Gary Taubes hypothesis in the Case Against Sugar is simple and straightforward:
Sugar is toxic and the primary cause of diabetes and obesity.
He readily acknowledges that scientific research in the area of nutrition is complex and does not easily result in clear-cut answers. As a result he believes that such a hypothesis can neither be proved nor disproved. He does accuse nutrition research, however, of being stuck in the past and unable to grasp the dangers of fructose-containing sugars. The book states his hypothesis, provides a history of sugar research and points to a new direction for studies on sugar and health.
Although I have grave reservations about the book as a whole, there were some interesting points made that I understand to be factual and are generally ignored by critics of processed food. In chapter Nine, “What They Didn’t Know,” he presents one of the best explanations I have read as to why it is so difficult to get definitive answers to popular questions when conducting research in human nutrition. In his discussion on the relationship between hypertension and sodium, he notes that not everybody is sensitive to sodium. In his case against Big Sugar, he points out that it was research sponsored by the sugar industry that cast suspicion on artificial sweeteners. Although I have seen the term “Western Diet” used widely, I did not realize that its source was the book Western Diseases1 by Trowell and Burkitt that is the origin of the term.
In his rather scatter-shot writing style, Taubes goes into depth in certain areas of the history of sugar research while leaving out some critical details. I thought the overview of more than a 100 years of research on sugar was highly selective appearing to endorse studies which support his hypothesis and relegate those which do not as examples of “Bad Science.” I fail to see how he could devote so many pages to the evolution of knowledge about insulin and diabetes without mentioning the scientists Banting and Best. In condemning all fructose-containing sugars including sucrose, it seems strange that he exonerates fruit sugar which also contains fructose and sucrose in similar proportions. He condemns nutritionists for buying into the “lipid hypothesis” when they should have realized that it was really sugar that was the problem all along. From my perspective the lipid hypothesis was much more pronounced in popular nutrition articles and books over the past fifty years than in the scientific literature. Taubes seems to be leading the charge to make sugar the new fat.
I find many statements and conclusions to be disturbing. Like many authors of pop-nutrition, the author discounts the importance of calories in the development of diabetes and obesity. Taubes argues that the obsession of nutritionists with calories obscures the toxic nature of sugar. I wish that he would have delved into the more recent research on the topic rather than get hung up on studies conducted over the last century when far fewer tools were available to researchers. When the author describes that research, however, his desire to demonstrate the dangers of sugar leads to naming sugar as the cause of cancer, dementia, hypertension (he rejects the salt hypothesis), and gout in addition to diabetes and obesity. According to this line of reasoning, sugar is the most toxic component of the Western Diet. He relies on Occam’s razor which suggests that the simplest explanation is the most likely solution to a problem while ignoring Einstein’s warning to keep it as simple as possible but no simpler. Have we become a society that is incapable of dealing with complexity?
I do not begrudge the author of this book his skepticism. Skepticism is an important ingredient in research. Scientists must be skeptical of ideas both those of others and their own. It would appear, however, that Taubes has fallen in love with his own hypothesis and fails to produce a convincing case. Yes, observational studies link sugar and insulin resistance to many diseases and disorders, but correlation does not prove causation. In science, particularly medical biochemistry, a plausible mechanism must be advanced and tested. Had the author spent more effort on explaining how various studies from disparate fields link sugar to a critical role in disease development, I would have taken his claim of its toxicity more seriously. Had he shown how excess consumption of sugar contributes to the development of diabetes and obesity in conjunction with its contribution to calories in foods, particularly those low in other nutrients, I would have been more sympathetic to his argument. Unfortunately, he chose to spend too much of his prosecutorial energy on bashing Big Sugar and medical research on nutrition. I find the case that Prosecutor Taubes makes to be inadequate. While sugar is certainly not blameless, the author has not provided sufficient credible evidence to support a conviction on the charges levied.
Next week: My personal journey with sugar
1 Trowell, H.C. and D.P. Burkitt, 1981. Western Diseases: Their Emergence and Prevention Cambridge, MA: Harvard University Press.