How Many Hours Should You Fast For Intermittent Fasting

Why Is Intermittent Fasting On Keto Recommended

Intermittent fasting is a technique that involves restricting your food intake to a certain time window each day and then fasting for a specific period. There are several different fasting methods, with many variations that can fit nearly any personal preference or routine. A few of the most common types of intermittent fasting include alternate day fasting, 16/8 fasting and the 5:2 diet, each of which varies based on the amount of time you spend fasting during the week.

Fasting on keto can be incredibly beneficial, especially if youve reached a plateau and arent seeing results from the ketogenic diet alone. While its not required, keto intermittent fasting can bring the benefits of your diet to the next level and help optimize your health. It is also thought to speed up ketosis by helping your body burn through glycogen stores more quickly, which can help sidestep symptoms of the keto flu to get faster results.

There are plenty of keto and intermittent fasting success stories out there, and several reasons you may want to consider adding it to your routine. In particular, keto fasting has been associated with several benefits, including:

What Are The Best Hours To Eat During Intermittent Fasting

To get started, begin by picking an eight-hour window and limit your food intake to that time span. Many people prefer to eat between noon and 8 p.m., as this means youll only need to fast overnight and skip breakfast but can still eat a balanced lunch and dinner, along with a few snacks throughout the day.

Isnt It Important To Have Breakfast Every Morning

Not necessarily. This appears to be an old misconception, based on speculation and statistics, and it does not hold up when its tested.57 Skipping your morning meal gives your body more time to burn fat for energy. Since hunger is lowest in the morning, it may be easiest to skip it and break your fast later in the day.58

Learn more:

You May Like: Is 119 High For Fasting Blood Sugar

Intermittent Fasting 14/: Can It Help You Lose Weight

Medically Reviewed by Dr Babar Shahzad, BSc and MBBS on January 5, 2020.

Intermittent fasting 14:10 requires you to fast for 14 hours and eat all your calories within 10 hours each day.

Intermittent fasting is an increasingly popular eating pattern. It has shown promising weight loss results in both animal and human studies. Besides, IF can lower inflammation, improve insulin sensitivity, and reduce the blood levels of certain fats.

There are many ways to do intermittent fasting. These include the 5:2 diet, 16:8 method, 20-hour fasts, 24-hour fasts, and alternate-day fasting .

Among these, the 16:8 method and ADF have gained widespread popularity in recent years. The majority of scientific studies have used either of these methods more than any other types of IF.

This article takes a closer look at the weight loss benefits of the lesser-known 14/10 method, based on evidence.

Is It Ok To Skip Breakfast

Yes, Varady said. The notion that omitting a morning meal is bad for your waistline likely began with studies sponsored by cereal companies, and most of that research looked at the effects of breakfast skipping on cognition in children, she noted: Im not sure how that all got translated to body weight.

Don’t Miss: Can You Drink Alcohol While Intermittent Fasting

Intermittent Fasting Decreases Metabolism Less Than Continuous Calorie Restriction

When you lose weight, your metabolic rate goes down. Part of this is because losing weight causes muscle loss, and muscle tissue burns calories around the clock.

However, the decrease in metabolic rate seen with weight loss cant always be explained by the loss of muscle mass alone .

Severe calorie restriction over a long period can cause your metabolic rate to drop, as your body enters so-called starvation mode. The scientific term for this is adaptive thermogenesis.

Your body does this to conserve energy as a natural defense against starvation .

This has been demonstrated dramatically in a study of people who lost large amounts of weight while participating in The Biggest Loser, a reality show on TV.

Participants followed a calorie-restricted diet and intense exercise regimen to lose large amounts of weight .

The study found that 6 years later, most of them had regained nearly all of the weight they had lost. However, their metabolic rates had not gone back up and remained around 500 calories lower than you would expect for their body size.

Other studies investigating the effects of calorie restriction on weight loss have found similar results. The drop in metabolism due to weight loss can amount to hundreds of calories per day (

Frequently Asked Questions Concerns And Complaints

Im a woman. Should I do anything differently?

I havent worked with women on implementing an intermittent fasting schedule, so I cant speak from experience on this one.

That said, I have heard that women may find a wider window of eating to be more favorable when doing daily intermittent fasting. While men will typically fast for 16 hours and then eat for 8 hours, women may find better results by eating for 10 hours and fasting for 14 hours. The best advice I can give anyone, not just women, is to experiment and see what works best for you. Your body will give you signals. Follow what your body responds favorably to.

Also, if youre a female, there is an allfemale page on Facebook that discusses intermittent fasting. Im sure you could find a ton of great answers and support there.

I could never skip breakfast. How do you do it?

I dont. Breakfast foods are my favorite, so I just eat them at 1pm each day.

