Intermittent fasting has recently become a health trend. Devotees claim it can cause weight loss, improve metabolic health, and maybe even extend life span.
Every method can be effective, but figuring out which one works best depends on the individual.
Several methods of this eating pattern exist. But before embarking on an intermittent fast or deciding how often to fast, you should speak with a healthcare professional.
Here are 6 popular ways to do intermittent fasting.
1. The 16/8 method
The 16/8 method involves fasting every day for about 16 hours and restricting your daily eating window to approximately 8 hours.
Suggested read: 16/8 intermittent fasting: A beginners guide
Within the eating window, you can fit in two, three, 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 be as simple as not eating anything after dinner and skipping breakfast.
For example, if you finish your last meal at 8 p.m. and don’t eat until noon the next day, you’re technically fasting for 16 hours.
For people who get hungry in the morning and like to eat breakfast, this method may be hard to get used to. However, many breakfast skippers instinctively eat this way.
You can drink water, coffee, and other zero-calorie beverages during the fast, which can help reduce feelings of hunger.
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It’s very important to primarily eat healthy foods during your eating window. This method won’t work if you eat lots of processed foods or an excessive number of calories.
Summary: The 16/8 method involves daily fasts of about 16 hours. Each day you’ll restrict your eating to an approximately 8-hour window during which you fit in two, three, or more meals.
2. The 5:2 diet
The 5:2 diet involves eating what you typically eat 5 days of the week and restricting your calorie intake to 500–600 for 2 days of the week.
This diet is also called the Fast Diet and was popularized by British journalist Michael Mosley.
On the fasting days, it’s recommended that women eat 500 calories and men eat 600.
For example, you might eat normally every day of the week except Mondays and Thursdays. For those 2 days, you eat 2 small meals of 250 calories each for women and 300 calories each for men.
The 5:2 diet has been found to be effective at helping with weight loss.
Summary: The 5:2 diet, or the Fast Diet, involves eating 500–600 calories for 2 days out of the week and eating normally the other 5 days.
3. “Eat Stop Eat”
“Eat Stop Eat” involves a 24-hour fast once or twice per week.
This method was popularized by fitness expert Brad Pilon and has been quite popular for a few years.
Fasting from dinner one day to dinner the next day amounts to a full 24-hour fast.
For example, if you finish dinner at 7 p.m. Monday and don’t eat until dinner at 7 p.m. Tuesday, you’ve completed a full 24-hour fast. You can also fast from breakfast to breakfast or lunch to lunch — the result is the same.
Water, coffee, and other zero-calorie beverages are allowed during the fast, but no solid foods are permitted.
If you’re doing this to manage your weight, you must stick to your regular diet during the eating periods. In other words, you should eat the same amount of food as if you hadn’t been fasting at all.
The potential downside of this method is that a full 24-hour fast may be fairly difficult for many people. However, you don’t need to go all-in right away. It’s fine to start with 14–16 hours and then move upward from there.
Summary: “Eat Stop Eat” is an intermittent fasting program with one or two 24-hour fasts per week.
4. Alternate-day fasting
In alternate-day fasting, you fast about every other day.
There are several different versions of this method. Some of them allow about 500 calories during the fasting days.
However, one small study found that alternate-day fasting wasn’t any more effective at producing weight loss or weight maintenance than a typical calorie-restrictive diet.
A full fast every other day can seem rather extreme, so it’s not recommended for beginners.
With this method, you may go to bed very hungry several times per week, which is not very pleasant and probably unsustainable in the long term.
Summary: Alternate-day fasting involves fasting about every other day, either by not eating anything or by eating only a few hundred calories.
5. The warrior diet
The warrior diet was popularized by fitness expert Ori Hofmekler.
It involves eating small amounts of raw fruits and vegetables during the day and eating one huge meal at night.
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’s food choices are quite similar to those of the paleo diet — mostly whole, unprocessed foods.
Summary: The warrior diet encourages subsisting on only small amounts of vegetables and fruits during the day and then eating one huge meal at night.
6. Spontaneous meal skipping
You don’t need to follow a structured intermittent fasting plan to reap some of its benefits. Another option is to simply skip meals from time to time, such as when you don’t feel hungry or are too busy to cook and eat.
However, some people eat every few hours lest they hit starvation mode or lose muscle. Others’ bodies are well equipped to handle long periods of famine and can miss one or two meals from time to time. You know yourself best.
So, if you’re not hungry one day, skip breakfast and just eat a healthy lunch and dinner. Or, if you’re traveling somewhere and can’t find anything you want to eat, you may be able to do a short fast.
Skipping one or two meals when you feel inclined to do so is a spontaneous intermittent fast.
Just make sure to eat healthy, balanced meals during the non-fasting periods.
Summary: Another way to do intermittent fasting is to simply skip one or two meals when you don’t feel hungry or don’t have time to eat.
Intermittent fasting is a weight-loss tool that works for some people. It doesn’t work for everyone.
It’s not recommended for people who have or are prone to eating disorders. It could also be a potential issue for those with underlying health conditions.
If you decide to try intermittent fasting, keep in mind that diet quality is crucial. It’s not possible to binge on ultra-processed foods during the eating periods and expect to manage your weight and boost your health.
Furthermore, before embarking on an intermittent fast, you should consult a healthcare professional.Last updated on February 17, 2022, and last reviewed by an expert on November 14, 2021.