Original Spin
a sidebar to "Spinning Out of Control"

By Syd Baumel

Justifiably, Robert Cohen criticizes the media for not prying beneath the surface of press releases and news conferences by scientists and vested interests bearing spin. As a would-be example, in "Fooling Most of the People Most of the Time" he reprints Reuters' brief report on the NOWAC breast cancer study. 

But it’s not a very good example. Apart from failing to point out that the milk effect wasn’t statistically significant for adult consumption, Reuters actually did an accurate job. It’s what Reuters left out that's the problem – and I don't mean any of Cohen’s phantom skeletons in the closet. I mean the other research on milk and breast cancer. Any reporter can brush up on it simply by skimming the original paper or asking an expert in the field, including the authors of the study themselves. 

I decided to consult the Internet oracle Google to see how accurately other sources have reported on the NOWAC study. The results were not encouraging for those who value accuracy in public health education.

It certainly was no surprise to find that the U.S. National Dairy Council had celebrated the study with a misleading press release. The Council wrote:

The results of the Norwegian Women and Cancer Study are in line with earlier research results showing the protective effect of milk on breast cancer. A study published in the British Journal of Cancer in 1996 showed that the women who consumed the most milk had less than half the risk of breast cancer compared to women consuming the least milk.  That was all the reference to earlier research the Dairy Council wanted to make. Unlike the NOWAC study’s own authors, the Dairy Council had ignored a similar prospective study, also from Norway, with an entirely opposite finding: women who drank three glasses or more of whole milk per day had nearly three times the incidence of breast cancer compared to women who drank about five ounces or less. (There was also a 70% increased risk for all types of milk combined, but it wasn’t statistically significant.) Nor had the Council mentioned the five other case-control studies that also found a positive association or the nine prospective and case-control studies that found no significant association at all.
Having self-servingly rewritten the history of breast cancer research, the Dairy Council could optimistically conclude that "for now, it appears as if milk may be one part of a well-balanced diet that is a force in the battle against breast cancer."

 

 
 
 

Curious to see what other gems of misinformation the Dairy Council might have on tap, I clicked on their FAQ and soon found the following masterpiece of unintentional irony:

Q. I've recently heard some negative news about milk that contradicts some of the positive news I've heard - how do I know what to believe?
A. Consider the source when evaluating conflicting information. Rely on medical and nutrition information from trained health professionals and reputable organizations, not from animal rights groups or self-proclaimed nutrition experts.
The long arm of the dairy industry, in its Canadian form, evidently had a hand in what should have been an independent report by Canoe, a major Canadian internet news service. After describing the study’s findings with moderate accuracy, Canoe’s reporter cut to another onesided description of the previous research:
Several earlier studies have also noted the protective effect of milk drinking in women, including a Finnish study published in the British Journal of Cancer in 1996. That study, which tracked 4,697 women over 25 years, found that women who consumed the most milk had less than half the risk of breast cancer as women who drank the least amount of milk. 
No other studies are mentioned. Instead, the writer lets just one expert put it all into perspective – the nutritionist-in-chief of the Canadian dairy industry:
For Helen Bishop MacDonald, director of nutrition for the Dairy Farmers of Canada, the study is another solid piece of evidence supporting the idea that Canadian women should be drinking more milk. 

"Women should be doing what Health Canada has recommended for many years – have two to four servings of milk products a day," she said. "This is not encouraging women to have any more than they've already been told they should have." 

Scientists think that the protective factor in milk may be conjugated linoleic acid (CLA) that is found in milk fat. "There have been no end of studies showing in animals that CLA is anti-carcinogenic," said MacDonald. She pointed to a recent study in the journal Anticancer Research showing that CLA from milk fat inhibited the growth of human breast cancer cells. 

 While scientists do have good reason to suspect that calcium and vitamin D – both abundant in milk – have protective effects against some cancers, the case for CLA is compromised by the fact that factory-farmed (grain-fed) dairy cows produce roughly 135 grams of saturated fat for every gram of CLA. The average woman on a 2000 calorie diet would have to drink about five and a half cups of whole milk daily to consume the lowest dose of CLA that helps prevent breast cancer in rodent models of the disease. So far, only one study suggests dietary CLA may play some role in preventing human breast cancer: women with breast cancer were significantly more likely than healthy controls to have very low levels of CLA in their diets and body fat. 

If indeed CLA does help prevent breast cancer in women, no sensible doctor or scientist would recommend boning up on it from dairy foods. The massive increase in saturated fat would aggressively promote heart disease and other adverse health effects. And a growth-promoting hormone in milk (especially from cows fattened with bovine growth hormone, or bGH) called IGF-1 has been implicated as a possible promoter of cancer in humans. Instead, for about a quarter a day, a 1000 mg supplement of CLA (plant-derived) can provide as much as 25 cups of whole milk.

