Busting a Gut
Some people will tell you: “I hate to say I told you so”
Not me. I’m thoroughly delighted to say that more than five years ago I told you about a year-long study in which subjects who followed a low-carb diet lost more weight than subjects who followed a low-fat diet.
But here was the detail that I found most striking: Subjects in the low-carb group had a significantly greater increase in HDL cholesterol, and their triglyceride levels also decreased more than those in the low-fat group.
That study was published in the New England Journal of Medicine, May 2003. This past week, NEJM published a similar dietary study with a similar outcome.
And the mainstream nutritional establishment is NOT amused.
Can money reduce weight?
On the morning the new study was released I watched the Today show and happened to catch an interview with NBC News Chief Medical Editor Dr. Nancy Snyderman who was nearly seething over the NEJM study.
The study compared three diets – a low-fat diet, a low-carb diet, and a Mediterranean diet. More than 320 moderately obese subjects with an average age of 52 followed these diets for two years. Results showed that subjects in the low-carb diet group lost the most weight. In addition, the ratio of total cholesterol to HDL was reduced by 20 percent in the low-carb group, but that reduction was just 12 percent in the low-fat group.
After admitting that the low-carb diet prompted greater weight loss, Dr. Snyderman says that the “only problem” with the study is that it was funded by the Atkins Foundation.
Hmmm. I wonder how that Atkins money prompted weight loss and improved cholesterol ratios (unless she’s subtly accusing researchers of falsifying results). I also wonder if, in the future, she’ll be dismissive of clinical trials funded by drug companies.
Are you holding your breath? Me neither.
End of the day
Dr. Snyderman insists that the study was “very flawed,” based on two factors: 1) “The low-fat diet didn’t lower the fat much at all,” and 2) “the conclusion they came to is that you can eat more calories with an Atkins-like diet and lose weight”
Reality time: 1) The low-fat diet followed low-fat guidelines set by the American Heart Association: 30 percent of calories from fat, 10 percent of calories from saturated fat.
Reality time: 2) Researchers didn’t conclude that you can eat more calories with the low-carb diet – they actually TESTED that. Unlike the other two diets, the intake of total calories, protein, and fat were not limited on the low-carb diet (although subjects were counseled to “choose vegetarian sources of fat and protein and to avoid trans fat”). Nowhere in the study’s conclusions do the authors state that you can eat more calories with an Atkins-like diet and lose weight.
Ignoring those annoying details, Dr. Snyderman warms up for a dramatic slammer: “Here’s the fatal flaw in that reasoning. There is one equation at the end of the day that allows you to lose weight: It’s calories in, calories out. It’s just like your checkbook. So you can’t eat more calories on one kind of diet and then lose more weight.”
And yet, that appears to be exactly what happened among low-carb subjects in this study.
Watch out for that bus
Toward the end of the interview, Dr. Snyderman shows her true colors by noting that she discussed this study with Dr. Dean Ornish, who she fondly describes as “the low-fat diet guru.” She’s got that right. Dr. Ornish recommends fat intake well below the AHA’s 30 percent.
And then – to complete her evisceration of the NEJM study – Dr. Snyderman offers this bon mot: “I think it’s a great example of the fact that a leading medical journal can have a leading article and it doesn’t necessarily mean that it’s gospel.”
Whoa! A medical mainstream doctor on a mainstream morning show throwing one of the leading mainstream medical journals under the bus! I love it!
I wonder how Dr. Snyderman must have reacted to this conclusion from a 2007 study that appeared in the Journal of the American Medical Association: “In this study, premenopausal overweight and obese women assigned to follow the Atkins diet, which had the lowest carbohydrate intake, lost more weight and experienced more favorable overall metabolic effects at 12 months than women assigned to follow the Zone, Ornish, or LEARN diets.”
Ouch! That’s going to leave a mark.
Sources:
“Weight Loss with a Low-Carbohydrate, Mediterranean, or Low-Fat Diet” New England Journal of Medicine, Vol. 359, No. 3, 7/17/08, content.nejm.org
“Vide Cut carbs, not fat, study says” NBC Today show, 7/17/08, today.msnbc.msn.com
“Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in weight and Related Risk Factors Among Overweight Premenopausal Women” Journal of the American Medical Association, Vol. 297, No. 9, 3/7/07, jama.ama-assn.org