The easiest entry point to intermittent fasting. Matches your natural sleep cycle.
12 hours
Fasting Window
12 hours
Eating Window
400
Est. Weekly Deficit (cal)
~0.11 lbs
Est. Loss per Week
The 12:12 protocol means fasting for 12 hours and eating within a 12-hour window every day. For most people this requires almost no lifestyle change since the fast overlaps entirely with sleep. It is the ideal starting point for anyone new to structured meal timing. Research shows even this modest time restriction can improve insulin sensitivity and reduce late-night calorie intake.
Pick a 12-hour eating window that fits your schedule, such as 7am to 7pm. Eat only within that window and consume only water, plain coffee, or plain tea outside of it. Your overnight fast already covers most of the 12 hours, so you may only need to skip a late-night snack or push breakfast back slightly. The simplicity is the point.
| Day | Eating | Fasting |
|---|---|---|
| Monday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Tuesday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Wednesday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Thursday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Friday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Saturday | 7:00am to 7:00pm | 7:00pm to 7:00am |
| Sunday | 7:00am to 7:00pm | 7:00pm to 7:00am |
Complete beginners to intermittent fasting who want a risk-free starting point
People looking to break the habit of late-night eating without dramatic changes
Anyone wanting to add structure to their eating without tracking calories
People who need to lose weight quickly. The 12:12 window is too modest to produce significant calorie restriction on its own without also controlling food quality and quantity.
Intermittent fasting is an eating-window schedule, not a diet in itself. It helps mainly by making a calorie deficit easier to hold: fewer eating hours often means fewer calories. The research shows it works about as well as continuous calorie restriction for fat loss when total calories and protein are matched, with no strong metabolic magic beyond that.
It is not for everyone. People with a history of disordered eating, those who are pregnant or breastfeeding, and anyone managing blood sugar or medication timing should talk to a clinician first. These pages are educational, not medical advice, and are reviewed by Andrew Menechian, Head of Fitness; see the full methodology for sources.
FitCommit AI food camera makes it easy to hit your macro targets within your eating window. Scan meals, track nutrition automatically, and ensure you get enough protein and calories during your feeding hours.
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Intermittent fasting controls when you eat. What you eat during the eating window still determines whether you lose fat, maintain muscle, or stall entirely. The most effective approach is scanning your meals with FitCommit as you eat, so you know your daily protein, calorie, and macro totals without logging every ingredient manually. Point your camera at your plate, and the AI identifies the meal and calculates the nutrition in seconds.
Tracking your eating window nutrition takes less than two minutes per day and eliminates the guesswork that causes most IF practitioners to either undereat protein (causing muscle loss) or overeat calories (negating the fast). The combination of a proven fasting schedule and accurate nutrition tracking produces results that neither approach achieves alone.
Track Your Eating Window with FitCommitStart by pushing your breakfast back by one hour each week until you reach your target fasting window. During the fasting period, stay hydrated with water, black coffee, or plain tea. Track your eating window with a fasting app or phone timer so you know exactly when to start and stop eating. Most people find it easiest to schedule their fast to overlap with sleep.
Hunger during a fast usually peaks at the times you would normally eat, then fades within 20 to 30 minutes. Drink 500ml of water when hunger hits. Black coffee and plain tea are also effective appetite suppressants and do not break a fast. After one to two weeks, most people find hunger during the fast significantly decreases as their body adapts to the new meal timing.
Anything with calories breaks a fast. This includes milk or cream in coffee, fruit juice, protein shakes, gum with sugar, and any food regardless of how small. Plain water, black coffee, plain herbal tea, and sparkling water (unflavored) do not break a fast and are fine during the fasting window.
Yes. Black coffee, plain green tea, and plain herbal teas are all permitted during the fasting window. They do not meaningfully affect insulin or break ketosis. Do not add milk, cream, sugar, flavored syrups, or MCT oil. Even small amounts of fat or protein will end your fast.
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