News of the NOWAC study also found its way onto InteliHealth. PC Magazine recently rated this major consumer health site – self-described as "The Trusted Source ®" – as one of the Internet’s top 100 "undiscovered" websites. PC Magazine includes InteliHealth among just 14 other "search and reference" websites in its Top 100. Unfortunately, the uncredited writer of "Drink To Breast Health" (originally published in the The Fort Worth Star-Telegram) also sheepishly follows the pro-dairy flow. The only question he or she raises about the NOWAC study is how milk prevents breast cancer (calcium? vitamin D? CLA?), not if, because none of the other studies are mentioned. This should be cause for concern among Harvard Medical School’s many dairy-doubting scientists (see for example this interview with Walter Willet, director of the Nurses' Health Study), because InteliHealth boasts a medical editorial board which consists of dozens of Harvard doctors and authorities. 
One would normally have high hopes for a report in Science News, reprinted as it is on the website of the Encyclopedia Brittanica. And indeed writer J. Raloff does delve deeper than most into the design of the study and the previous research. Still, he or she only mentions one of the studies (the Norwegian one) that suggested a cancer-promoting effect – and without noting the considerable size of the effect: Another Norwegian study that year had reported that drinking five or more glasses of milk per day [sic: should be three or more] appeared to increase a woman's risk of breast cancer. Confusing the issue, a few other studies around that time showed hints of an anticancer role for milk.  Having created the impression that most studies have found a protective effect, Roloff then allows Robert Heaney, a scientist often funded by the dairy industry who invariably sees the rainbow in every milk bowl, to put (or seem to put, if he was quoted out of context) Hjartaker et al.’s study into misleading perspective: Robert P. Heaney of Creighton University in Omaha, Neb., isn't surprised by the new report. He observes that "there is a modest body of literature supporting this trend." 
One would also have high hopes for a report that bills itself as "a public service of the Office of News and Publications & the Library at UT Southwestern Medical Center at Dallas." Unfortunately, the University of Texas’s "Health Watch" column on "Preventing Breast Cancer" is marred by a scientifically illiterate reading of the literature and a questionable to unacceptable recommendation that women drink more of the white stuff to prevent osteoporosis, heart disease, and possibly breast cancer. On the NOWAC study, the column says:
Drinking milk may be good for your bones, but researchers in Norway say it can also lower breast cancer risk. They found that women who drank a lot of milk during childhood were less likely to develop breast cancer in their 30s. But they also found that women who drank at least three glasses of milk a day as adults had half the risk of breast cancer compared with women who didn't drink milk at all.  In fact, the women were in their mid- to late thirties at the start of the 10-year study and were more likely to have been in their early forties when they developed breast cancer. Another minor point, perhaps, but the "half the risk" effect is an exaggeration: it was a 40% or 44% reduction, depending on how the data were adjusted. But more importantly this reduction wasn’t even close to being statistically significant. Scientists conventionally refer to such results as showing "no difference" or "no significant difference" or (most accurately) "a nonsignificant trend."

Ironically, the column fails to mention the significant effect that was found when childhood and adulthood milk consumption were combined. After citing another study that found a mild protective effect from exercise, the column concludes:

Doctors at UT Southwestern Medical Center at Dallas say there's still no way of guaranteeing that a woman won't develop breast cancer because there are so many factors involved, including genetics and environment. But drinking milk and exercising have so many other health benefits that it certainly won't hurt to do these things. You'll have stronger bones and a lower risk for osteoporosis. You'll also have a stronger heart and a lower risk for heart disease. And, at the same time, you may be protecting yourself from breast cancer. As we’ve seen, there is just as much evidence that milk can increase a woman’s risk for breast cancer. This is ignorant advice. Similarly, research at best justifies recommending low fat milk (or any fruit or vegetable beverage) to help prevent heart disease. The research on milk and osteoporosis is so tepid, it would be a public disservice not to caution women about it lest they get a false sense of security. These are not the kinds of coattails upon which to give milk a free ride in the war against breast cancer.
So did anyone portray the NOWAC study in an accurate light? I stopped looking soon after Google’s hit list passed the point of diminishing returns. But on the way there, I did find one predictably balanced report: the Vegan Society’s briefing paper on "Milk and Breast Cancer" by (who else?) Stephen Walsh. It’s the same clearsighted review that Walsh sent – in draft version – to Robert Cohen in November of 2001, to no avail. 
Syd Baumel is a Canadian writer and the editor of The Aquarian, Winnipeg Vegetarian, and plant-based. A vegan, he serves on the committee of the Winnipeg Vegetarian Association.

See these other sidebars to "Spinning Out of Control":

Encountering Cohen
Bias is as Bias Does

and this appendix:

Syd Baumel’s correspondence with Robert Cohen

For more on the controversy over milk see "Milk: What is the Deal" at www.aquarianonline.com/Wellness/Milk.html

Copyright © 2002 by Syd Baumel.
www.mts.net/~baumel