Adventures in data searching

A simple inquiry becomes a trip to the twilight zone

Today on a skeptical discussion board there was a post noting a recent 2007 study regarding a possible link between dairy products and Parkinson’s disease. In it, researchers found a possible association between men and women who consume dairy products and an increase in Parkinson’s. This particular study relied on a cohort study ; “The American Cancer Society’s (ACS) Cancer Prevention Study 11 Nutrition Cohort,” that originally was designed to search for population links to cancer.

The studies findings piqued my interest as this is the latest of several publications probing different questions with respect to dairy intake and possible health risks. Many of these studies also pooled from the ACS cohort group while others used different cohorts or data sources.

To date, no broad negative conclusions can be unequivocally made about dairy consumption. Several studies evidence a real benefit in relation to calcium deposition in younger individuals and postmenopausal women. However, there is a 2002 study linking dairy elements (dairy sourced Ca++, lactose, protein, and vitamin D) to Parkinson’s again in men, and another cohort study alludes to a possible association to dairy Ca++ or some other dairy component and increased prostrate cancer risk, and yet another contradicts this one. A variety of inquiries have looked into any possible links to breast, renal, ovarian cancer, and found none. Some relationships to obesity prevention have shown promise, but so far haven’t panned out.

At any rate, it turns out the 2007 study really indicates a possible moderate link, especially in men, who are moderate to extreme dairy consumers and ends with the caveat that further studies are needed. So, looking deeper into an apparent dairy/Parkinson’s link actually produces more questions than answers. This is because cohort studies serve a purpose in that they may provide information that indicates some association between a cause and a disease. The problem here is that discerning a cause and effect link can not be differentiated from just some meaningless correlation.

What ever the case may be, here is where a routine data search began to take a strange turn. During a quick scan searching for biomedical articles through Relemed (a Pubmed related search engine) to get a feel for the existing data on dairy consumption, I noted a 2006 study that stood out. In spite of the fairly innocuous title “ Calcium, dairy products, and bone health in children and young adults: a reevaluation of the evidence.”

The conclusions of the study seemed to contradict a plethora of other studies- not terribly alarming in and of itself: “CONCLUSION: Scant evidence supports nutrition guidelines focused specifically on increasing milk or other dairy product intake for promoting child and adolescent bone mineralization.”

However, looking deeper into the methodology and results, something just did not look right; “A Medline (National Library of Medicine, Bethesda, MD) search was conducted for studies published on the relationship between milk, dairy products, or calcium intake and bone mineralization or fracture risk in children and young adults (1-25 years). This search yielded 58 studies: 22 cross-sectional studies; 13 retrospective studies; 10 longitudinal prospective studies; and 13 randomized, controlled trials. RESULTS: Eleven of the studies did not control for weight, pubertal status, and exercise and were excluded. Ten studies were randomized, controlled trials of supplemental calcium, 9 of which showed modest positive benefits on bone mineralization in children and adolescents. Of the remaining 37 studies of dairy or unsupplemented dietary calcium intake, 27 studies found no relationship between dairy or dietary calcium intake and measures of bone health. In the remaining 9 reports, the effects on bone health are small and 3 were confounded by vitamin D intake from milk fortified with vitamin D.”

For one thing, it appeared there was no consideration for the differing level and weights of evidence based on study type. The study appears in Pediatrics (described as the official journal of the American Academy of Pediatrics) where many unsuspecting practitioners and others might attribute more significance to it than it deserves.

The suspicion that something was not right with the science here led me to look into the studies origin and this is when red flags began to pop up. The studies address describes an organization called the Physicians Committee for Responsible Medicine.

A Google search pulled up a web site describing a typical nonprofit:

“Founded in 1985, the Physicians Committee for Responsible Medicine (PCRM) is a nonprofit organization that promotes preventive medicine, conducts clinical research, and encourages higher standards for ethics and effectiveness in research”

Interestingly, another web site below the official one caught my eye. This site describes the PCRM group as related to an extreme animal activist group:

“The Physicians Committee for Responsible Medicine is a wolf in sheep's clothing. PCRM is a fanatical animal rights group that seeks to remove eggs, milk, meat and seafood from the American diet, and to eliminate the use of animals in scientific research.”

Further inquiry revealed that the The National Council Against Health Fraud (NCAHF) states that “The AMA finds the recommendations of PCRM irresponsible and potentially dangerous to the health and welfare of Americans. The AMA charges that PCRM is "blatantly misleading Americans on a health matter and concealing its true purpose as an animal 'rights' organization.”

So the plot thickens from a seemingly innocent study in Pediatrics Journal to, as one digs deeper, an organization with a vested interest in promoting a dairy health risk agenda. But it gets better!

A perusal of the PCRM advisory board reveals a veritable who’s who of quackery oriented individuals:

• Neal Barnard

"Barnard extols the virtues of strict vegetarian (vegan) diets. He claims that when it comes to life span "It's not genetics or fate that gives people long, healthy lives and cuts other people short; for those who want to take care of themselves, it all comes down to diet."

• Andrew Weil, MD

"As defined by Weil, and by most of the other gurus of alternative medicine, alternative and mainstream medicines are not simply different methods of treating illness. They are basically incompatible views of reality and how the material world works, and they cannot easily be combined into any rational and coherent "integrated" curriculum."

• Henry Heimlich
  

"In Spring 2002, my wife Karen and I began researching the career of my father, Henry J. Heimlich MD, the Cincinnati physician famous for the Heimlich maneuver. To our astonishment, information we compiled from hundreds and eventually thousands of documents revealed an unseen, outrageous career history of medical fraud, a far cry from his public image of medical genius and humanitarian."

Perusing the health section of the PCRM web site, there is an article discussing Parkinson’s disease forwarded by Jeffery Bland PhD and written by David Perlmutter, MD . Dr Bland is perhaps the most notorious peddler of the nutritional supplement support ideology and is deeply involved in psuedoscience. Dr Perlmutters website describes his practice:

“Perlmutter and his staff rely upon a variety of complementary health techniques including vitamin therapy, nutritional supplementation, herbal preparations, massage therapy, EDTA chelation therapy, and others to provide a comprehensive, fully integrated treatment plan specifically designed for the needs of the individual.”

How a person can start a simple data search on dairy consumption and health; end up in the bizarre world of extreme animal activists-and then suddenly find themselves knee deep among peddlers of psuedomedical alternative quackery is utterly mind blowing!

I can almost hear Rod Serling some where in my head… Welcome… to the twilight zone (macabre music in background)……..