We’ve been fighting this notion that “a calorie is a calorie is a calorie” for some time now, but it looks like the establishment may be finally understanding the implications of its own research.  In a new study published in the Journal of the American Medical Association, the authors discover that when calories are consistent across people, the group on a high fat, low carb diet burned 300 more calories per day and had a significantly higher resting energy expenditure (REE):

The decrease in REE from pre–weight-loss levels, measured by indirect calorimetry in the fasting state, was greatest for the low-fat diet (mean relative to baseline [95% CI], –205 [–265 to –144] kcal/d), intermediate with the low–glycemic index diet (–166 [–227 to –106] kcal/d), and least for the very low-carb diet (−138 [–198 to –77] kcal/d; overall P = .03; P for trend by glycemic load = .009).

So, if you’re just sitting on your butt watching reruns of Futurama, you’re burning more calories on a low carb diet than you would be if you were on a low fat diet.

The study also notes the differences between leptin, cortisol and C-Reactive Protein levels amongst those on the various diets (low carb had lowest levels of leptin and higher levels of cortisol and C-RP during this study. This is why you take your fish oil.).

There’s a whole bunch of other fascinating correlations between diets and various health markers. Not all are in favor of low carb, but all are worth reading and understanding.

Most inspiring for me is this statement further down in the study:

The results of our study challenge the notion that a calorie is a calorie from a metabolic perspective.

Different foods have different effects on your body. People always seem ready to make this assumption when it supports eating a low fat diet for weight loss, but now the evidence suggests that a low carb diet actually is of far greater benefit for those looking to lose weight.

Other interesting quotes unashamedly taken out of context:

  • The low-fat diet produced changes in energy expenditure and serum leptin42 – 44 that would predict weight regain. In addition, this conventionally recommended diet had unfavorable effects on most of the metabolic syndrome components studied herein.
  • The very low-carbohydrate diet had the most beneficial effects on energy expenditure and several metabolic syndrome components, but this restrictive regimen may increase cortisol excretion and CRP.

 

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