Also, if you eat a big dinner the night before, I think youll be surprised by how much energy you have in the morning. Most of the worries or concerns that people have about intermittent fasting are due to the fact that they have had it pounded into them by companies that they need to eat breakfast or they need to eat every three hours and so on. The science doesnt support it and neither do my personal experiences.

I thought you were supposed to eat every 3 hours?

Here’s why this was a popular idea for a brief period of time:

Here’s the problem:

Free Bonus:

Don’t Miss: Is Fasting Necessary For Psa Blood Test

And Some Of The Donts Of Intermittent Fasting:

2. Do not add a lot of milk to your coffee. Only use half or teaspoon of milk when having tea or coffee. Milk does contain lactose which is sugar. This could derail the plan. Only use a small amount.

3. Use your fasting period to do stuff. Dont sit idle. Getting busy will stop you thinking about food.

4. Dont keep changing your feeding window if you are on the plan that allows food at certain times. If your eating window is between 12 Noon and 8pm, try and maintain that consistency every time. Its all about teaching your body to adapt to a new way of eating and fasting.

5. Do not go to social events where the place will be awash with food on your fast days. The temptation of having so many food choices and so much food around might be too much for you to resist.

6. On your feed days or eating window as the case may be, you should exercise caution in how much food you consume. Theres no need to stuff your face with so much food in an attempt to compensate for the fast period.

It is not a feast or famine ethos and you should refrain from seeing it as such. Eat sensibly!

Above all, be resilient. Its not as hard as it appears. Start small and build up.

If you like your coffee, you may be also interested in the answer to the question: does coffee break a fast?

Suggested further reading:

When Can I Eat On The 1: 8 Diet

You can pick an 8 hour window to suit your day. So, for example it could be between 10am 6pm or 11am 8pm and so on. Plus, you can still drink tea and coffee outside of those hours too, although because of the benefits of drinking water you are also encouraged to stay as hydrated as possible.

Most people choose to fast through the night, and opt to eat their first meal at about 11am or in the middle of the day.

Tom says, The most common hours adopted for the eating period is 12 till 8pm. The reason for this is because people arent normally that hungry in the morning, you dont want to be consuming too many calories during the evening and this allows us to eat our lunch and dinner as well as a healthy snack.

You May Like: Is 119 High For Fasting Blood Sugar

The Bottom Line Longer Fasting Periods Are Better For Weight Loss

Ultimately, if you truly want to follow an intermittent fasting diet without having to restrict food or count calories, its better to aim for longer fasting periods.

For one, the fat-burning benefits of fasting dont truly ramp up until around the 16-hour mark. And secondly, its also much easier for most people to naturally reduce calories if they have a stricter eating window.

The trick is to find what works for you. During my time spent 16:8 fasting, I found it was enough to naturally reduce calories without trying too hard, and it was a short enough fast that I never felt extremely ravenous.

But if youre looking for something you dont even need to follow every day, a 24 hour fast once or twice per week could be more than enough for many people to naturally reduce calories enough to actually lose weight. If you can make it through fasting occasional 24 hour periods, it may be easier to stick to if you can eat more normally the rest of the time.

Intermittent Fasting For Pre

The one time that intermittent fasting may be able to help professional bodybuilders, is when theyre trying to cut down before a competition. If this is the case, then intermittent fasting can be a useful asset, particularly as it may help with lipolysis and increase your daily energy expenditure.

The major key here is to still get enough protein and calories, which shouldnt be hard if youre consuming good foods, in addition to a good whey protein when needed. In general, you should aim to consume 1 gram of protein per pound of your goal lean body weight.

For a pre-competition cut, the 16/8 intermittent fasting method is the best by far, because it will essentially allow you to do 3 things effectively:

So, if youre a natural professional bodybuilder, doing intermittent fasting may be a great alternative to the conventional 6 meals a day diet that most bodybuilders follow.

Read Also: Do Fasting App Cost

Why You May Not See Results

Although there is research supporting the effectiveness of intermittent fasting, there are many reasons you may not see results. It may sound counter-intuitive, but you may not be eating enough calories during your fasting window. If you severely restrict calories, it can backfire. Sudden under-consumption can lead to metabolic adaptation, a process where your body becomes more efficient at using energy and storing fat which means youll burn less calories. The goal is not to count calories and cut them, its to eat minimally processed, nutritious foods during your eating window until you are full.

If you eat ultra-processed, energy-dense foods during your meals, that could be another reason why youre not getting the results you desire. Fasting can help you burn fat, but it doesnt mean that its magic! Remember to fill your plate with lean proteins, complex carbs, and healthy fats.

Finally, make sure you drink plenty of water during your fasting window. Hydration helps you feel full and satiated, and its easy to mistake thirst for hunger. If youre not hydrated when you approach your eating window, you may be prone to choose and eat ultra-processed foods.

