nutrition
Macronutrient
The three calorie-providing nutrients: protein (4 kcal/g), carbohydrates (4 kcal/g), and fat (9 kcal/g).
Macronutrients are the three energy-yielding categories of food: protein, carbohydrates, and fat. Alcohol (7 kcal/g) is sometimes counted as a fourth. Each has distinct metabolic roles: protein supports muscle protein synthesis, carbs fuel high-intensity activity, and fats support hormone production. Fat loss outcomes are driven more by total calories and protein than specific carb/fat ratios, but individual adherence often favors one split over another.