Julia Belloz at Vox – We’ve long blamed carbs for making us fat. What if that’s wrong?
The main scientific model behind the low-carb approach is the “carbohydrate-insulin hypothesis,” which journalist Gary Taubes, Harvard professor David Ludwig, and others have extensively promoted. It suggests that a diet heavy in carbohydrates (especially refined grains and sugars) leads to weight gain because of a specific mechanism: Carbs drive up insulin in the body, causing the body to hold on to fat and suppress calorie burn.
But what’s often lost in all the boosterism around the low-carb approach is that it is still an unproven hypothesis in science.
So they did a study to show whether a low-carb diet can actually help to reduce weight. 17 overweight or obese men in a metabolic chamber for 4 weeks and fed either a high carbohydrate diet or ketogenic diet with the same number of calories. Results? No increased body fat loss with the ketogenic diet.
But as Bazinet points out, “The study … doesn’t see any [relationship between a decrease in insulin and an increase in fat loss]. Show me a better study that supports this.”
There isn’t any, he added.
Tobias urged dieters not to lose sight of the bigger picture. “Low-carb versus low-fat should not be the focus for people selecting a weight loss diet.” The focus, she said, should be on improving the quality of food that people eat instead.