Wednesday, April 11, 2007

 

A Plea for Mercy: Correspondence Regarding Juice Plus TGF-β Study

The Juice Plus Research Blog recently received correspondence from someone claiming to be Mercy Dickson, the author of a research abstract that was reviewed by the JPRB on January 21, 2007 in an article entitled TGF-β in Ovarian Cancer: Juice Plus Falls Short of The Real Thing. No information was provided that would allow us to verify their identity so we cannot be certain that the correspondent is actually who they claim to be.

However, if the correspondent is in fact Mercy Dickson, we welcome the opportunity to discuss the research in detail. It brings us no joy to see a potentially promising young investigator inadvertently becoming embroiled in controversy over Juice Plus. Dickson was an undergraduate junior in the Project EXPORT program at Prairie View A&M at the time the abstract was published.[1] The Project EXPORT program is run by the Center for Research on Minority Health at The University of Texas M.D. Anderson Cancer Center. The program’s director, Lovell A. Jones, appeared in a Juice Plus promotional/training video entitled The Science of Juice Plus in 2002[2] and accepted $224,950 in funding from NSA that same year.[3]

The following are excerpts of the correspondent’s letter and our replies to those comments:

Correspondent: “I take research very seriously and I am also disappointed that someone who seems so dedicated to finding truth did not critically assess the published abstract.”
JPRB: It is admirable that the correspondent is passionate about research. However, we did critically analyze the abstract and that analysis is what led us to our conclusions, which we stand behind. If anyone failed to apply sufficient critical reasoning, it was the study’s senior investigators, as detailed below.

Correspondent: “First, there was no mention in the abstract that juice plus was a better diet than the whels diet.”
JPRB: We never said or implied that it did. Please re-read the article.

Correspondent: “the goal of the research was… to investigate the hypothesis of a correlation between high fiber diets and tgf-beta levels.”
JPRB: That may be what young Dickson was told, but it does not appear to be correct. If the true aim of this study was to assess the relationship between dietary fiber and TGF-β levels, then it was profoundly and fundamentally flawed in its design, since there at least 3 confounding factors that were not considered; i.e. fruit/vegetable intake (5 vs. 10 servings), percentage fat intake (10% vs 20%), and use of Juice Plus. A proper design to determine the effects of dietary fiber would have involved comparing two study groups that differed only with respect to fiber intake; however, the 2 groups in this study differed with respect to not only fiber intake but also the amount of fruits and vegetables consumed (which would also translate into differences in nutrient and mineral intake), the percentage of fat in the diet, and the consumption of Juice Plus (which contains very little fiber and unknown or inconsistent amounts of a dozen or so ingredients).

With these confounding variables present, the differences in TGF-β levels between subjects on the Whel and NCI/Juice Plus diets cannot possibly be attributed to differences in fiber intake. Despite what the correspondent claims was the goal of the study, it is apparent to us that the underlying aim of the study was, in all likelihood, to determine whether Juice Plus could provide the benefits of the extra servings of fruits and vegetables in the Whel diet -- and it did not. The study's design is far more consistent with such a purpose than with the one suggested by the correspondent (i.e. detemining the relationship between dietary fiber and TGF-β). We trust that this explanation helps to clarify the justification for our previous comments.

Correspondent: “You seem to make inferences about it being unclear as to whether I sell juice plus and so forth, which is incorrect and contradicts the results and my actual presentation of this data in public”
JPRB: We did not make inferences; we merely stated the truth; it was "unclear” what connections the authors may have had with Juice Plus, and it remains unclear. We further stated that the study was likely funded by NSA and/or connected to Juice Plus hired researcher/spokesperson Lovell A. Jones, which appears to be true and which the correspondent neither confirmed nor denied. When publishing research, the responsibility lies with the investigators to reveal the source of funding and whether or not they have a financial interest in the product under investigation. The correspondent is welcome to forward to us any relevant information that could clarify the financial relationship between the investigators and Juice Plus, but absent such evidence, we are not moved to change our earlier position. However, if this correspondent verifies that they are actually Mercy Dickson and states that they have no financial conflict of interest in Juice Plus, we are willing to add that information in an addendum to the article.

Correspondent: “I also think it is only fair that you either make corrections to your posting or remove it entirely. As I was never contacted, making comments that seem to question my integrity seem unethical. I have worked hard in my academic life and do not appreciate any inferences to me”
JPRB: We are sympathetic and we have no desire to see the reputation of a young researcher jeopardized by association with Juice Plus. However, no compelling reason has yet been presented as to why we should modify the article, let alone remove it entirely. The correspondent did not clarify whether any of the investigators had financial interests or potential conflicts, nor did they reveal the source of funding for the study. Rest assured that if and when additional information is made available, we will share it with the readers of the JPRB, and we do welcome the opportunity for further discussion. Bear in mind also that conducting poorly designed research on a deceptively marketed and controversial product is a career choice for which the investigators ultimately bear responsibility. Our advice to Dickson and other Juice Plus researchers is to exercise great caution when considering researching, accepting funds from, or promoting disreputable products.

We look forward to further communication regarding this research abstract.

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