Came across this Article:

Low-Fat Diet Tops Low Carb In First Controlled Trial

In “gold standard” experiment, subjects lost more weight on the low-carb diet, but more body fat on the low-fat diet.

I love these headlines.  They tell the whole truth without doing any analysis of the information.  They just rush to beat everyone else to the headline.

The Article states in part:

The first controlled trial to pit a low-carb diet against a low-fat diet for weight loss has produced a somewhat split decision. The low-carb approach yielded greater weight loss, but the low-fat path yielded greater loss of body fat, widely considered the more important outcome.

Here are the numbers: The low-carb dieters lost 4.18 pounds, including 8.32 ounces of body fat; the low-fat dieters lost 2.86 pounds, including 13.9 ounces of body fat.

Expressed as percentages, the low-carb eaters lost 46 percent more weight, but the low-fat eaters lost 67 percent more body fat. “Calorie for calorie, reducing dietary fats results in more body fat loss than reducing carbohydrate,” said lead author Kevin Hall, Ph.D., from the National Institutes of Health.

Expressed in those terms, the percentages seem significant.  But wait.  Check out the full Abstract of the “Gold Standard” experiment.  I’ll let you do the reading and draw your own conclusions.  Here are some of my concerns:

  • Each person was on either the Low Fat or the Low Carb Diet with approximately an 800 calorie deficit from their uniform base line diet. Wait – is every person identical?  Do they all weigh the same?
  • At the reduced diet level of approximately 2000 calories:  30% Carbs = 600 Calories/4 = 150 grams of Carbs.  Is 150 grams of Carbs a Low Carb Diet or merely a reduced carb diet?  Shouldn’t the Carb level be below 50 grams?
  • Is the 49% Fat level sufficient?  Shouldn’t it be closer to 65% or more?
  • Is 105 grams of protein – enough?  We do not know anything about the individuals – Nothing.
  • Is 6 days enough to base a conclusion on – or – as we all know – it takes 2-3 weeks to adapt to a true low carb way of eating.

Still the study’s author acknowledges:

Long-term extrapolation of our results is fraught with difficulties.   …. {But then claims} our data suggest that the greater fat imbalance is likely to persist with the LF diet leading to more long-term body fat loss than with the LC diet.

Sorry – this Gold Standard is a bit tarnished.