Most diets require what to eat, but intermittent fasting focuses more on when you eat. It seems simple enough, but going without food for hours will be challenging, especially for regular eaters.
So, how to survive fasting and cutting down food intake to a set period of time? In this article, you will find the recommended tips for maintaining your health and energy level throughout your fast.
Why Try Intermittent Fasting (IF)?
Intermittent fasting’s basic rule involves cycling between periods of not eating or sharply restricting your food intake for certain periods of time.
Fasting for a certain number of hours each day or eating just one meal a couple of days a week can help your body burn fat. There are also several scientific evidence pointing to some health benefits of intermittent fasting.
However, fasting can be risky if not done properly. Intermittent fasting may benefit for health and weight management, but it is only suitable for some.
Intermittent Fasting Types
1. Time-Restricted Eating (16/8 or 14/10 Method)
A time-restricted fast means you have set fasting and eating windows. For example, you fast for 16 hours of the day and can only eat for the rest of the eight hours remaining.
Most try to have a portion of their 16-hour fast overnight. Since you are already fasting while asleep, this method is particularly popular and generally easier to adapt. It’s especially convenient as you extend your overnight fast by skipping breakfast and not eating until lunch.
This form of fasting is a safer bet for if you are interested in trying intermittent fasting for the first time.
Some of the most common ways are:
- The 16/8 method.
- The 14/10 method.
This method of intermittent fasting can be repeated as often as you’d like or even done once or twice a week — whatever your personal preference is. Others who have adjusted quite well to fasting even do this type of fast daily.
Finding the right eating and fasting windows for this method might take a few days to figure out, especially if you’re very active or if you are used to having breakfast.
2. The Twice-A-Week Method (5:2 Method)
In this method, you can consume about 500-600 calories on two non-consecutive days of the week. You then eat normally, preferably on a healthy and normal diet, for the other five days.
During your fasting days, this approach usually includes a 200-calorie meal and a 300-calorie meal. It’s essential to focus on high-fiber and high-protein foods to help fill you up and keep calories low when fasting.
You can choose whichever two fasting days you want as long as there is a non-fasting day between them.
Its name pretty much explains what it is. Alternate day fasting (ADF) is a type of intermittent fasting involving switching between fasting days and non-fasting days, referred to as eating or feeding days.
You can take one of two approaches:
- You can fast completely on fasting days, consuming only water, or
- You can eat small meals up to 20–25% of your regular caloric intake.
The 20–25% requirement is a variation that involves “modified” fasting. During this fasting schedule, you usually alternate four days of calorie restriction with 500 for women and 600 for men, then eating freely for three days.
Alternate-day fasting is considered one of the most extreme forms of intermittent fasting, and it can be tough for some of you to follow. If you choose to eat nothing at all on your fasting days, start by limiting your fasts to no more than two days per week.
4. The 24-Hour Fast (Eat-Stop-Eat Method)
This method involves fasting completely for a total of 24 hours. However, this is often done only once or twice a week.
Most people fast from breakfast to breakfast or lunch to lunch. With this version of intermittent fasting, the side effects can be extreme, such as fatigue, headaches, irritability, hunger, and low energy.
If you choose to follow this method, you should return to a normal, healthy diet on your non-fasting days.
How Effective Is Intermittent Fasting?
Intermittent fasting has been shown, in many short-term research studies, that it can help you lose weight, improve your health and potentially protect you from developing certain diseases.
What you may find most appealing is that it doesn’t restrict you daily, like conventional dieting. Even with fewer restrictions, it’s easy to understand how IF works for weight loss.
When you set time limits on your eating, you tend to eat less. This way, you are creating a smaller eating window by restricting calories enough to achieve weight loss.
There is also an occurrence of autophagy during fasting. Autophagy occurs when your body’s cells are deprived of nutrients or oxygen or if they’re damaged in some way. Fasting deprives your body of nutrients, forcing it to repurpose cell components to function1.
While studies are in their early stages, findings2 have suggested that autophagy helps in:
- Weight Loss
- Chronic Disease Prevention
Health Benefits Of Intermittent Fasting
1. Weight Loss
Intermittent fasting is a great tool for weight loss because it targets your body’s fat while maintaining lean muscle. When done appropriately and under medical supervision, fasting has some health benefits that are better than a traditional caloric restriction diet.
A study placed on resistance-trained men on an intermittent fasting diet experienced a significant decrease in fat mass and even maintained some muscle mass3.
IF has also been shown to be a good tool for weight loss for overweight or obese individuals. Researchers who looked at data from 27 studies and found that IF helped participants lose up to 13% of their weight4.
2. Reduced Insulin Resistance
One of the main drivers of fat storage is insulin. Constantly eating triggers insulin production all day long. When you have too much insulin, your cells start to resist the insulin, and, in response, your body has to make more.
Intermittent fasting encourages insulin levels to fall, which may play a role in reducing the risk of type 2 diabetes.
In some studies, fasting was used as a weight-loss intervention and strategy for maintaining a healthy weight. It has shown that people who intermittently fast had lower levels of blood glucose, which was the goal in the prevention and treatment of diabetes5,6.
