If you’ve ever heard phrases like “count your macros” or “macro split,” you’ve probably wondered—what exactly are macros, and why do they matter so much in fitness?
Whether you’re trying to build muscle, lose fat, or simply improve your energy and health, understanding macronutrients (macros) is a powerful tool.
This guide will break down the basics of protein, carbohydrates, and fats—what they do, how much you need, and how to use them to fuel your goals.
✅ What Are Macros?
Macronutrients are the nutrients your body needs in large amounts to function properly. There are three main macros:
- Protein
- Carbohydrates
- Fats
Each macro provides energy (calories), plays unique roles in the body, and affects your performance, mood, and physique.
| Macronutrient | Calories per gram | Primary Role |
|---|---|---|
| Protein | 4 kcal | Build & repair tissue |
| Carbs | 4 kcal | Energy source |
| Fats | 9 kcal | Hormone regulation & absorption |
🥩 Protein: The Builder Macro
Protein is essential for building and repairing tissues—especially muscle. It’s made up of amino acids, which are like building blocks your body uses to grow and maintain lean tissue.
🔑 Why You Need Protein:
- Repairs muscle after workouts
- Supports immune function
- Helps with satiety (keeps you full)
- Prevents muscle loss during fat loss
🍳 Best Protein Sources:
- Chicken, turkey, lean beef
- Eggs and egg whites
- Fish and seafood
- Greek yogurt, cottage cheese
- Plant-based: lentils, tofu, tempeh, beans, edamame
- Protein powders (whey, casein, pea, etc.)
📏 How Much Protein Do You Need?
Depends on your goal and body weight:
- General health: 0.8–1g per kg of body weight
- Muscle gain: 1.6–2.2g per kg
- Fat loss: 2.0–2.5g per kg (to preserve muscle)
Example:
If you weigh 70kg and want to build muscle:
→ 70 × 2 = 140g protein/day
🍞 Carbohydrates: The Fuel Macro
Carbs are your body’s main energy source, especially during workouts. They’re broken down into glucose and stored as glycogen in muscles and the liver.
🔑 Why You Need Carbs:
- Fuel for exercise and brain function
- Help spare muscle protein from being used for energy
- Aid recovery and replenish glycogen post-workout
🍚 Best Carbohydrate Sources:
- Whole grains: oats, rice, quinoa, barley
- Fruits: bananas, apples, berries
- Vegetables: sweet potatoes, carrots, broccoli
- Legumes: beans, lentils, chickpeas
- Dairy: milk, yogurt
- Pre/post-workout: rice cakes, dates, dextrose powder
🧁 Avoid Excess of:
- Refined sugar, soda, processed pastries—can lead to energy crashes and fat gain if overeaten
📏 How Many Carbs Do You Need?
Carbs are the most variable macro and depend on your training and goal.
- Fat loss (low-carb): 2–3g per kg
- Moderate training: 4–6g per kg
- Endurance/athletes: 6–10g per kg
Example:
If you weigh 70kg and moderately train:
→ 70 × 5 = 350g carbs/day
🥑 Fats: The Hormone Helper Macro
Fats have been wrongly demonized in the past, but they’re vital for hormone production, brain health, and nutrient absorption (especially vitamins A, D, E, K).
🔑 Why You Need Fats:
- Regulate hormones like testosterone and estrogen
- Support brain and nerve health
- Aid in absorption of fat-soluble vitamins
- Provide long-lasting energy
🥥 Best Fat Sources:
- Avocados
- Nuts and seeds (almonds, chia, flax)
- Nut butters
- Olive oil, coconut oil
- Fatty fish (salmon, sardines)
- Whole eggs
🧀 Limit Intake Of:
- Trans fats (in packaged snacks and fried foods)
- Excess saturated fat (processed meats, full-fat dairy)
📏 How Much Fat Do You Need?
Fat should make up about 20–35% of your total daily calories.
A common recommendation:
0.8–1g per kg of body weight
Example:
If you weigh 70kg:
→ 70g fat/day = 630 calories
🔄 How to Balance Your Macros (Macro Split)
Your macro ratio depends on your goal:
🏋️♂️ For Muscle Gain:
- Protein: 25–30%
- Carbs: 45–55%
- Fats: 20–25%
🔥 For Fat Loss:
- Protein: 30–40%
- Carbs: 20–30%
- Fats: 25–35%
🏃♂️ For Endurance:
- Protein: 15–20%
- Carbs: 50–65%
- Fats: 15–25%
🧠 Pro Tips for Macro Tracking
- Use a tracker app: MyFitnessPal, Cronometer, or Macrofactor help track macros accurately.
- Weigh your food (at least in the beginning) to understand portions.
- Prioritize protein first, then fit in carbs and fats based on your goal.
- Stick to whole, minimally processed foods 80–90% of the time.
❗ Common Macro Myths
- “Carbs make you fat” – Only excess calories do.
- “You don’t need fat if you’re cutting” – You do, for hormones and energy.
- “Protein damages kidneys” – Not true unless you have pre-existing kidney issues.
🧮 Quick Macro Cheat Sheet
Here’s what 25g of each macro looks like:
| Macro | 25g Looks Like |
|---|---|
| Protein | ~100g chicken breast |
| Carbs | ~1 cup cooked rice |
| Fats | ~2 tbsp peanut butter |
📌 Final Thoughts
Understanding macros puts the control in your hands. Instead of blindly following a meal plan, you’ll know:
- What your body needs
- Why it needs it
- How to fuel your performance and physique goals
Whether you’re cutting, bulking, or just maintaining, mastering your macros will make your nutrition more flexible, effective, and sustainable.
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