Want to remember this? Post this awesome guide to the best intermittent fasting schedules to your favorite Pinterest board! And don’t forget to follow me on Pinterest
-Mind Your Damn Fitness-
If you’re looking to lose weight and you landed at this post, you’re probably no stranger to intermittent fasting. With health benefits ranging from weight loss, sharpened focus, and increased longevity, the popularity of intermittent fasting has recently skyrocketed. But with so many intermittent fasting schedules to choose from, it may seem complicated to determine which is best for weight loss.
Fortunately, intermittent fasting isn’t one-size-fits-all. Each of the intermittent fasting schedules have their own unique components that appeal to different needs. So it’s really a matter of finding the schedule that fits most seamlessly within your lifestyle.
In this post, I review some of the most popular intermittent fasting schedules to assist you in deciding which approach is best for you.
24-Hour Intermittent Fasting Schedules
One of the most popular 24-hour intermittent fasting schedules is the 5:2 Diet, which is also know as the Fast Diet. This eating pattern calls for a 24-hour fasting interval two days per week. This particular method, however, allows for consumption of a low-calorie diet (roughly 500 calories for women and 600 calories for men) when fasting. There are no restrictions on the types of foods that you can eat to make up the 500-600 calories.
On the other 5 days of the week, you eat normally (no limitations or restrictions). Note that that there should be at least one non-fasting day in between the fasting days.
Across a week, the 5:2 Diet could look like this:
Another popular approach to 24-hour intermittent fasting is the Eat-Stop-Eat protocol. Also known as the 24-Hour Method, this schedule consists of one or two 24-hour fasting intervals per week. If you choose to fast a second day, the fasting days should be separated by at least one non-fasting day.
One of the biggest differences between Eat-Stop-Eat and the 5:2 Diet is that, during the Eat-Stop-Eat fasting interval, no food is allowed. Only water (plain or sparkling), unsweetened coffee or tea, and other non-calorie beverages are permitted. This approach to the fasting intervals is most commonly known as a “water fast” or “wet fast”.
Although there is flexibility in the timing of the 24-hour fasting interval, a common schedule is 5:00 PM one evening through 5:00 PM the next evening.
Across a week, Eat-Stop-Eat could look like this:
Is fasting longer than 24 hours better?
One may logically come to the conclusion that the less time you spend eating (i.e. the longer the fasting interval), the greater potential for weight loss.
To address this question, let’s review the results of several classic fasting studies in Figure 1 below.
These studies evaluated the impact of prolonged fasting on basal metabolic rate. The metabolic rate after a 12-hour overnight fast was used as the baseline. This is marked as “100%” on the graph in Figure 1. An increase above 100 reflects an increase in basal metabolic rate above baseline. And a decrease below 100 reflects a decrease below baseline basal metabolic rate.
For the first 36 hours of fasting (12 hour overnight fast followed by 24 hour fast), basal metabolic rate increased. However, in all but one study, basal metabolic rate started to return back to baseline after this time point. Thus, it appears that the benefit of intermittent fasting on basal metabolic rate starts to diminish after 36 hours.
Changes in resting energy expenditure during early starvation expressed as a percentage of overnight fasted value (indicated as 100% at 12 hours)
Time-restricted feeding includes all intermittent fasting schedules that limit the hours you eat each day. Thus, the fasting intervals are less than 24 hours in length, and generally tend to range anywhere from 12 to 20 hours.
One of the most popular time-restricted schedules is the 16/8 Method (Leangains protocol). 16/8 consists of daily cycles of 16-hour fasting and 8-hour feeding intervals. This basically means you eat all of your meals and snacks during an 8-hour period. You may have also heard this eating pattern referred to as the “8-hour diet”.
During the 8-hour feeding intervals you are free to eat what you want and in the quantities that you want. But for optimal weight management, the best intermittent fasting foods are well-balanced meals that provide good nutrition and help control hunger during fasting periods. This is especially important for the last meal before your fast, as it will help sustain you until you break your fast. For more information, check out this post on what to eat when intermittent fasting.
During the fasting interval, only water (plain or sparkling), unsweetened coffee or tea, and other beverages with no calories are permitted.
Across a week, 16/8 looks like this:
Although there is flexibility in the timing of the 8-hour feeding interval, a common eating schedule is 12:00 PM through 8:00 PM.
Fasting during the earlier part of the day instead of later in the day is generally recommended. Most people find it easier to fast upon waking up in the morning and prefer to go to bed feeling somewhat full. Also, lunch and dinner offer opportunities for social interactions. Thus, fasting later in the day could have negative social implications.
However, you also don’t want to eat too late in the day. Due to circadian rhythm (or sleep/wake cycle), our bodies process food less efficiently overnight. Calories consumed later in the evening (generally after 8:00 PM) are more likely to be stored as fat. Thus, eating too late in the evening could undermine the metabolism-boosting benefits of intermittent fasting.
For more information on getting started with 16/8 intermittent fasting, check out this beginner’s guide to intermittent fasting post.
The Warrior Diet
The Warrior Diet follows the same format as 16/8. But where these two intermittent fasting schedules differ in two important ways: 1) the length of the fasting and feeding intervals and 2) what can be consumed during the fasting intervals.
With the Warrior Diet, you fast for 20 hours per day and consume as much food as you’d like during a 4-hour feeding interval in the evenings. This is eating pattern is followed on a daily basis. However, the 20-hour fasting period is not a true “fast” in the sense that you are allowed (encouraged) to consume small amounts of dairy products, hard-boiled eggs, and raw fruits and vegetables. You should also stay hydrated with plenty of non-calorie liquids (water, black coffee, etc).
Flexible Time-Restricted Eating Schedule
Most Americans eat 15+ hours a day. This only gives your body a 9-hour break from processing food, and this largely occurs during sleep. Thus, there is a lot of room for improvement!
It may come as a relief that you don’t have to fast 16-20 hours per day to lose weight with intermittent fasting.
In fact, studies have shown that you can achieve positive weight loss benefits from as little as 12 hours of fasting per day. In other words, you can still eat for up to 12 hours per day and still reap the benefits of intermittent fasting. Even more, you don’t even have to be perfect. Fasting for 12 hours per day 5 out of 7 days a week may be enough to help you lose weight!
Learn more about a novel intermittent fasting weight loss program that will help you CRUSH your weight loss goals!
Intermittent fasting can be a very powerful weight loss tool! The key is to finding the schedule that fits best with your preferences and lifestyle. So carefully weigh (pun intended) the pros and cons of the various intermittent fasting schedules to pick a method that you can stick with.