- For the 16: 8 intermittent fasting method, eating an early dinner and skipping breakfast may be the easiest way to stick to the schedule.
- If you are using the 2:10 pm method, you can start fasting at 7:00 pm or 8:00 pm to digest dinner before going to bed.
- If you prefer the 5: 2 method, make sure you don’t fast for two consecutive days.
- Visit the Insider Health Reference Library for more advice.
Intermittent fasting is an eating plan that allows you to alternate between eating and fasting according to a schedule. It is usually used by people who are trying to lose weight or lead a healthier lifestyle.
“Intermittent fasting has gained popularity because scientists have found that when animals are given a very low-calorie diet, they live longer and are healthier. But eating a very low-calorie diet is not realistic for humans, so fasting was the next best thing, “says Michael Crupain, MD, medical director at Sharecare, a digital health company.
For people unfamiliar with this eating plan, the prospect of fasting may seem daunting. Fortunately, there are many scheduling options to choose from.
Here are all the different ways to fast intermittently to help you decide which option is best for you.
Method 16: 8
A 16: 8 intermittent fasting program still has 8 hours where you can eat every day.
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The 16: 8 method involves fasting for 16 hours every day and eating only for an 8-hour window. You can have your three regular meals during those 8 hours.
Be careful not to eat more food than you would normally eat outside of fasting hours. Eating too much during 8 hours in anticipation of the 16-hour fast will be counterintuitive to your goals.
And just keep in mind that while this is one of the most popular methods of intermittent fasting, some research has cast doubt on its effectiveness for weight loss.
The best time to fast: This is a commonly preferred method of intermittent fasting because most of your fasting period usually happens when you are sleeping.
For most people using this method, having an early dinner and skipping breakfast can be the most effective way to stick to the schedule. Let’s say you finished dinner at 8pm, your next meal will be an early lunch at 12pm. You can drink water or other drinks with no calories while fasting.
Method 14:10
A 14:10 intermittent fasting program has 14 hours of fasting per day.
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The 14:10 method is an alternative to the 16: 8 method for people who may find it difficult to fast for 16 hours. In that case, you would fast for 14 hours and eat your meals for a period of 10 hours.
As with the 16: 8 method, you can also drink water or other non-calorie drinks while fasting.
The best time to fast: Although people usually start fasting at 7 pm or 8 pm, you can start later or sooner. However, starting fasting at 7 or 8 pm is ideal because you usually eat your last meal a few hours before bed, which gives your body time to properly digest food before bed.
Method 5: 2
An intermittent 5: 2 fast schedule includes two full days of fasting.
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With the 5: 2 method, you must restrict the number of calories you consume for two days a week. During the other five days, you can eat normally. On fasting days, it is generally recommended that you eat no more than 400 to 500 calories.
The best time to fast: When using the 5: 2 method, you should avoid fasting for two consecutive days. Fasting for two consecutive days makes you more susceptible to side effects such as extreme hunger, irritability and fatigue.
Fasting every other day
An alternate day fasting program is difficult and not always recommended.
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As the name suggests, fasting on alternate days requires you to fast on alternate days. Some people do 24-hour fasts, but this can be overwhelming for those just starting out. Alternatively, you can restrict your usual calorie intake on fasting days, so that you feel comfortable.
Fasting on alternate days has become more popular in recent years, but medical experts warn of its potential health risks.
In a small 2017 study, researchers divided 100 obese women into three groups. The first group followed an alternate fasting diet that allowed them to eat 25% of the calories they needed on fasting days and 125% on non-fasting days. The second group restricted their calorie intake to 75% every day, and the last group ate normally.
At the end of the one-year study, the researchers noted that women in the first two groups had lost about 5.5% of body weight by the sixth month of the study.
However, those who alternated fasting also had significantly higher levels of low-density lipoprotein (LDL) cholesterol than those who restricted their daily calories – indicating an increased risk of dangerous heart disease, such as heart attacks and strokes.
So it is best to consult your doctor before alternating fasting.
The best time to fast: For people who do 24-hour fasts, you may want to take advantage of starting the fast right after dinner. If you start a 24-hour fast at 7 pm and go to bed from 8 to 9 am at 10 pm, there will only be 12 to 13 hours left in your fast when you wake up.
However, this method is generally not recommended, so proceed with caution.
Eat-stop-eat
This method involves fasting for 24 hours, once or twice a week. This means that if you have dinner at 8pm on a Wednesday, your next meal will be at 8pm on Thursday.
The biggest drawback to this method is that many people find 24-hour fasts difficult to endure. This method may also not be safe for people with certain medical conditions, such as diabetes or an eating disorder.
You are allowed to drink water and drinks without calories during periods of fasting. This can help you deal with the feeling of hunger. For people who fast for 24 hours, you may experience side effects such as headaches, fatigue and irritability.
The best time to fast: With the eat-stop-eat method, you can fast any day of the week you choose. However, if you fast twice a week, it is advisable to choose two non-consecutive days.
Skip spontaneous meal
Not all intermittent fasting schedules follow a rigid time frame. With spontaneous skipping meals, you can simply skip a meal you don’t need to eat every now and then. For example, if you had a big lunch, you may decide to skip dinner.
This method is especially great for beginners who are not sure which intermittent program will work best for them. While flexibility may be the greatest advantage of this method, it is also its disadvantage.
“Skipping spontaneous meals can help reduce calories, but you’re likely to overeat later. Following a structured diet and fasting schedule is important to help you stay consistent and develop the habits necessary to succeed in intermittent fasting,” said Crupain.
Insider Takeaway
Starting an intermittent fast meal plan can seem daunting. Fortunately, there are many different schedules where you can try to find the best plan for you.
Intermittent fasting is a risky eating plan for many. People who are pregnant, have had eating disorders, medical conditions like diabetes and people aged 65 and over should avoid intermittent fasting.
In general, if you are considering an intermittent fasting schedule, you should talk to your doctor first to make sure it is the right diet plan for you.