Macronutrients ("macros") are the three nutrient groups that provide calories and energy:
- Protein — 4 calories/gram. Builds and repairs muscle, produces hormones and enzymes.
- Carbohydrates — 4 calories/gram. Primary energy source for the brain and muscles.
- Fats — 9 calories/gram. Supports hormone production, vitamin absorption, and cell membranes.
Common Macro Splits
- Balanced: 40% carbs, 30% protein, 30% fat
- Low-carb/keto: 5–10% carbs, 20–25% protein, 65–75% fat
- High-protein (muscle gain): 40% carbs, 35% protein, 25% fat
Macros vs. Micronutrients
Macronutrients (protein, carbs, fat) provide calories and are needed in large quantities. Micronutrients (vitamins and minerals) are needed in much smaller amounts and provide no calories, but are just as essential — hitting your macro targets doesn't guarantee adequate micronutrient intake, which is why food quality still matters alongside macro tracking.
Alcohol: The Fourth Calorie Source
Alcohol provides 7 calories per gram — between carbs/protein (4) and fat (9) — but isn't classified as a macronutrient since it's not required for bodily function. It's worth accounting for separately when tracking total calorie intake, since it's easy to overlook.