One of the more startling results of the A to Z Weight Loss Study is the interpretation of the results. Again, the study found that after 12 months, those participants on the Atkins diet lost more weight and ended with a metabolic (cardiovascular disease) profile no worse than those on the comparison diets thought to be “healthy” diets. Those participants in the Atkins diet arm of the study on average consumed significantly more saturated fat, more protein and less dietary fiber than the other diets (Table 2 of the study in question[1]). They in essence ate large amounts of foods that might be considered unhealthy by most current nutritional standards. And after a year (granted that’s a fraction of the time needed to prove it a safe and healthy diet) the participants lost the most weight and didn’t suffer with metabolic indices indicative of unhealthy eating.
One critical aspect of this study to keep in mind is the brief glimpse it gives. Dietary lifestyles take many times ten to twenty years of exposure to impact for example the cardiovascular system. While indices of cardiovascular risk are within the range of other “healthy” diets, the indices measured may not tell the entire story. As a case in point, the genesis of atherosclerosis is thought to be due to trapped Low Density Lipoproteins (LDL) stuck in the arterial walls, consumed by tissue macrophages which expire in the arterial wall leaving thick goo. The goo expands into the arterial lumen and the nidus of a plaque is created. With that genesis in mind, might the Atkin's diets impact the oxidizability of LDL, leaving the absolute amount of LDL unchanged?
Another important consideration: The study was conducted in women. Is the result generalizable to both women and men? Or is another study with the same methodology needed for men? And what if the results were different, what could we conclude? The answer from my perspective is: it depends on the winds of nutritional change. Trans fats were never found to be unhealthy (lead to adverse cardiovascular indices) in men yet the unsavory results of the Nurses Health Study were generalized to men (never mind the results of the Physicians Health Study, which found no adverse metabolic effects of trans fats in men). But that’s another soap box.
What do the authors of the study conclude? I’ll quote one the study authors ending remarks:
“Physicians whose patients initiate a low-carbohydrate diet can be reassured that weight loss is likely to be at least as large as for any other dietary pattern and that the lipid effects are unlikely to be of immediate concern.”
So there you have it. The whole nutrition cycle begins to churn again. Fat is good for you, carbohydrates are evil and the Atkins diet we all shunned for so many years because of the perceived adverse effects of eating bacon, pork and fatty foods, is shown to be as healthy as all the other dietary approaches. As Daniel Boornstein was quoted as saying,
One critical aspect of this study to keep in mind is the brief glimpse it gives. Dietary lifestyles take many times ten to twenty years of exposure to impact for example the cardiovascular system. While indices of cardiovascular risk are within the range of other “healthy” diets, the indices measured may not tell the entire story. As a case in point, the genesis of atherosclerosis is thought to be due to trapped Low Density Lipoproteins (LDL) stuck in the arterial walls, consumed by tissue macrophages which expire in the arterial wall leaving thick goo. The goo expands into the arterial lumen and the nidus of a plaque is created. With that genesis in mind, might the Atkin's diets impact the oxidizability of LDL, leaving the absolute amount of LDL unchanged?
Another important consideration: The study was conducted in women. Is the result generalizable to both women and men? Or is another study with the same methodology needed for men? And what if the results were different, what could we conclude? The answer from my perspective is: it depends on the winds of nutritional change. Trans fats were never found to be unhealthy (lead to adverse cardiovascular indices) in men yet the unsavory results of the Nurses Health Study were generalized to men (never mind the results of the Physicians Health Study, which found no adverse metabolic effects of trans fats in men). But that’s another soap box.
What do the authors of the study conclude? I’ll quote one the study authors ending remarks:
“Physicians whose patients initiate a low-carbohydrate diet can be reassured that weight loss is likely to be at least as large as for any other dietary pattern and that the lipid effects are unlikely to be of immediate concern.”
So there you have it. The whole nutrition cycle begins to churn again. Fat is good for you, carbohydrates are evil and the Atkins diet we all shunned for so many years because of the perceived adverse effects of eating bacon, pork and fatty foods, is shown to be as healthy as all the other dietary approaches. As Daniel Boornstein was quoted as saying,
“The greatest obstacle to discovery is not ignorance—it is the illusion of knowledge.”
[1] Christopher D. Gardner et al. 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 JAMA. 2007;297:969-977.
[1] Christopher D. Gardner et al. 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 JAMA. 2007;297:969-977.
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