It's from
Comparison of the Atkins, Zone, Ornish, and LEARN Diets for Change in Weight and Related Risk Factors Among Overweight Premenopausal Women: The A TO Z Weight Loss Study: A Randomized Trial
The lead author does not appear to be a LCer. In general his publications are rather pro plants and quite mainstream. To his credit he has published some negative studies amongst the pro plant stuff. Harvard, ultimately, is no hotbed of pro Atkins zealotry.
If we want to look at the macros we can check here:
A little arithmetic allows us to look at the carbohydrate intake on the first graph at differing time points for Atkins and Zone diets:
Of course the Atkins diet was an unrestricted calories diet, Zone has a caloric restriction applied.
I have the impression from the data of the A-Z study that low carb is good, slightly higher carb is acceptable, adding more carbs back in is a booboo and that the Zone is crap. Just an impression. From the graph.
As an aside, of course the unanswered question is what, exactly, would a sustained 54g carb intake have produced in terms of weight loss over 12 months? Or 20g/d over 12m?
It is very clear that carbohydrate restriction only works WHEN YOU RESTRICT CARBOHYDRATE. A low carb diet does not appear to be as effective as a low carb diet when it has morphed in to an ex low carb diet through added carbs. A similar pattern might apply to ultra low fat diets if anyone wants to go down that dark alley. They don't work when you add fat. Assuming you don't mind the biochemistry while you eliminate fat.
It is also very clear that when comparing an almost-ketogenic diet to a modestly restricted carbohydrate diet of around 133g/d carbs, something like the Zone diet, the modest carbohydrate diet is just as good, if not a little better, than a ketogenic diet. You know the graph:
My problem is trying to square the circle between these two studies. Obviously, no study is free of bias. I struggle somewhat with Dr Sears, of the Zone diet, being the group leader of the study which shows a diet with 133g/d of carbohydrate out performs a ketogenic diet. That is very strange and doesn't happen in Stanford.
People must make up their own minds.
Peter
