Complete Guide to Intermittent Fasting Schedules
16:8, 18:6, 20:4, OMAD — which schedule is right for you? Here's everything you need to know about intermittent fasting.
What is Intermittent Fasting?
Intermittent fasting (IF) is an eating pattern where you cycle between periods of eating and fasting. It's not a diet that tells you what to eat, but when to eat.
The key concept: time-restricted eating. You eat all your calories within a specific window and fast the rest of the day.
Important Note
IF doesn't magically burn more fat. It works by making it easier to eat fewer calories. If you eat the same calories in a shorter window, you won't lose more weight.
The Most Popular IF Schedules
16:8 (Most Popular)
Fast 16 hours, eat within 8 hours
Example: Eat 12pm - 8pm, fast 8pm - 12pm
Best for:
- Beginners to IF
- People who don't like breakfast
- Sustainable long-term
- Social eating flexibility
18:6
Fast 18 hours, eat within 6 hours
Example: Eat 1pm - 7pm, fast 7pm - 1pm
Best for:
- Those comfortable with 16:8 wanting more
- People who prefer 2 larger meals
- Good balance of restriction and flexibility
20:4 (Warrior Diet)
Fast 20 hours, eat within 4 hours
Example: Eat 4pm - 8pm, fast 8pm - 4pm
Best for:
- Experienced fasters
- People who prefer one large meal + snack
- Those with busy schedules
Caution:
- Hard to get adequate nutrition in 4 hours
- May trigger binge eating in some
OMAD (One Meal a Day)
Fast ~23 hours, eat within ~1 hour
Example: One large meal at 6pm daily
Best for:
- Advanced fasters
- Simplicity lovers (no meal planning)
- Those who enjoy large, satisfying meals
Caution:
- Very difficult to meet protein needs
- Risk of undereating and muscle loss
- Can trigger binge/restrict cycles
- Not sustainable for most people
5:2 Diet
Eat normally 5 days, restrict to 500-600 cal for 2 days
Example: Normal eating Mon-Fri, 500 cal Sat-Sun
Best for:
- Those who struggle with daily restriction
- People who want flexibility most days
- Creates weekly deficit without daily tracking
Comparison Chart
| Schedule | Difficulty | Sustainability | Best For |
|---|---|---|---|
| 16:8 | Easy | High | Beginners |
| 18:6 | Moderate | High | Intermediate |
| 20:4 | Hard | Medium | Experienced |
| OMAD | Very Hard | Low | Short-term only |
| 5:2 | Moderate | High | Flexible lifestyles |
Benefits of Intermittent Fasting
- Simplifies eating — Fewer meals to plan and prep
- Naturally reduces calories — Less eating time = less eating
- Improves hunger awareness — Learn true hunger vs. boredom
- May improve insulin sensitivity — Beneficial for metabolic health
- Flexibility — Eat larger, more satisfying meals
- Mental clarity — Some report better focus while fasting
What to Eat During Your Window
IF doesn't give you permission to eat junk. Focus on:
- Protein first — 30-40g per meal minimum
- Fiber-rich vegetables — Fill up on volume
- Whole foods — Minimize processed foods
- Adequate fats — For satiety and hormonal health
- Hydration — Drink extra water during fasting
What Breaks a Fast?
Won't Break Your Fast
- • Water (plain or sparkling)
- • Black coffee
- • Plain tea
- • Zero-calorie drinks
- • Apple cider vinegar
- • Salt/electrolytes
Will Break Your Fast
- • Any food
- • Coffee with cream/sugar
- • Milk (any type)
- • BCAAs
- • Bone broth
- • Anything with calories
How to Start
- Start with 12:12 — Stop eating after dinner, eat breakfast 12 hours later
- Push to 14:10 — Delay breakfast by 1-2 hours
- Progress to 16:8 — Skip breakfast entirely
- Stay there or go further — 16:8 is plenty effective
- Be flexible — Adjust timing to your lifestyle
Common Mistakes
- Overeating during eating window — IF still requires calorie awareness
- Starting too aggressive — Don't jump straight to OMAD
- Ignoring protein — Prioritize protein in your meals
- Not drinking enough water — Stay extra hydrated while fasting
- Being too rigid — It's okay to adjust timing occasionally
- Using IF to justify junk food — Quality still matters
Who Should NOT Do IF
- Pregnant or breastfeeding women
- People with history of eating disorders
- Type 1 diabetics (consult doctor first)
- Those who get severe blood sugar drops
- Anyone who finds it increases food obsession
- People taking medications that require food
Key Takeaways
- • Start with 16:8 — it's effective and sustainable
- • IF works by making it easier to eat less, not magic
- • Calories still matter during your eating window
- • Prioritize protein and whole foods
- • Be flexible — adjust timing to your life
Plan Your Fasting Schedule
Use our IF calculator, then track your meals with Pandish.