6 Reasons Why a Calorie Is Not a Calorie

"Different foods go through different biochemical pathways, some of which are inefficient and cause energy (calories) to be lost as heat .

Even more important is the fact that different foods and macronutrients have a major effect on the hormones and brain centers that control hunger and eating behavior.

The foods you eat can have a huge impact on the biological processes that control when, what and how much you eat.

1. Fructose vs Glucose
Even though fructose and glucose provide the same number of calories, fructose has far more negative effects on hormones, appetite and metabolic health.
2. The Thermic Effect of Food
Protein calories are less fattening than calories from carbs and fat, because protein takes more energy to metabolize. Whole foods also require more energy to digest than processed foods.
3. Protein Kills Appetite and Makes You Eat Fewer Calories
Increased protein can lead to drastically reduced appetite and cause automatic weight loss without the need for calorie counting or portion control.
4. The Satiety Index
Different foods have different effects on satiety and how many calories you end up consuming in subsequent meals. This is measured on a scale called the satiety index.
5. Low-Carb Diets Lead to Automatic Calorie Restriction
Low-carb diets consistently lead to more weight loss than low-fat diets, even when calories are matched between groups.
6. The Glycemic Index
Studies show that refined carbohydrates lead to faster and bigger spikes in blood sugar, which leads to cravings and increased food intake.

https://www.healthline.com/nutrition/6-reasons-why-a-calorie-is-not-a-calorie