Your Calorie intake comes from your consumption of macronutrients. A macronutrient is a nutrient you need to consume in relatively large quantities to meet your body’s needs.
The three major macronutrients are protein, carbohydrates, and dietary fat.
A gram of protein provides about 4 Calories
A gram of fat provides about 9 Calories
A gram of carbohydrate provides about 4 Calories
All of these macronutrients provide energy in the form of Calories, but there are some very notable distinctions between them, and they serve very different purposes in our diet.
Two diets containing 2,500 Calories per day could look very different in terms of the types of foods they include, the way they impact body composition, and the way they impact performance, if their macronutrient ratios differ.