Popular Ways to Do Intermittent Fasting
Intermittent fasting has been very trendy in recent years.
It is claimed to cause weight loss, improve metabolic health and perhaps even extend lifespan.
Not surprisingly given the popularity, several different types/methods of intermittent fasting have been devised.
All of them can be effective, but which one fits best will depend on the individual.
Intermittent fasting is fasting on a schedule, alternated with times of eating. For example, you may eat normally for most of the week, but on Tuesdays and Thursdays only eat for an 8-hour period and fast for the remaining 16 hours. Some also call this a fasting-mimicking diet. The body is designed to protect you against starvation. To do this, it stores a reserve of the nutrients needed to survive when you eat.
When you’re not eating normally, this puts the cells under mild stress, and your body begins to release those stores to fuel itself. As long as your body has time to heal itself after this period of stress, you won’t experience negative effects. (Source One of the most immediate results of this type of diet is weight loss, since your body is using more calories than it’s taking in.
It’s important to be careful about fasting for an extended period of time that your body cannot handle. Complete or continuous fasting will trigger “starvation mode,” in which your body starts slowing down to prolong your life. This typically begins after three days of continuous fasting. During this fasting period of more than three days, your body will hold on to fuel stores as much as possible, and you won’t notice weight loss.
Here are 6 popular ways to do intermittent fasting.
1. The 16/8 Method: Fast for 16 hours each day.
The 16/8 Method involves fasting every day for 14-16 hours, and restricting your daily “eating window” to 8-10 hours.
Within the eating window, you can fit in 2, 3 or more meals.
This method is also known as the Leangains protocol, and was popularized by fitness expert Martin Berkhan.
Doing this method of fasting can actually be as simple as not eating anything after dinner, and skipping breakfast.
For example, if you finish your last meal at 8 pm and then don’t eat until 12 noon the next day, then you are technically fasting for 16 hours between meals.
It is generally recommended that women only fast 14-15 hours, because they seem to do better with slightly shorter fasts.
For people who get hungry in the morning and like to eat breakfast, then this can be hard to get used to at first. However, many breakfast skippers actually instinctively eat this way.
You can drink water, coffee and other non-caloric beverages during the fast, and this can help reduce hunger levels.
It is very important to eat mostly healthy foods during your eating window. This won’t work if you eat lots of junk food or excessive amounts of calories.
I personally find this to be the most “natural” way to do intermittent fasting. I eat this way myself and find it to be 100% effortless.
I eat a low-carb diet, so my appetite is blunted somewhat. I simply do not feel hungry until around 1 pm in the afternoon. Then I eat my last meal around 6-9 pm, so I end up fasting for 16-19 hours.
The 16/8 method involves daily fasts of 16 hours for men, and 14-15 hours for women. On each day, you restrict your eating to an 8-10 hour “eating window” where you can fit in 2-3 or more meals.
2. The 5:2 Diet: Fast for 2 days per week.
The 5:2 diet involves eating normally 5 days of the week, while restricting calories to 500-600 on two days of the week.
This diet is also called the Fast diet, and was popularized by British journalist and doctor Michael Mosley.
On the fasting days, it is recommended that women eat 500 calories, and men 600 calories.
For example, you might eat normally on all days except Mondays and Thursdays, where you eat two small meals (250 calories per meal for women, and 300 for men).
As critics correctly point out, there are no studies testing the 5:2 diet itself, but there are plenty of studies on the benefits of intermittent fasting.
The 5:2 diet, or the Fast diet, involves eating 500-600 calories for two days of the week, but eating normally the other 5 days.
3. Eat-Stop-Eat: Do a 24-hour fast, once or twice a week.
Eat-Stop-Eat involves a 24-hour fast, either once or twice per week.
This method was popularized by fitness expert Brad Pilon, and has been quite popular for a few years.
By fasting from dinner one day, to dinner the next, this amounts to a 24-hour fast.
For example, if you finish dinner on Monday at 7 pm, and don’t eat until dinner the next day at 7 pm, then you’ve just done a full 24-hour fast.
You can also fast from breakfast to breakfast, or lunch to lunch. The end result is the same.
Water, coffee and other non-caloric beverages are allowed during the fast, but no solid food.
