Thursday, 15 September 2016

Glantz's sugar conspiracy

Stanton Glantz seems to have decided that he can recreate the Big Tobacco revelations of the 1990s with Big Sugar in the 2010s. You can't repeat the past? Why of course you can! His latest effort was published in JAMA Internal Medicine and led to headlines like this...

These headlines are a significant over-reaction to a mildly interesting story about a fairly obscure evidence review published fifty years ago. There seems to have been a lack of transparency in the study's funding, but I have been unable to ascertain whether the study's findings were correct or not. Glantz's study does mentions this salient fact, however...

Although the contribution of dietary sugars to CHD is still debated, what is clear is that the sugar industry, led by the Sugar Association, the sucrose industry’s Washington, DC–based trade association, steadfastly denies that there is a relationship between added sugar consumption and CVD risk.

So we are dealing with a scientific debate that is unresolved even today. And the narrative of industry-funded corruption doesn't look very strong if Walter Willett is to be believed...

Dr. Walter Willett, who knew Hegsted and now runs the nutrition department at Harvard’s public health school, defended him as a principled scientist.

“He was a very hard nosed, data driven person, who had a record for standing up to industry interests,” including losing a job at the USDA for standing up to the beef industry, Willett wrote in an email. “I very much doubt that he changed what he believed or would conclude based on industry funding.”

Willett said today, research has become more clear, showing that refined carbohydrates and especially sugar-sweetened beverages “are risk factors for cardiovascular disease,” while “the type of dietary fat is also very important.” But he said that at the time Hegsted and colleagues were writing, evidence for fat as a risk factor for coronary heart disease was “considerably stronger” than for sugar, and he would agree with “most of the interpretations” the researchers made.

“However, by taking industry funding for the review, and having regular communications during the review with the sugar industry,” Willett acknowledged, it “put him [Hegsted] in a position where his conclusions could be questioned.”

“It is also possible that these relationships could induce some subtle bias, even if unconscious,” he added.

Possible unconscious bias doesn't quite sound like being 'bribed by Big Sugar to demonise fat' to me, but I get the impression that the veracity of his research isn't of interest of Glantz, who also prefers to play the man rather than the ball. In his mind, the vexed question of whether sugar independently causes heart disease is answered by the fact that a nutritional scientist didn't disclose a conflict of interest to the NEJM decades ago when the NEJM didn't require conflict of interest statements. The fact that the meat industry, egg industry, olive oil industry and many other parts of the food sector fund scientific research seems to have passed him by.

If I understand Glantz's hypothesis correctly, he seems to think that selectively quoting some 1960s correspondence proves that the sugar industry created the scientific consensus on saturated fat. This is such an outlandish conspiracy theory that only Glantz could attempt it. Up until now, Ancel Keys has been the anti-sugar fanatics' chief villain. Will we gradually see him written out of history to make way for a classic Big Industry morality play?

I only mention all of this to point you in the direction of an excellent blog post by somebody who knows much more about this subject than I do. It seems that Glantz's study is seriously lacking in context and is ignorant of the science. What a surprise that is.

Do read it.

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