JAMA Network | JAMA: The Journal of the American Medical Association | Effects of Dietary Composition on Energy Expenditure During Weight-Loss MaintenanceDietary Composition During Weight-Loss Maintenance.
This article compares results of 3 different diets, all with the same calories:
- 1. 60% of energy from carbohydrate, 20% from fat, 20% from protein; high glycemic load
- 2. 40% from carbohydrate, 40% from fat, and 20% from protein; moderate glycemic load.
- 3. 10% from carbohydrate, 60% from fat, and 30% from protein; low glycemic load
The results showed that the high carb, high glycemic load diet resulted in the greatest slowdown of our fat-burning due to calorie restriction. The low-carb, high fat diet resulted in the least slowdown of metabolism.
In other words, the low fat, high carb diet is the LEAST effective, while the low carb, high fat diet was the MOST effective for weight loss, by about 300 calories/day, or a pound every 12 days. And, from personal experience, as well as anecdotal information, the higher fat, lower carb diet is the most tolerable without excessive hunger.
The reason for this is that if you have very few carbohydrates, the body undergoes a chemical change that allows the body to burn fat more easily. So, the body sees little difference in eaten fat vs stored fat, so when the fat in your digestive tract is used up, the body is burning stored fat. The result is not the precipitous drop in blood sugar that accompanies high carbohydrate diets, but a much more steady one. When eating very low carbohydrates, one can “forget to eat”, a concept lost on most obese people.
Now this does not mean a diet of bacon, eggs, and cheese is healthy– we need nutrients and fiber from vegetables and fruit, too. But, those vegetables should include greens, cucumbers, summer squash, but avoidance of potatoes, rice, corn, winter squash, and other starchy vegetables. The Paleo Diet is quite sensible and compatible with this concept. Of course, flour and sugar should be avoided, too.
So, forget the traditional food pyramid that talks about carbs and grain and a minimum of fat– it is just plain wrong! It may provide plenty of nutrition, but at the expense of hunger sensations and difficulty in sustaining a weight-loss program. This is especially important for “carbaholics”, who have an exaggerated craving for carbohydrates– sweets, crackers, chips, cookies, etc.