The Study to end the Low Carb Vs Low Fat Debate – Maybe
Last week, August 13, 2015, in the journal Cell Metabolism, a study was published that demonstrated that a fat restricted diet had more fat loss than a carb restricted diet. But before you go out to buy the Spaghetti and Garlic Bread that you’ve been depriving yourself of all these years, you need to know a few more details.
Nineteen, yes just 19, obese subjects were very tightly controlled into either a fat restricted vs a carbohydrate restricted diet for 6 whole days (that is read sarcastically as Six. Whole. Days – don’t forget the dramatic pauses between words – try reading it again like that). The fat restricted group lost 89 grams of fat per day compared to the 53.6 grams of fat per day in the carb restricted group.
The Problems with the Study
Nineteen subjects – not enough to make me say, “yup, everyone is going to act this way.”
Six days – because obesity only lasts six days, right? (again, don’t forget to read it as if it were dripping with sarcasm.) Besides, ketoadaptation and stimulation of fat metabolism takes longer than 6 days – therefore a longer study is needed to truly answer the question.
While the calculated fat loss was higher in the fat restricted group, the gold standard of body fat measurement, DEXA scanning, did not show a significant difference between the two groups.
Lastly, while the fat restricted diet was truly “low fat” – 17 g of fat per day (8% of total calories). The carb restricted diet was on average 140 g of carbs per day. The induction phase of Atkin’s is 20 g of carbs or less. “Low Carb” is 40 g of carbs or less. And controlled carbs is 75 g of carbs or less. The study didn’t look at real world low carb vs low fat diets – it wasn’t a fault of their study, it just wasn’t what they were going for.
So, the study was: too small, too short, and didn’t compare low fat to low carb diets. It didn’t answer the question that the study was not asking. Everyone looking at this study and shouting, “Low Fat Rules!” doesn’t understand the study at all.
An Interesting Thing About the Study
What I found interesting in the study was that fat oxidation (fat burning) was actually higher in the carb restricted group, but that increased fat burning was offset by the increased fat intake making the net fat loss higher in the fat restricted group. Translation – carb restricted folks burned more fat, but took in more fat, so it was a wash.
Another interesting point about this study – they dropped the calories by 800 in each group which led to an ultralow fat diet but a relatively high carb diet. There were still a whole lot of calories to drop – 400 to be specific – to get to “low carb.” I reckon that would drop a fair amount of fat. But again, not the point of the study.
What Does All This Mean?
This study made it clear that a calorie was, in fact, not a calorie. Or should I say, not all calories were created equal and a fat calorie is used by your body differently than a carb calorie. What it didn’t do was declare the winner of Low Carb vs Low Fat.
So what is the best nutrition plan? Now THAT is the question. That is the question that got me serious about this whole weight loss business. What I learned is that the best nutrition plan (low carb vs low fat vs low…) is the one you can stick with. This is also the conclusion of the author of the study.
If your nutrition plan is working for you and you are comfortable with it – Great! If you need some help or advice, give us a call (262-373-0169) or look us up online at Strongweightloss.net