IIFYM: If It Fits Your Macros
Flexible dieting that lets you eat what you love while hitting your fitness goals. Track macros, not emotions.
What is IIFYM?
If It Fits Your Macros (IIFYM) is a flexible dieting approach where you track your daily intake of protein, carbohydrates, and fat (macronutrients) rather than restricting specific foods. As long as you hit your macro targets, you can eat anyfoods you want—including pizza, ice cream, and burgers. The 80/20 rule works best: 80% whole foods for health and satiety, 20% treats for adherence and sanity. IIFYM teaches portion control, macro literacy, and food freedom. It's sustainable, science-based, and perfect for cutting, bulking, or maintaining weight.
Macro Calculator
Track your daily macros
Recommendation: 140g (2g/kg)
Recommendation: 56-70g
Your Daily Totals
How IIFYM Works
1. Set Your Macros
Calculate your daily protein, carbs, and fat targets based on your goals (cutting, bulking, or maintaining). Protein is non-negotiable—start there.
2. Track Everything
Use an app like MyFitnessPal or Cronometer to log every meal. Weigh food with a kitchen scale for accuracy (eyeballing doesn't work).
3. Hit Your Targets
Eat any foods you want—as long as you hit your daily macros. Pizza for lunch? Fine. Just make it fit your remaining targets.
The 80/20 Rule
80% whole foods (lean protein, veggies, whole grains, fruits) for health, fiber, and satiety. 20% flexible foods (treats, processed foods) for adherence and mental health. Hitting macros with 100% junk food is technically possible but leaves you starving and nutrient-deficient.
Best Apps for Tracking Macros
MyFitnessPal
Best for: Beginners. Largest food database (14+ million foods), barcode scanner, easy macro tracking. Free version works great.
Cronometer
Best for: Accuracy. Tracks 82 micronutrients, verified food database, detailed reports. Preferred by serious trackers.
MacroFactor
Best for: Advanced users. AI-powered macro adjustments based on your progress. Paid only ($12/month) but worth it.
Lose It!
Best for: Simplicity. Clean interface, photo logging, challenges. Great for those overwhelmed by MyFitnessPal.
Frequently Asked Questions
What is IIFYM (If It Fits Your Macros)?
IIFYM is a flexible dieting approach where you track your macronutrients (protein, carbs, fat) rather than focusing on specific foods. As long as you hit your daily macro targets, you can eat any foods you want—including treats. It's about balance, not restriction.
How do I calculate my macros for IIFYM?
Start with protein: 1.6-2.2g per kg bodyweight. Fat: 0.8-1g per kg. Carbs: fill remaining calories after protein and fat. Example for 70kg person cutting at 1,800 calories: 140g protein (560 cal), 60g fat (540 cal), 175g carbs (700 cal).
Can I really eat junk food on IIFYM?
Yes, but with nuance. The 80/20 rule works best: 80% whole foods (lean protein, veggies, whole grains) for health and satiety, 20% flexible (treats, processed foods) for adherence. Hitting macros with only junk food is technically possible but leaves you hungry and nutrient-deficient.
What apps should I use to track macros?
Top choices: MyFitnessPal (largest food database), Cronometer (most accurate micronutrients), MacroFactor (AI-powered adjustments), Lose It (simple interface). All work well—pick one that feels intuitive to you and stick with it.
Do I need to track macros forever?
No. IIFYM is a tool, not a lifestyle. Track for 8-12 weeks to learn portion sizes and macro content of foods. Many people then transition to intuitive eating, only returning to tracking when cutting or bulking. It's education, not a prison sentence.
Can IIFYM help me lose weight or build muscle?
Yes to both. For fat loss: set calories in a deficit (TDEE - 500) and hit protein (2g/kg) to preserve muscle. For muscle gain: set calories in surplus (TDEE + 300) with high protein (2-2.2g/kg). IIFYM is the tool—calorie balance is the mechanism.
Key Takeaways
- IIFYM = flexible dieting—track macros, not emotions. Eat what you love as long as it fits your daily targets.
- Start with protein (1.6-2.2g/kg bodyweight), then set fat (0.8-1g/kg), and fill remaining calories with carbs.
- Use the 80/20 rule:80% whole foods for health, 20% treats for adherence. Don't eat 100% junk.
- Track with an app (MyFitnessPal, Cronometer, MacroFactor). Weigh food with a kitchen scale for accuracy.
- You don't need to track forever—8-12 weeks teaches you portions. Then you can intuitively eat.
- IIFYM works for fat loss and muscle gain—it's the tool, calorie balance is the mechanism.