A common criticism of my work with blood type and diet seeks to brand the BTD theory as a ‘pseudoscience.' Now, according to most accounts, a pseudoscience is ‘any body of knowledge, methodology, or practice that is erroneously regarded as scientific, and which fails to meet the criteria met by science generally.'

According to most accepted sources, a pseudoscience can be identified by a combination of certain characteristics. So, let's see how the BTD measures up:

Asserting claims or theories unconnected to previous experimental results.

It is amply demonstrated in the scientific literature that ABO blood type and secretor status possess biological significance outside of the realm of transfusion science. Roughly 1/3 of all published studies on blood type polymorphism measure some sort of physiologic response, typically having to do with digestion, immunity and circulation.

Asserting claims which cannot be verified or falsified (claims that violate falsifiability).

Falsifiability is the notion that if something cannot be made false, it cannot be proven or disproved. For example, the notion of constructing an anti-cancer diet for type A could be said to be logical based on the fact that virtually 90% of all published studies show a higher rate of malignancy in type A over the other types.

To say otherwise (i.e that type O had a higher occurence over type A) would be to falsify this fact.

Using type A again, we could also say that a cardio-protective diet would be more appropriate in type A, since virtually all published studies show a higher rate of heart and artery disease in type A over the other blood types. Again, to say otherwise would be to falsify this fact.

Not only do we know the occurrence of these facts, we have biomedical reasons for their existence; for example, many types of cancers mimic the type A antigen, and with regard to heart disease, type A has higher levels of cholesterol and more arterial inflammation than the other blood types.

Other studies show that type O have more of a type of inflammation made worse by wheat, whereas non-secretors have lower level of intestinal enzymes that help the body assimilate fats and calcium. Every fact behind the Blood Type Diets neatly falls within the framework of being falsifiable.

Asserting claims which contradict experimentally established results.

No aspect of the characterizations or recommendations of the Blood Type Diets contradict established experimental results. In fact, the inherent flexibility of its doctrine help explain information and results which would otherwise appear aberrant, such as the inability of herd type epidemiology to produce cogent answers to the ongoing debates in nutrition, and the simultaneous persistence of multiple heterodoxies (paleodiet, vegan, etc.)

Failing to provide an experimental possibility of reproducible results.

All aspects of the Blood Type Diets are eminently testable. Ongoing research is monitoring at a variety of recognized biomarkers (soluble endothelial factors, breath hydrogen, to name two) and their modulation as a direct result of adopting a specific blood type diet protocol. Unfortunately, one of the more dire consequences of our internet fueled ability to mudsling to a scale unknown previously is that nascent ideas can easily die stillborn under a barrage of ad hominem and ad hoc attacks, inhibiting serious consideration from independent researchers. This can be especially dangerous to subsequent scholarly analysis; though any scientific theory should be able to withstand the scrutiny of honest research, even if its ultimate goal is to disprove its claims.

Failing to submit results to peer review prior to publicizing them.

I have authored a number of peer-reviewed papers that examined the influence of specific dietary patterns on individuals of differing ABO groups. Predictably enough, they attracted little or no attention at the time of publication. It was only when I wrote a book for the general public, did any of my work attract any sort of attention at all.

By claiming a theory predicts something that it has not been shown to predict.

The characterizations of the digestive strengths and weaknesses of the ABO blood groups and secretor types are a matter of public record; any one with the interest and free time can explore the existing research on MEDLINE or any of the citation services. As I have said time and again, I have merely reassembled and reorganized prior, largely disorganized material into a cogent collection of facts, That as I understand it, is the basis of virtually all scientific development. Paradoxically, if my training as a naturopathic physician was a liability with regard to my ability to develop this theory in a conventionally scientific environment, it was a distinct advantage with regard to the development of a vista broad and flexible enough to knit the disparate facts about blood type, diet and physiology together in the first place.

By a lack of progress toward additional evidence of its claims.

I think the emerging sciences of nutrigenomics and metabolomics will for the first time give the Blood Type Diets the type of intellectual and conceptual framework necessary to allow for their proper place in science to be established. Far from inhibiting or lacking progress towards additional evidence, the Blood Type Diets probably need at least another decade to allow for the genomic discoveries to penetrate traditional medical sensibilities.

This last point illustrates what would be a much more resourceful way to depict the Blood Type Diets: As Protoscience.

Protoscience is a term sometimes used to describe a hypothesis which has not yet been tested adequately by the scientific method, but which is otherwise consistent with existing science or which, where inconsistent, offers reasonable account of the inconsistency. In essence, a Protoscience is an area of science which is in its formulative stages. Some authorities substitute ‘Frontier Science' for Protoscience. I can accept that as well.

In general, pejorative terms like ‘Pseudoscience' are often employed by skeptics and critics, and may often have ulterior motives behind them, such is the politics of science and health care these days.

However, just as we have pseudoscience, let us not forget that we also have ‘pseudoskeptics' as well. A pseudoskeptic is an individual who claims to support "reason" and the "scientific worldview", but frequently uses logical fallacies, attempts to silence opponents, and employs various invalid strategies of persuasion. Funny enough, pseudoskepticism is a class of pseudoscience, masquerading as proper skepticism.

Historically, how many protoscientific discoveries (Galileo's Astronomy and Harvey's discovery of the circulation of blood are two that come to mind) would have at the time of their publication been classed as pseudoscience when in fact they were on the very frontiers of discovery?

Pseudoskeptics have often taken their shots at me and my work. Yet I wonder how some of these folks get away with a skeptical stance about something they appear to know so little about? How often is what we call skepticism is just the simple lack of curiosity?

Now, is this a tome in defense of the inalienable right to be protoscientific?

Hopefully not.

There is a lot of junk out there. Just the other day I received a hostile email from a book reader who chastized me for not 'being honest' about the 'whole secretor thing.' Apparently my lack of honesty in this person's mind centered around my withholding the knowledge that we can change our secretor status with color therapy.

Note: I used quite a bit of material from the Wikipedia for his blog. Paradoxically, Wikipedia features one of the more pseudoskeptic representations on the BTD to be found. But hey, I still love it.