What Are The Possible Side Effects

There can be a number of possible side effects of intermittent fasting.40 Heres what to do if you encounter them:

• Hunger is the most common side effect of intermittent fasting. This may be less of an issue if youre already on a keto or low-carb, higher-fat diet.41Learn more
• Constipation is common. Less going in means less going out. However, keep in mind this is a normal response to eating less. It is not a concern and shouldnt require treatment unless you experience significant bloating or abdominal discomfort. Standard laxatives or magnesium supplements can be used, if needed.
• Headaches are common and tend to disappear after the first few times on fasts.42 Taking some extra salt often helps mitigate such headaches.43
• Mineral water may help if your stomach tends to gurgle.
• Other possible side effects include dizziness, heartburn and muscle cramps. Learn more

A more serious side effect is the refeeding syndrome. Fortunately, this is rare and generally only happens with extended fasts when one is undernourished.44

Since most of these side effects are manageable, they do not mean you have to stop your fast. However, if you truly feel unwell, are excessively dizzy, profoundly weak or have other severe symptoms, then you should break your fast.

Just remember to go slowly when you break it and prioritize fluids and salt . And of course, if the symptoms persist, see your doctor immediately.

Don’t Miss: Should You Fast For An A1c Blood Test

You Become Prettier Slimmer And Stronger

The effects of fasting on hormones are multi-faceted. Fasting has a dramatic impact on human growth hormone levels . Increased GH results in greater endurance with faster muscle repair and growth as well as a slowing of the aging process. One study showed that interval training while fasting increased GH by 1300% in women and 2000% in men.

GH is known to create physiological changes in metabolism to favour fat burning and protein sparing. The proteins and amino acids are utilized to repair tissue collagen, which improves the functionality and strength of muscles, tendons, ligaments, and bones. GH also improves skin function, reduces wrinkles & heals cuts and burns faster

The Secret To Intermittent Fasting For Women

By Amy Shah, MD

May 22, 2016

• Crescendo Fasting for Women

Chances are if you are health and fitness savvy, youve heard of intermittent fasting and its benefits for fat loss and overall health.

But did you know that, if youre a woman, fasting could lead to hormonal imbalance and could lead to fertility issues if not done properly? Here, well discuss the best ways for women to enjoy the positive aspects of intermittent fasting without putting their health at risk.

Read Also: What Is 14 10 Intermittent Fasting

Women And Intermittent Fasting

Intermittent fasting can cause hormonal imbalance in women if its not done correctly . Women are extremely sensitive to signals of starvation, and if the body senses that it is being starved, it will ramp up production of the hunger hormones leptin and ghrelin.

So when women experience insatiable hunger after under-eating, they are actually experiencing the increased production of these hormones. Its the female bodys way of protecting a potential fetus even when a woman is not pregnant.

So women have to set cunningly about it. And if you do so, you can get all the benefits of fasting.

One study of healthy young women found that a 10-hour eating window had an anti-stress effect, lowering cortisol and increasing parasympathetic* activity .

*) The parasympathetic nervous system is the “brake” that causes the body to calm down, and which is active when we relax, sleep, eat and meditate.

So if you are a woman or trying fasting for the first time, you might benefit from modified or crescendo intermittent fasting.

This is a more gentle approach that helps the body more easily adapt to fasting. Not all women need crescendo fasting, but it will ensure success in most.

How Long Should You Fast

A common question that I get all the time is, If fasting is so wonderful, how long should I be doing it?

To start with, the first question you want to ask yourself is, what benefit are you trying to achieve with fasting. I have identified that there are 7 different types of fasts, and they all have slightly different benefits to them.

If you are not familiar with the 7 different types of fast, please reference youtube video: for background on how to do all 7 of these fasts.

Recommended Reading: Is 119 High For Fasting Blood Sugar

Can I Exercise During Fasting

Yes. You can continue all your usual activities, including exercise, while fasting.37 You do not need to eat before exercising to provide energy.38 Instead, your body can burn stored energy for fuel.

However, for long-duration aerobic exercise, eating before exercise may increase performance.39 Its also important to drink fluids and replenish sodium around exercise when fasting. This is good to know if youre competing. Learn more

Your Body Will Adapt Give Your Body Time To Acclimate

When are you first starting out, you may experience some hunger pains. This is because you taught your body that you are going to feed it first thing in the morning. If you extend intermittent fasting by 20-30 minutes a day, within a few weeks you can extend your fasting period from 8-9 hours to the 12 hour fasting window.

Same things happens in the evening. Perhaps you have taught your body that when you sit down to relax after dinner, you like to have something sweet to eat. By reducing this back by 20-30 minutes a day, you can optimize your 12 hour intermittent fasting window.

Also Check: How Do I Unsubscribe From Dofasting