It is surely no secret that the United States, and, increasingly, the rest of the world, is wallowing in an epidemic of diabetes (the CDC says that one of every four American teenagers has type 2 diabetes, with the expectation that by 2040, it will one in three.Teenagers!), and that many doctors and other healthcare providers consider sugar to be at least one culprit. It is therefore somewhat surprising that Gary Taubes, in his latest book, The Case Against Sugar(Knopf: 2016), takes the position that there is a serious debate, if not a war, raging about this, and that he must therefore prosecute sugar as responsible for just about every major ill we have, including cancer and Alzheimer’s. For my purposes, though, I’d just like to see agreement that sugar is clearly responsible for a few: diabetes, metabolic syndrome, heart disease, and hypertension (high blood pressure). That’s because I have been diagnosed late in life with two of those at least: type 2 diabetes, and high blood pressure. I have both more or less under control, but anything that can bring clarity to what causes either or both is welcome.
For Taubes, the case is crystal clear. The culprit is sugar, especially the refined sugar called sucrose (half glucose, half fructose) andthe ingredient that seems to be in just about every prepared food one buys these days, high-fructose corn syrup(55% fructose, 45% glucose). These are the empty calories that Americans and inhabitants of all advanced industrial countries have been consuming in ever greater amounts for a few hundred years (Americans in 1999 were consuming an average of 158 pounds of sugar per year). And according to several studies that Taubes cites, it is this major dietary change that accounts for the damage wrought to our bodies. Humans have simply not had time to evolve fast enough for our bodies and organs (particularly the liver and pancreas) to handle the huge increase in refined sugars we now consume. This evolutionary argument is one of the best Taubes makes. For example, he notes that yearly per capita consumption of sugar “more than quadrupled in England in the eighteenth century, from four pounds to eighteen pounds, and then more than quadrupled again in the nineteenth,” while in the United States “sugar consumption increased sixteen-fold over that same century” (42). But the real argument comes in studies done more recently on indigenous populations like American Indians and Africans who have changed to Western-style living more recently and more rapidly. Among the Indians of Arizona, for example, the Pima, along with other Native Americans, have seen diabetes rates explode from almost nothing when eating their native diet to over 50% and more now, after changing to a Western diet laced with sugar and immense quantities of soda. Another major study, Western Diseases(1981) by Denis Burkitt and Hugh Trowell on indigenous populations in Africa, saw tooth decay, gout, obesity, diabetes, and hypertension skyrocket with Westernization (229). Another study of natives from Tokenau, an island near New Zealand, saw the same phenomenon: from a diet of coconut, fish, pork, chicken, and breadfruit (a high-fat diet, Taubes notes), the Tokenau people shifted to western ways in the 1970s. Some migrated to the big island of New Zealand, while some simply stayed on Tokenau, but both adopted western ways and foods. Diabetes shot up to engulf almost 20% of the women and 11% of the men, with corresponding increases in hypertension, heart disease, and obesity. To sum up, Taubes quotes one of his heroes, John Yudkin, a University of London nutritionist, who wrote in 1963: “We now eat in two weeks the amount of sugar our ancestors of two-hundred years ago ate in a whole year” (154).
But many of us have heard these stories and statistics before. What is surprising and even shocking in Taubes’s arguments are the supportive and historical facts. As one might guess from his argumentative title, not everyone agrees with Taubes. In fact, for the major arbiters of American eating policy like the FDA and the NIH (National Institutes of Health), sugar has remained a kind of untouchable, on the list of GRAS (generally recognized as safe) foods until virtually the present day (a quick Google search revealed that the latest FDA recommendations concerning sugar only warn that sugar can cause tooth decay!). This contrasts with FDA decisions on the sugar substitutes saccharin and cyclamates, which, with urging from scientists sponsored by the sugar industry, have been listed as possibly carcinogenic. But the major thrust of the scientists like Ancel Keys of the University of Minnesota and Fred Stare of Harvard (both funded handsomely by the sugar industry, Taubes points out) has been twofold: first, that it is the fats in our diets that kill us prematurely in the West, via heart disease and diabetes; and second, that “we get obese or overweight because we take in more calories than we expend or excrete” (107-9). Taubes calls this “the gift that keeps on giving,” because it essentially exonerates sugar from any role in obesity or diabetes or the host of other diseases plaguing Western societies. It doesn’t make any difference what you eat, goes this mantra, because “a calorie is a calorie.” Eat too much food (too many calories), and exercise too little, and you get fat, which causes you to get diabetes and die early. Period. End of discussion. Forget about the impact of refined foods (white flour, white sugar) on one’s metabolism.
