopsis of Peter D'Adamo's Eat Right 4 Your Type: The Blood Type Diet is that our ancestors were all type O blood and ate little else but meat. Later man became clever enough to cultivate crops, and the blood type A evolved with a change in digestive system to accommodate vegetarianism. Then between 10,000 years ago and 1000AD, types B and AB bloods started to appear. And these people have the most tolerant and evolved digestive systems. Dr D'Adamo developed his theory during his studies to be a naturopath, and later developed the theory into dietary suggestions that our foods should match our blood groups based on ancestral eating habits.
The blood type diet theory is based on some pretty weird science which neither Dr D'Adamo nor anybody else has been able to demonstrate as a clinical reality. Eat Right 4 Your Type suggests that the sugars on the surface of our cells which provide the blood group identification tags agglutinate when we eat a group of foods known as lectins. Lectin is used in a purified form for agglutinating cells for blood group testing in laboratories and blood banks. But the same process cannot be demonstrated to happen in the body and would be lethal if it did since almost every food contains some form of lectin. Lectins are digested in the stomach and broken down. They are, anyway, destroyed by the normal stomach acids, and were they not, lectins are destroyed by cooking. Lectins are proteins and when broken down into their constituent parts are no longer capable of functioning as lectins. The food with the highest lectin content is the bean, and this food group is not eaten without soaking and roll boiling, which completely destroys the lectin content.
So, on purely chemical foundations, eating by blood group is essentially totally useless. Its a wacky way of streamlining food intake in the direction of a lower calorie intake, though if you look at some of the blood type diet recommendations the calorie intake for day plans veers all over the place. Additionally, the Eat Right 4 Your Type diet recommended for type O, the commonest group, is not so far removed from the Atkins-style diets, and these are diets high in saturates which are not in the best interests of the cardiovascular system and have links to strokes and some types of cancer. So the nutritional thumbs down says the "blood type" diet is just another fad diet and a bad one at that.
However, if it were that simple, a matter of biochemistry, Dr D'Adamo would be just another guy out to produce a lucrative quick-fix diet best seller, and his book would be tossed aside as boring. But, his work is also offensive because he has the historical ability of a village idiot, and an eye for a great opportunity to bring in a bit of mystical symbolism to cover his lousy scholarship, writing:
"Blood is magical. Blood is mystical. Blood is alchemical....
"The blood of the lamb was placed as a mark on the hovels of the enslaved Jews of Egypt so the Angel of Death would pass them by. Moses is said to have turned the waters of Egypt to blood in his quest to free his people...
"The symbolic blood of Jesus Christ has been for nearly 2 thousand years, central to the most sacred rite of Christianity."
This from Chapter One of a diet book?
D'Adamo writes: "Early life was short, nasty and brutish. People died a thousand different ways -- opportunistic infections, parasites, animal attacks, broken bones, childbirth and they died young."
This is garbage and outdated twaddle.
For a start, D'Adamo confuses the paleo era peoples with Neanderthaler, and it's hard to figure out his time scale. Secondly, it's junk. All the accepted fossil evidence demonstrates that there were accidents where bones were broken, there was death in childbirth, there were mishaps when someone failed to run faster than a tiger. These were not the norm but rather the normal fallout rate of any population.
D'Adamo's statistical ability is lousy too because the early populations were small, and the mishaps would stand out amongst the fossil finds. But the modern analytic technology and methodology demonstrates beyond any shadow of doubt that our early family were superbly healthy and robust compared to today. They had first-rate immune systems so were well-protected against many pathogens, though undoubtedly a bout of malaria would probably not be survived in an era when there was no medical concept.
Their life span wasn't short but certainly there was a range around 50, and the more modern analytic techniques threw up errors in the older calculation methods which can indicate that the early lifespan was close to our own -- and there was no extended period of degenerating health in middle to old age. People remained fit and healthy into old age, and all seemed to die within a relatively close age span -- which indicates two possibilities:
There was a natural "switch off" gene operating in the best interests of a species which could not care for an elderly and dependent population in a hunter gatherer era.
There was a custom similar to that of the Inuit until recently, that there was an accepted age of parting and the old person was left behind as the people moved on. Its been condemned as "murder," but it's a practice you will find in many species living as a group, and it is a voluntary act.
D'Adamo's analysis of the origins of warfare in the Cro-Magnon periods and the wiping out of game populations are countermanded by all the available evidence, and his analysis comes across as fanciful rather than having any sensible and reasoned basis.
In short, D'Adamo's Eat Right 4 Your Type: The Blood Type Diet is not even a good read because it's so full of garbage that it becomes off-putting as a historical account. Neanderthaler was no brute and certainly more than competent within the limitations of his time and lifestyle. He simply lacked enough curiosity to stay the course when the first migrants from Africa arrived on the scene and probably lost out by moving into the forest areas where food supplies caused a population decline into extinction. Nonetheless, Neanderthaler lives on in the genes of many people in Northern Europe.
But it's D'Adamo's matter of blood group evolution that is most touched with poppycock. The molecular evidence for the different ABO groups shows that these blood groups developed maybe earlier than 5 million years ago. An array of blood groups is not any way unique to humans. Gorillas and chimpanzees possess similar.
So, by the time you arrive at homo sapiens -- US! -- there is not a scrap of evidence for the existence of one blood group that evolved later into several, and the new DNA signature testing demonstrates this adequately. Dr D'Adamo is wildly out of date in a decade.
The migration of people out of African happened long before the development of agriculture, and the migrants took their diverse blood groups with them, so there is no evidence that any one belonged to a specifically hunter type. All humans of all blood types were hunter gathers, and hunter gatherers ate a well balanced diet, not a totally meat-based diet as the mighty hunter myths suggest. Agriculture developed more or less simultaneously across the populated world with the exceptions of some group that chose not to adopt agriculture but remained hunter-gatherers
So, D'Adamo's Eat Right 4 Your Type: The Blood Type Diet is bad science, bad history, and tacky nutrition as well.
And it's not even a good read.