Flexible Dieting: Eating Everything While Reaching Your Goals
Discover flexible dieting (If It Fits Your Macros). No forbidden foods, macro tracking, 80/20 rule. Reach your goals with Voical.
Calorie calculation examples by profile
Woman in deficit, 1600 kcal
Woman at maintenance, 2000 kcal
Man in deficit, 2200 kcal
Man in surplus, 3000 kcal
What is flexible dieting?
Flexible dieting, also known as IIFYM (If It Fits Your Macros), is a nutritional approach that focuses on meeting your macronutrient goals (protein, carbs, fat) rather than eliminating specific foods. No food is forbidden as long as it fits into your daily macros.
The IIFYM principle
IIFYM stands for 'If It Fits Your Macros.' The concept is simple: calculate your protein, carb, and fat needs for your goal (deficit, maintenance, or surplus), then distribute these macros as you wish among foods of your choice.
The 80/20 rule
Most flexible dieters follow the 80/20 rule: 80% of food comes from nutritious, unprocessed sources (meat, fish, vegetables, fruits, whole grains), and 20% can come from treat foods (desserts, snacks, fast food). This flexibility makes the approach sustainable.
Tracking macros, not restriction
Flexible dieting isn't a rule-free diet. It requires precise macronutrient tracking. The difference from traditional diets: instead of lists of forbidden foods, you have numbers to hit. This quantitative approach is more objective and allows for individual flexibility.
Important
Never go below 1200 kcal/day (women) or 1500 kcal/day (men) without medical supervision. Too aggressive a deficit can be dangerous for your health and counterproductive for weight loss.
Complete Guide to Flexible Dieting (IIFYM)
Flexible dieting revolutionizes the nutritional approach by eliminating forbidden foods. This guide explains how to apply it effectively.
Understanding Flexible Dieting
The Philosophy
Traditionally, diets classify foods as “good” and “bad.” Flexible dieting rejects this view:
- No forbidden foods: Everything can fit in your diet
- Focus on macros: The totals are what count
- Flexibility: Adapt your diet to your life, not the reverse
- Sustainability: An approach maintainable long-term
IIFYM: If It Fits Your Macros
The central concept: as long as your protein, carb, and fat totals match your goals, the source matters little from a strictly caloric standpoint.
Example:
- 50g carbs from brown rice = 50g carbs from white bread = 50g carbs from cookies
- Calorically equivalent, but nutritionally different
That’s where the 80/20 rule comes in.
The 80/20 Rule in Practice
The 80%: Nutritious Foods
The base of your diet:
- Proteins: Chicken, fish, eggs, legumes, tofu
- Carbs: Rice, potatoes, oats, fruits, vegetables
- Fats: Olive oil, avocado, nuts, fatty fish
These foods provide:
- Micronutrients (vitamins, minerals)
- Fiber for satiety and digestion
- Volume for fewer calories
The 20%: Treat Foods
Space for flexibility:
- Occasional desserts
- Restaurant meals
- Favorite snacks
- Alcohol (in moderation)
This margin allows:
- Maintaining a normal social life
- Avoiding frustration and binges
- Making the approach sustainable
Practical 20% Calculation
For 2000 kcal/day:
- 80% = 1600 kcal from nutritious foods
- 20% = 400 kcal of flexibility
400 kcal allows for example:
- 1 slice of pizza
- 2 scoops of ice cream
- 1 chocolate bar + 1 small dessert
- 2 glasses of wine
How to Calculate Your Macros
Step 1: Determine Your Calories
Calculate your TDEE then apply your goal:
- Deficit: TDEE - 300 to 500 kcal
- Maintenance: TDEE
- Surplus: TDEE + 200 to 300 kcal
Step 2: Calculate Protein
Absolute priority for muscle preservation:
- Minimum: 0.7g/lb body weight
- Optimal (athletes): 0.9-1.0g/lb
- Each gram = 4 kcal
Step 3: Calculate Fat
Essential for hormones and health:
- Minimum: 0.2g/lb (never go below)
- Recommended: 0.3-0.4g/lb
- Each gram = 9 kcal
Step 4: Calculate Carbs
Remaining calories go to carbs:
- Carbs = (Total Calories - Protein Calories - Fat Calories) / 4
- Each gram = 4 kcal
Complete Example
Woman 143 lbs, deficit goal, 1700 kcal:
| Macro | Calculation | Grams | Calories |
|---|---|---|---|
| Protein | 143 x 0.9 = 129g | 130g | 520 kcal |
| Fat | 143 x 0.35 = 50g | 55g | 495 kcal |
| Carbs | (1700 - 520 - 495) / 4 | 171g | 685 kcal |
Tracking Macros Effectively
Level 1: Beginner
Start simple:
- Week 1-2: Track only total calories
- Week 3-4: Add protein tracking
- Week 5+: Include fat and carbs
Level 2: Intermediate
- Track all meals
- Aim for +/-10% of target macros
- Use a food scale for precision
Level 3: Advanced
- Estimate portions visually
- Adjust intuitively
- Track occasionally to verify
Common Mistakes
1. Too Much 20%, Not Enough 80%
The 20% becomes 40% without realizing. Result: nutritional deficit despite hitting macros.
2. Neglecting Micronutrients
Macros don’t tell the whole story. Vitamins, minerals, and fiber matter for health.
3. Number Obsession
Tracking is a tool, not an end. If it creates anxiety, simplify.
4. Forgetting Satiety
100 kcal of broccoli vs 100 kcal of candy: same calories, radically different satiety.
Flexible Dieting and Results
For Weight Loss
- Caloric deficit = weight loss, regardless of source
- The 80/20 helps maintain deficit without frustration
- Precise tracking = no “hidden calories”
For Muscle Gain
- Caloric surplus = weight gain
- Adequate protein = maximize muscle
- Flexibility = easier to reach high surplus
For Maintenance
- Tracking becomes less strict
- Acquired habits guide choices
- Periodic checking maintains balance
Voical and Flexible Dieting
Flexible dieting relies on precise macro tracking. Voical simplifies this process:
- Photograph your meal, macros are calculated automatically
- Visualize your progress toward daily goals
- Easily identify if you’re in your 80% or 20%
In 15 seconds per meal, you have the data needed to practice flexible dieting effectively. No more tedious calculations, no more excuses not to track.