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The very person with whom Taubes chose to end his article, Stanford's John Farquhar, was as livid as Reaven. Taubes said that Farquhar had sent Taubes "an e-mail message asking the not-entirely-rhetorical question, 'Can we get the low-fat proponents to apologize?'" On this powerful note, the article ended.
But it's Taubes whom Farquhar wants to apologize. "I was greatly offended by how Gary Taubes tricked us all into coming across as supporters of the Atkins diet," he wrote in an e-mail he broadcast to reporters and to colleagues who were stunned that Farquhar might actually hold the beliefs Taubes attributed to him. "We are against the Atkins Diet," he wrote, speaking for himself and Reaven. "I told him [Taubes] there is the minor degree of merit" to the idea that "people are getting fatter because too much emphasis is being placed on just cutting fats," Farquhar told me. But "once I gave him that opening -- bingo -- he was off and running, even though I said about six times that this is not the cause of the obesity epidemic."
Diets and Data
Taubes proved as adept at clipping data as at clipping quotes. Thus he claimed that one of the "reasons to suggest that the low-fat-is-good-health hypothesis has now effectively failed the test of time" is "that the percentage of fat in the American diet has been decreasing for two decades." (Emphasis added.)
That's true, but irrelevant. The amount of fat consumed has been steadily climbing, as has consumption of all calories. Individual caloric consumption jumped from 3,300 calories per day in 1970�79 to 3,900 in 1997, an 18 percent increase. Per-person consumption of fat grams increased from 149 to 156, a 4.5 percent increase. "We're eating just too darned much of everything," says Farquhar.
Taubes also shoved aside decades of published, controlled, randomized clinical trials comparing nutrient intake and weight loss. His apparent justification in the article was that the "research literature [is] so vast that it's possible to find at least some published research to support virtually any theory." But that's sheer nihilism. Good science is cautious and skeptical, not permanently open-ended. That's why terms like weight of the evidence are used. And the evidence against Atkins-like low-carbohydrate diets is crushing.
In April 2002, for example, the Journal of the American Dietetic Association (JADA) published a review of "all studies identified" that looked at diet nutrient composition and weight loss. It found over 200, with "no studies of the health and nutrition effects of popular diets in the published literature" excluded. In some, subjects were put on "ad libitum" diets, meaning they were allowed to eat as much as they wanted as long as they consumed fat, protein, and carbohydrates in the directed proportions. In others, subjects were put on controlled-calorie diets that also had directed nutrient proportions. The conclusion: Those who ate the least fat carried the least fat.
An alternative method of comparing diets is a meta-analysis, which means not looking at the sum of the whole but actually combining the data. One such meta-analysis, covering 16 ad libitum studies and almost 2,000 people, appeared in the International Journal of Obesity and Related Metabolic Disorders in December 2000. The conclusion: Those on low-fat diets had "a greater reduction in energy intake" and a "greater weight loss than control groups."
"Aren't all these studies highly relevant to the issue of whether an Atkins-like diet works, and don't they indicate that it does not?" I ask Dr. Louis Aronne, director of the Comprehensive Weight Control Program at New York's Weill Cornell Medical Center. "I agree completely," he says. "You're absolutely right."
This wasn't the first time Taubes had published a lengthy article on fat while leaving out this vital information. He also did so in one of his award-winning pieces, a precursor to the "Big Fat Lie" article called "The Soft Science of Dietary Fat" that appeared in Science in March 2001. In a subsequent letter to the journal, three obesity research co-authors, including James Hill, director of the University of Colorado Center for Human Nutrition in Denver, noted, "What Taubes does not mention are the meta-analyses of intervention studies comparing ad libitum intakes of higher fat diets with low-fat diets that clearly show reduced caloric intake and weight loss on the low-fat diet." Taubes responded to the letter but again refused to address these studies.
Why? "They're not worth mentioning," he told me in a telephone interview. They weren't done correctly. None of them? None. The one meta-analysis Taubes thinks was properly conducted appeared in 2002 in The Cochrane Library. Yet it, too, found no advantage to low-carbohydrate diets, merely that "fat-restricted diets are no better than calorie restricted" ones.
Where, I ask Taubes, did all these researchers go wrong? The problem is inherent to an intervention study, he says. "When you counsel people you change their behavior." But doesn't that apply to all the groups in a study? Yes, he grants. "But the idea is to make the intervention effect equal for everyone, whichever diet they happen to be on," he says. "If the interventions aren't the same, then you just don't know how to interpret the results." That may be true, but it's also irrelevant. There's no reason to think persons on either low-fat or high-fat diets got more or less intervention in these myriad studies. Indeed, in some of them virtually all the intervention emphasis was on exercise, with little nutrition counseling one way or the other.
Finally, the comprehensive JADA review published last April also looked at persons who weren't in intervention studies at all but rather were part of the U.S. Department of Agriculture's Continuing Survey of Food Intake by Individuals. An updated report on the survey appeared last June in the Journal of the American College of Nutrition. Both survey reports came to the same conclusion as the intervention studies.
Dr. Aronne is quick to point out that this wealth of data supporting lower-fat diets "is not an endorsement for eating unlimited amounts of nonfat muffins and soda simply because they're fat-free." All carbohydrate sources are not equal. For example, fiber appears to play a powerful role in weight control, but there is no more fiber in a soda than there is in a steak. That said, a high-fat diet does carry an inherent metabolic disadvantage in that fat has nine calories per gram, while carbohydrates and protein each have four.