Below is an article published by the Annals of  Internal Medicine and presented in the New York Times.  It is offered as cautionary example of the importance of questioning what is often stated as truth.

            http://annals.org/article.aspx?articleid=1900694

And here are my take-home points from the study:

•  The study involved 148 people without diabetes or heart disease, dividing them into two groups, to compare the effect of eating a low carb diet with a low fat diet in reducing weight and in having better cholesterol and triglyceride levels.
• The group that received a low carb diet were to eat <40g carb a day (which is the equivalent of less then 2 apples a day).
• The group that received a low fat diet was to receive <30% of their daily calories from fat.
• Both groups were followed for a maximum of 1 year with frequent dietary counseling during that time.
• The study found that those who ate a lower carb diet had lower levels of triglycerides, steeper rises in HDL (good cholesterol) as well as more weight loss than those in the low fat group, after 1 year.

Now here are my issues with the study. There are many, but for the sake of brevity, I will keep it to 3 important points:

1.  There was no stated important stipulation on what carb to eat in the higher carb/low fat group. In other words, one could have white bread, processed grains, and arguably soda and still be within the guidelines. All these foods mentioned are terrible for health and for many are incredibly pro-inflammatory.  So while a food might be low fat, it doesn’t make it healthy (Remember the “Snackwells” era?).  A bagel just does not have the same nutritional value and effect on the body as a  whole piece of fruit or cooked beans.  Ask any diabetic patient.  Perhaps it would have been more interesting to compare the same high protein group to a low fat group in which the carbs came from unprocessed whole grains, legumes, or fruit.

2. Studies that have shown improvement in inflammation and improvement and even reversal in cardiovascular problems with low fat diets used fat percentages of 10% or less, not 30% or less as in this study. So one could argue that the “low fat” group was not “low fat” at all and again, not a worthy comparison.

3. More important than how quickly one loses unwanted weight is if they are able to KEEP it off.  Anyone who has ever been on a diet knows this. Those on an Atkins/high protein diet often start regaining weight AFTER the 1 year mark. This study ended after 1 year. It would be interesting to continue to follow both groups over time to monitor their progress and see if these diets are sustainable.

Bottom Line

This study was not an accurate comparison between low carb diets and low fat diets because the “low-fat” arm of the study was arguably not on a low fat diet at all, and as stated no clear distinction seems to have been made regarding the choice of carbohydrates. All carbohydrates are definitely not equal in terms of their effect on one’s body and health.