How many calories are in one gram of protein?

One gram of protein contains 4 calories. This is a well-established fact in nutrition science and is important when calculating daily caloric intake from macronutrients. Protein serves several essential functions in the body, including building and repairing tissues, making enzymes and hormones, and supporting overall cellular function.

Knowing that protein has 4 calories per gram helps individuals effectively plan their diets for muscle gain, weight loss, or overall health. For instance, if someone consumes 100 grams of protein, it would contribute 400 calories to their total caloric intake, which is valuable information for managing energy balance and achieving fitness goals.

The other calorie values do not correspond to protein; for example, fats contain 9 calories per gram, and carbohydrates provide 4 calories as well, which can sometimes lead to confusion. Understanding these values allows individuals to better structure their meals and snacks according to their nutritional needs.