Taubes goes into most of the studies and white papers that chart this, to him, massive fraud, but it’s not necessary to repeat that here. Suffice it to say that the sugar industry has used its massive profits and political clout to pretty much cloud the issue of sugar’s deadly effects in much the same way the tobacco industry clouded, for years, the dangers of tobacco smoke. Indeed, one of the really surprising roles of the sugar devil is in flavoring tobacco. Yes, that’s right. Tobacco growers and cigarette makers learned around the turn of the twentieth century that tobacco in cigars and pipes wasn’t really selling enough product (getting enough people hooked). So, in 1914, R.J. Reynolds introduced Camels, “the first brand of cigarettes made of multiple tobacco types (basically flue-cured Virginia, and Burley tobacco) blended together” (64). Sugar entered in two ways. First, flue-curing the Virginia tobacco turned a natural sugar content of about 3% to one of 22% sugar. That higher sugar content makes the tobacco more inhalable, because the smoke becomes acidic, not alkaline (alkaline smoke irritates the mucous membranes and stimulates coughing, which is why pipe smokers rarely inhale). Second, the nicotine-rich Burley tobacco was “sauced” with sugars from honey, molasses, licorice and so on. This was first done for chewing tobacco, but Reynolds put it in Camels, and this really did the trick. Why? Because by blending “sauced” Burley tobacco with already-sweetened flue-cured Virginia, Camels were able to deliver a sweet-tasting and -smelling cigarette that was easier to inhale, and thus “maximized the delivery of nicotine—and carcinogens—to the human lungs” (69). Most other tobacco companies and brands wasted no time following Camels to the point that “by 1929, U.S. tobacco growers were saucing Burley tobacco with 50 million pounds of sugar a year” (69). That this is not fiction is evidenced by Taubes’s quoting of a 2006 report from the Netherlands: “Consumer acceptance of cigarette mainstream smoke [what’s directly inhaled] is proportional to the sugar level of the tobacco” (70). In other words, sugar’s key role in making cigarettes palatable (inhalable) to both men and women worldwide contributed in a major way to the epidemic of lung cancers that are still with us.
Taubes has endless data on the role of sugar in diseases, but a couple stand out. First, he cites studies showing that sugar may well be addictive (as anyone with children knows). It elicits a response in the brain’s “reward center,” e.g. the nucleus accumbens, that closely resembles the response from nicotine, cocaine, heroin, and alcohol. This may help explain why its rise has been so spectacular in every society where it was introduced. More important, to me at least, is the connection Taubes tries to make between sugar and what is now generally conceded to be a key factor in diabetes and a host of other diseases that cluster with it—insulin resistance. Insulin, of course, is the hormone produced in the pancreas that acts to combat high blood sugar. Basically, when blood sugar (glucose) levels rise, the pancreas responds by secreting insulin, which “signals the muscle cells to take up and burn more glucose.” Insulin also induces cells to store some of the glucose as fat (insulin is said to be “lipogenic” or fat-forming). Then, when blood glucose falls, the insulin level falls too, and the stored fat can be burned instead of glucose. The problem is that some people (and increasing numbers in Western societies) exhibit a condition known as “insulin resistance”: their cells do not accept the insulin, and hence the glucose levels in the blood, and the levels of insulin, remain high or get higher.
The question is: what causes insulin resistance in the first place?
This would appear to be the 64-million-dollar question (the fight over this is quite active even today, with one side blaming the “drop in insulin sensitivity” on a fat, “intramyocellular lipid” said to block cell receptors from accepting insulin; and another blaming insulin resistance on excess carbohydrate [especially sugar] consumption and too much insulin production). Oddly, Taubes himself does not give a conclusive answer. He strongly suggests that insulin resistance is caused by too much sugar consumption, but he hedges. He says that in contrast to the sugar industry’s old mantra that insulin resistance and diabetes are caused by obesity, i.e. eating too much or consuming too many calories, another possibility
is that these elevated levels of insulin and the insulin resistance itself were caused by the carbohydrate content of our diets, and perhaps sugar in particular. Insulin is secreted in response to rising blood sugar, and rising blood sugar is a response to a carbohydrate-rich meal. That somehow this system could be dysregulated such that too much insulin was being secreted and that this was causing excessive lipogenesis—fat formation—was a simple hypothesis to explain a simple observation. (120-1).
But because insulin resistance is so important as a causal factor in diabetes, obesity, metabolic syndrome, heart disease, and so on, we would like something firmer. Taubes doesn’t give it to us, partly, he explains, because the NIH decided long ago not to fund long-term studies on the effects of sugar in the American diet because it would cost too much. It would also take a long time, since diabetes does not manifest overnight; like tobacco, sugar’s effects usually take years to manifest. But still, we want more. And Taubes does cite one study from Switzerland that seems to provide some scientific proof. Luc Tappy of the University of Lausanne studied fructose (fructose is metabolized without the need of insulin) in the mid-1980s. What his study found is crucial, even though it was short-term:
When Tappy fed his human subjects the equivalent of the fructose in 8 to 10 cans of Coke or Pepsi a day—a “pretty high dose” as he says—their livers would start to become insulin-resistant and their triglycerides would elevate in just a few days. With lower doses, the same effects would appear but only if the experiment ran for a month or more (205).
This would seem to be a sound study, indicating insulin resistance and elevated triglycerides, both key markers for diabetes and for heart disease, from excess sugar. But again, its effects derived only from the use of fructose—though that is the main ingredient in most sugared drinks and lots more, via that demon invention, high-fructose corn syrup.
Unfortunately, this is as much as Taubes provides concerning insulin resistance. And that is a shame.
Still, Taubes’s book is well worth reading, if only for the disgraceful history it unfolds, a history of sugar that has scarred this nation from its very beginnings (slavery and sugar are intimately intertwined) and which still, in 2018, thanks to the power of the sugar industry in shielding its product from blame, continues its devilish work.
Lawrence DiStasi
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