Intermittent fasting is one of the most popular approaches to dieting and weight loss.
Although there are all sorts of iterations and variations on intermittent fasting diet patterns, all of the time-restricted eating versions of intermittent fasting involve extending the period of fasting and limiting the window of time that you can consume caloric foods and beverages each day.
For example, 18/6 intermittent fasting involves fasting for 18 hours per day and confining all of your eating to just six hours, while intermittent fasting 20/4 splits the 24-hour day into a 20-hour fast and a 4-hour eating window.
So, what are the different intermittent fasting schedules? How should you schedule your fasting hours with intermittent fasting diets?
In this article, we will discuss different intermittent fasting diet schedules and patterns to help you determine the best intermittent fasting schedule for your needs.
We will cover:
- Common Intermittent Fasting Schedules
Let’s get started!
Common Intermittent Fasting Schedules
Although there are quite a few formalized intermittent fasting schedules, it’s important to note that you can practice intermittent fasting using any schedule that works for you.
For example, two of the more common intermittent fasting schedules are 16/8 intermittent fasting and 18/6 intermittent fasting. In the former, you fast for 16 hours per day and have an eight-hour eating window, whereas, in the latter, you fast for 18 hours a day and have a six-hour eating window.
Either of these intermittent fasting schedules is a viable option, but it is also acceptable to create your own 17/7 intermittent fasting diet. Although this may not be an “official“ intermittent fasting diet schedule, there’s no rule to say that you can’t create an intermittent fasting schedule that deviates from the common ones.
Here are some of the most common intermittent fasting schedules:
The 16/8 Intermittent Fasting Schedule
The 16/8 intermittent fasting diet schedule is probably the most popular version of intermittent fasting. It involves fasting for 16 hours per day with a permissible eating window that lasts eight hours.
This might look something like beginning your overnight fast after dinner at 6 PM and then fasting through the entire night until the next day at 10:00 AM, when you would break your fast with your first meal.
Of course, as with any intermittent fasting diet, you have complete flexibility in terms of how you schedule your 16-hour fast and 8-hour eating window, but something around the 10 AM to 6 PM, 11 AM to 7 PM or noon to 8 PM range is typically what people use for the eating window.
The benefit of the 16/8 intermittent fasting diet schedule is that it is a fairly moderate approach to intermittent fasting, making it more approachable and sustainable for many people.
It doesn’t necessarily involve truncating your eating hours too much more so than you might should you not be following an intermittent fasting schedule, yet it still provides some amount of structure and discipline to cut down on mindless eating, particularly at night.
The 16/8 intermittent fasting diet is a good starting place for beginners because it isn’t too extreme, and it can help you get a sense of how your body responds to an extended period of time without eating.
However, the downside of the 16/8 intermittent fasting diet schedule is that because it is not that much different than the timing for how you would normally consume your meals, the weight loss results and the health benefits of fasting will not be as significant as more aggressive intermittent fasting schedules.
Particularly if your goal is weight loss, it is certainly possible to consume tons of calories over an 8-hour eating window, potentially negating any weight loss.
Therefore, if you are going to practice intermittent fasting using the 16/8 schedule, it is particularly important to be mindful of how many calories you are eating and the quality of your food, just as you would with any weight loss diet.
With that said, the 16/8 intermittent fasting diet schedule is often considered the “sweet spot“ for many people, and they can reasonably get through a daily 16-hour fast without too much physical or mental struggle, yet the eating and fasting schedule provides enough structure and restriction to aid weight loss.
The 18/6 Intermittent Fasting Schedule
The 18/6 intermittent fasting diet is probably the second-most common fasting pattern after intermittent fasting 16/8. It involves fasting 18 hours per day and eating for 6 hours. A common way to split this up is to fast from 6:00 PM to noon the next day or 7:00 PM to 1:00 PM.
This is a great progression for those who have tried 16/8 intermittent fasting and want to limit eating hours even more.
The 12/12 Intermittent Fasting Schedule
One of the easiest intermittent fasting schedules to get started with is 12/12 intermittent fasting.
This intermittent fasting routine involves splitting the 24-hour day into two equal parts: a 12-hour fast and a 12-hour eating window.
You might fast from 7:00 PM to 7:00 AM, 8:00 AM to 8:00 PM, or something similar.
Ultimately, this is a beginner-friendly intermittent fasting schedule because it’s hardly different from a normal ad libitum eating pattern where you’d have the regular overnight fast.
With that said, it won’t be particularly beneficial for controlling caloric intake or providing other health benefits of fasting because the eating window is quite long, and the fasting window is relatively short.
The 14/10 Intermittent Fasting Schedule
After you get accustomed to 12/12 intermittent fasting, you can progress to 14/10 intermittent fasting, which involves a 14-hour fast and a 10-hour eating window.
20/4 Intermittent Fasting (Warrior Diet)
The 20/4 intermittent fasting diet is also called the “Warrior Diet,” which was created by Ori Hofmekler. Following a daily eating and fasting schedule that involves a 20-hour fast and a four-hour eating window, the “Warrior Diet” intermittent fasting routine is so named because it is said to be inspired by the eating habits of the ancient Roman and spartan warriors.
This is a rather aggressive and challenging intermittent fasting routine, as a 20-hour fast per day is quite challenging.
For example, you might begin your overnight fast at 6 PM and continue to fast all the way until 2 PM the next day, when you would be able to have your first meal.
Consuming all of your daily calories in a 4-hour window can also be challenging, depending on your caloric needs and lifestyle.
With that said, if you want to lose weight and need a lot of structure and control around how often you can eat, and you want to capitalize on some of the benefits of fasting, such as improved cardiometabolic health and decreased inflammation, the 20/4 intermittent fasting schedule can be an excellent alternative instead of alternate day fasting.
If you do want to take on this fasting schedule with your diet, it is best to start with a more moderate fasting schedule, like the 16/8 intermittent fasting diet, and then move on to this one when you are ready.
The 24-Hour Fasting Schedule
The 24-hour fasting schedule doesn’t necessarily entail not eating for a whole day, but it does mean not eating for 24 hours.
You can fast from finishing dinner at 7:00 PM one night to 7:00 PM the next. Ultimately, this intermittent fasting routine works out to one meal a day, like the OMAD diet.
If you are strict with the routine, your windows will slowly shift later and later as it will take time to eat your meal and then start the fast.
The 24-hour fasting routine is certainly one of the most aggressive intermittent fasting schedules and may not be healthy or sustainable for many people.
Alternate Day Fasting
In addition to the time-restricted eating intermittent fasting schedules, there is also alternate-day intermittent fasting, which involves a full 24-hour water fast every other day and normal eating on the off days.
This is a very challenging fasting routine and not fit for everyone, but there can be benefits of 24-hour water fasting, so it works well for some people.
Ultimately, particularly if you are interested in a stricter intermittent fasting schedule, it’s important to speak with your healthcare provider before you start extended fasting every day to make sure that it is a safe and effective option for you.
Experiment and see what type of fasting regimen helps you feel your best and achieve your weight loss and health goals.
For more information on water fasts, check out our helpful guides, such as:
The 24 Hour Water Fast: Complete Guide
The 2 Day Water Fast: The Complete Guide
The 5 Day Water Fast: The Complete Guide
I have had success with 18/6, I run early morning after a coffee and come back to a full breakfast. Works for people that don’t feel hungry when they wake up.
I don’t recommend eating within three hours of going to bed, the digestive process will probablt disturb your sleep.