> You can't not lose weight if you burn more calories than you eat.
True. However, you can eat less and not lose weight, or eat more and not gain weight, because while Calories Consumed = Calories Stored + Calories Expended, by the laws of thermodynamics, the variables are not independent. If you exercise more, your body acts to try to get you to consume more calories -- and if you don't, by making you not want to expend energy the rest of the day (some studies of kids exercise programs show that the kids become more sedentary the rest of the day). Further, the type of calorie consumed affects the balance of the other side of the equation as well.
20 calories a day is theoretically 40 pounds of fat over 20 years, but nobody can perfectly maintain their caloric input to within exactly 20 calories of maintenance level a day -- our body guides us with signals and changes our metabolism. The arguments about things like fat, carbs, etc. are that the wrong foods mess with these signals and the metabolism in ways that make it substantially harder to stay at a healthy weight or to lose weight.
>Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance
>The results of our study challenge the notion that a calorie is a calorie from a metabolic perspective. During isocaloric feeding following weight loss, REE was 67 kcal/d higher with the very low-carbohydrate diet compared with the low-fat diet. TEE differed by approximately 300 kcal/d between these 2 diets, an effect corresponding with the amount of energy typically expended in 1 hour of moderate-intensity physical activity
>In conclusion, our study demonstrates that commonly consumed diets can affect metabolism and components of the metabolic syndrome in markedly different ways during weight-loss maintenance, independent of energy content. The low-fat diet produced changes in energy expenditure and serum leptin42- 44 that would predict weight regain. In addition, this conventionally recommended diet had unfavorable effects on most of the metabolic syndrome components studied herein. In contrast, the very low-carbohydrate diet had the most beneficial effects on energy expenditure and several metabolic syndrome components, but this restrictive regimen may increase cortisol excretion and CRP.
True. However, you can eat less and not lose weight, or eat more and not gain weight, because while Calories Consumed = Calories Stored + Calories Expended, by the laws of thermodynamics, the variables are not independent. If you exercise more, your body acts to try to get you to consume more calories -- and if you don't, by making you not want to expend energy the rest of the day (some studies of kids exercise programs show that the kids become more sedentary the rest of the day). Further, the type of calorie consumed affects the balance of the other side of the equation as well.
20 calories a day is theoretically 40 pounds of fat over 20 years, but nobody can perfectly maintain their caloric input to within exactly 20 calories of maintenance level a day -- our body guides us with signals and changes our metabolism. The arguments about things like fat, carbs, etc. are that the wrong foods mess with these signals and the metabolism in ways that make it substantially harder to stay at a healthy weight or to lose weight.
http://jama.jamanetwork.com/article.aspx?articleid=1199154
>Effects of Dietary Composition on Energy Expenditure During Weight-Loss Maintenance
>The results of our study challenge the notion that a calorie is a calorie from a metabolic perspective. During isocaloric feeding following weight loss, REE was 67 kcal/d higher with the very low-carbohydrate diet compared with the low-fat diet. TEE differed by approximately 300 kcal/d between these 2 diets, an effect corresponding with the amount of energy typically expended in 1 hour of moderate-intensity physical activity
>In conclusion, our study demonstrates that commonly consumed diets can affect metabolism and components of the metabolic syndrome in markedly different ways during weight-loss maintenance, independent of energy content. The low-fat diet produced changes in energy expenditure and serum leptin42- 44 that would predict weight regain. In addition, this conventionally recommended diet had unfavorable effects on most of the metabolic syndrome components studied herein. In contrast, the very low-carbohydrate diet had the most beneficial effects on energy expenditure and several metabolic syndrome components, but this restrictive regimen may increase cortisol excretion and CRP.