If you are doing this to lose weight, then it is very important that you eat normally during the eating periods. As in, eat the same amount of food as if you hadn’t been fasting at all.
The problem with this method is that a full 24-hour fast can be fairly difficult for many people.
However, you don’t need to go all-in right away, starting with 14-16 hours and then moving upwards from there is fine.
I’ve personally done this a few times. I found the first part of the fast very easy, but in the last few hours I did become ravenously hungry.
I needed to apply some serious self-discipline to finish the full 24-hours and often found myself giving up and eating dinner a bit earlier.
Eat-Stop-Eat is an intermittent fasting program with one or two 24-hour fasts per week.
4. Alternate-Day Fasting: Fast every other day.
Alternate-Day fasting means fasting every other day.
There are several different versions of this. Some of them allow about 500 calories during the fasting days.
Many of the lab studies showing health benefits of intermittent fasting used some version of this.
A full fast every other day seems rather extreme, so I do not recommend this for beginners.
With this method, you will be going to bed very hungry several times per week, which is not very pleasant and probably unsustainable in the long-term.
Alternate-day fasting means fasting every other day, either by not eating anything or only eating a few hundred calories.
5. The Warrior Diet: Fast during the day, eat a huge meal at night.
The Warrior Diet was popularized by fitness expert Ori Hofmekler.
It involves eating small amounts of raw fruits and vegetables during the day, then eating one huge meal at night.
Basically, you “fast” all day and “feast” at night within a 4 hour eating window.
The Warrior Diet was one of the first popular “diets” to include a form of intermittent fasting.
This diet also emphasizes food choices that are quite similar to a paleo diet – whole, unprocessed foods that resemble what they looked like in nature.
The Warrior Diet is about eating only small amounts of vegetables and fruits during the day, then eating one huge meal at night.
6. Spontaneous Meal Skipping: Skip meals when convenient.
You don’t actually need to follow a structured intermittent fasting plan to reap some of the benefits.
Another option is to simply skip meals from time to time, when you don’t feel hungry or are too busy to cook and eat.
It is a myth that people need to eat every few hours or they will hit “starvation mode” or lose muscle.
The human body is well equipped to handle long periods of famine, let alone missing one or two meals from time to time.
So if you’re really not hungry one day, skip breakfast and just eat a healthy lunch and dinner. Or if you’re travelling somewhere and can’t find anything you want to eat, do a short fast.
Skipping 1 or 2 meals when you feel so inclined is basically a spontaneous intermittent fast.
Just make sure to eat healthy foods at the other meals.
Another more “natural” way to do intermittent fasting is to simply skip 1 or 2 meals when you don’t feel hungry or don’t have time to eat.
Take Home Message
There are a lot of people getting great results with some of these methods.
That being said, if you’re already happy with your health and don’t see much room for improvement, then feel free to safely ignore all of this.
Intermittent fasting is not for everyone. It is not something that anyone needs to do, it is just another tool in the toolbox that can be useful for some people.
Some also believe that it may not be as beneficial for women as men, and it may also be a poor choice for people who are prone to eating disorders.
If you decide to try this out, then keep in mind that you need to eat healthy as well.
It is not possible to binge on junk foods during the eating periods and expect to lose weight and improve health.
Calories still count, and food quality is still absolutely crucial.
For more details on intermittent fasting, read this: Intermittent Fasting 101 – The Ultimate Beginner’s Guide.SHARES
#1 Fasting Within a Daily Window
This is often the most popular way of intermittent fasting, since it’s easier for us to naturally eat this way. For example, someone might skip breakfast and have their first meal at noon, then eat regularly throughout the rest of the day but stop eating at 8pm. This means you’d be eating for an 8-hour period and fasting for 16 hours.
These times are just an example, too. Some people might prefer to start eating later in the day (works especially well for those who are used to skipping breakfast), while others will start earlier and have an early dinner.
The amount of time for this varies. Some people will eat within a small timeframe, such as six-, four-, or even one-hour period, eating only one big meal per day. What’s important to remember here is that no matter when you do eat during the day, you should still get your day’s worth of calories and be mindful of macro and micronutrient needs.
Pros: Most people see the greatest success, and do so healthfully, with this method when sticking to a regular feeding time schedule and making it fit with your lifestyle.
