Traditional nutritional wisdom teaches that “A calorie is a calorie”. Whether it comes from carbohydrates, fat or protein, weight gain (and loss) is a simple matter of total calories in minus calories burned. But is it really that simple?
One obvious difference between foods of equal calories is the amount of micronutrients – vitamins, minerals, essential fatty acids, amino acids and fiber – associated with it. If weight loss or maintenance is your goal, you simply can’t afford to eat high-calorie low-nutrient foods. Another difference between foods is how the calories are used – burned for energy or stored as fat. Calories from simple carbohydrates – sugar and refined flour – are more likely to be stored, since carbs stimulate release of insulin which acts as a key to promote fat storage. Carbs also supply the “glyceride” part of triglycerides.
A study published in JAMA in June 2012 discovered a third difference between foods of equal calories – how they affect metabolism. A significant problem with weight management is that after losing weight on a diet, the metabolism slows (referred to as metabolic adaptation) which makes it more difficult to keep it off. This study compared the effects of three different diets on obese people who had just lost weight. All participants were put on each diet for a month: a) low-fat high-carb; b) low glycemic index; and c) low-carb high-fat high-protein. The results showed that the fewer carbs consumed, the smaller the metabolic adaptation. On average, the low-carb group expended only 100 fewer calories than before (and 8 of 21 actually expended more) while the high-carb group expended 400 fewer calories. This 300 calorie difference is equivalent to an hour of moderate exercise. This shows that a low-carb diet gives dieters the best chance at losing weight and keeping it off, and may prevent susceptible people from becoming overweight in the first place.
This study also found that the low-carb diet reduced triglycerides and HDL cholesterol more than the other diets; and improved insulin sensitivity – a measure of insulin resistance believed behind metabolic syndrome – the most.
"What Really Makes Us Fat", Gary Taubes, New York Times, June 30, 2012
“Good science, bad interpretation”, Peter Attia MD, on his blog The Eating Academy
For more information on this or other natural health topics, stop in and talk to Stan; for medical advice consult your licensed health practitioner.