Cons: Other than it possibly taking a little time to adjust to a fasting window that works for you, there aren’t many cons for this method. Just make sure you eat well and eat enough calories during the times you aren’t fasting.
#2 Alternate Days Fasting
This method involves fasting for a few days each week and eating as you normally would for the other days. For example, you could fast on Monday and Wednesday and eat normally the rest of the days out of your week.
Another version of this is the 5-2 method: eating normally five days out of the week and choosing two days to eat around ¼ of your regular caloric intake (which is usually around 500-600 calories for the average person).
Pros: Fasting on alternate days can be really flexible for most people and lets you customize your week. In a small study with 24 women, the 5-2 method was even found to help protect against breast cancer.
Cons: Simply restricting calories on the two days might be harder than just fasting for some people, plus there’s no guarantee it will put you into ketosis. The quality of the food definitely matters, so unless you focus on whole, low-carb foods, the low calorie days can be really uncomfortable.
#3 Skipping a Meal
It’s pretty self-explanatory: just skipping one meal out of your day. For example, you’d just eat two out of the “standard” three meals per day, skipping the usual time for breakfast, lunch, or dinner.
Pros: Simply skipping a meal works well if you’re new to fasting and want to keep it simple. Plus, it’s an easy way to save time and money if you’re traveling or stuck without food for a certain meal.
Cons: Sometimes skipping a meal without proper planning can cause one to overeat on the other meals, so it’s important to fill up on healthy fats and other keto foods to control hunger.
#4 Fat Fasting
Fat fasting is a common way of breaking a weight loss plateau, often for those who are already keto-adapted and in ketosis. Around 80-90% of calories come from fat, and calorie intake is usually kept low.
This can be combined with intermittent fasting, limiting your eating times to a smaller window, for even better results.
Pros: Just like with the ketogenic diet, the high amount of fat helps you stay satisfied and reduces hunger, making the fasting periods much easier than a diet more centric on carbohydrate foods. Plus, it helps guarantee you stay in nutritional ketosis and makes eating choices simpler.
Cons: Fat fasting can be rough, as you might quickly get tired of eating the same foods. Plus, due to the lower calorie intake, it’s not a good idea to do long-term. Fat fasting is meant to be done over a shorter period of time (no more than 3-5 days at a time) for quicker results, so it’s worth it if you can push through it during that time.
#5 The Warrior Diet
The Warrior Diet involves eating a small amount of fruits, vegetables, and and fast-assimilating protein like yogurt or whey protein every few hours and eating one very large meal within the last four hours of your night. If you’re focusing on keto foods, obviously you’d want to forgo the fruit and focus on low-carb vegetables and keto snacks.
Pros: Since small snacks are “allowed” before evening, it can be easier than forgoing food altogether during the day. Some people might also like eating a lot at night. Plus, the diet promotes high-quality foods choices and staying away from added sugars and processed foods.
Cons: The encouragement of a huge feast at night can cause some to overeat and lead to digestion problems from a ton of late-night eating.
#6 24-Hour Fasting
This one is fairly simple. Basically, you just fast from one meal (breakfast, lunch or dinner) to the same meal the next day. For example, you could stop eating after dinner one night and fast until dinner the next evening, or whichever meal works best for you.
It’s best to do this a couple days a week and eat normally the rest of the days.
Pros: This can be a good way to get into ketosis more quickly (taking exogenous ketones can help too) or give your body a good break from food.
Cons: Some people can find this method difficult and might do better beginning with a 12-16 hour fast first before building up their discipline.
#7 Only Eating When Hungry
While this might not be a structured way of “fasting,” it often naturally becomes a fast when you listen to your hunger. Basically, if you aren’t feeling hungry even though it’s “time” for breakfast, just skip it! Or forgo lunch or dinner if you’re not hungry during those times.
Pros: This allows you to listen to your body and also not overeat just because you feel like you must eat because it’s a certain time of day.
Cons: Just like with skipping a meal and the 5-2 method, this type of fasting doesn’t always guarantee ketosis if you aren’t eating keto-friendly — and even then, there’s no way to know for sure unless you’re testing your ketone levels. And as with every fasting method, eating well is a must for the best results.