3. Reduced Blood Pressure
With intermittent fasting being effective in improving insulin resistance, it is not surprising that intermittent fasting also helps to decrease blood pressure.
In fact, a 2018 study found that 16/8 significantly decreased systolic blood pressure in the 23 study participants7.
In another study, one month of alternate-day fasting effectively lowered blood pressure and heart rate in healthy nonobese humans, suggesting that chronic fasting may enhance parasympathetic activity8.
4. Reduced Inflammation
Your body naturally undergoes inflammation as a part of the process it uses to fight off harmful pathogens or recover from injuries by triggering your immune system. However, when inflammation persists for too long, it can start causing you harm.
Inflammation can damage blood vessels and increases the risk of heart attacks and strokes.
Research9 shows that intermittent fasting lowers chronic inflammation without compromising antimicrobial immunity, which is a protective barrier against bacteria, viruses, and fungi.
5. Lower Cholesterol
Your cholesterol might also improve after intermittent fasting, especially when combined with a healthy diet during your non-fasting periods.
In one study, better lipid profiles have been found after intermittent fasting, including lower overall cholesterol, lower LDL (low-density lipoprotein), and lower triglyceride levels in healthy and overweight populations10.
However, further studies are needed to explore the differences in short-term vs long-term metabolic changes associated with fasting.
Intermittent Fasting Challenges
The benefits of fasting generally come from going without food for hours at a time, but it will likely take some adjusting in the beginning.
If you are able to fast safely, the following are some of the few challenges you could encounter when first trying intermittent fasting:
When you’re not used to fasting, hunger is your greatest obstacle. However, starvation is also not the answer.
You’ll want to learn new ways of responding to your hunger signals by changing what you eat, or changing how you react to hunger pangs.
2. Affects your mood.
One of the things you may notice when you first start IF, aside from feeling more hungry, is mood swings. You may experience irritability and other mood disturbances that could affect your fasting period.
3. Goes against your intuition.
Intermittent fasting may require you to go against your intuition and normal routine. It involves planning, discipline, and restraint.
This can be challenging if you’re used to relying on your intuition when you decide to eat, particularly when you get hungry and you’re still in your fasting window.
Not to mention when you’re not used to following a strict schedule, you might find intermittent fasting frustrating.
What Are The Downsides?
Fasting is generally considered safe, but there are some side effects and possible risks involved.
Primarily, it’s the hunger pangs that are expected and are the main side effect of intermittent fasting. You may also feel weak and your brain may not perform as well as you’re used to.
However, all of these are temporary, as it can take time for your body to adapt to the new meal schedule.
Additionally, if you have a medical condition, you should consult your doctor or have medical supervision before trying intermittent fasting.
This is particularly important if you:
- Are underweight.
- Have low blood pressure.
- Have diabetes.
- Have problems with blood sugar regulation.
- Take medications.
- Have a history of eating disorders.
- Are a woman who is trying to conceive.
- Are a woman with a history of amenorrhea.
- Are pregnant or breastfeeding.
Planning Your Fast
If you are a first-timer, practicing intermittent fasting may be difficult for you mainly because you have to eat during a short window of time each day or alternate between days of eating and not eating.
The best way to begin fasting includes identifying your personal goals, planning your meals, and establishing your calorie needs. This way, whether your goal is to lose weight or for your health, you have set up a clear plan to help you survive your first few hours of fasting and eventually get you to fast a little longer.
How To Survive Fasting
Make sure you’re ready for a long-term commitment and be really clear as to why you want to fast in the first place. Your reasons for fasting could be for health or for losing weight, but it will take some time to receive the full benefits of IF.
As for long-term weight loss, it takes time and effort. This is why you should ensure you’re ready to make permanent changes to your eating schedule while also making lifestyle changes, such as turning to a healthier diet and forming healthy activity habits.
Making these changes prevents you from negating all the benefits intermittent fasting offers. Your fasting success relies on your total commitment even after receiving the results.
2. Start slowly.
You don’t have to start with such a long fasting window. You can start with a 12-hour fast. Gradually increase the length of your fast an hour at a time until you reach the 16-hour mark.
In addition, don’t feel as though you have to start fasting every day. Try starting your fast on the weekend. This will help you dip your toe into the fasting lifestyle without feeling overwhelmed.
3. Choose the right schedule.
There’s no specific time with IF that you should follow, and as long as you have adjusted and eventually get near the 16-hour window, that is okay. Find the right time that works for you.
You may find it more difficult to fast when you’re idle, and an option is to choose to have your fast while sleeping. This means choosing the window to eat within hours before going to bed.
4. Cut down on activity.
If you aren’t used to fasting, it’s a good idea to limit your activities during your fasting windows until you know how your body will react. While fasting should not hinder you from doing any activity at all, when you are still new to it, you may struggle with feelings of fatigue or weakness.
Additionally, if you’re not planning to replenish nutrients for a while, preserve your energy for vital daily activities.
5. Stay busy.
Distract yourself and keep your mind occupied. Stay busy, and avoid the kitchen or any place that would tempt you to break your fast.
Keeping yourself busy while you wait for the time you can start eating makes struggling with hunger pangs less of a struggle. If you sit and do nothing while waiting, it will start to feel like time is going by much slower.
By keeping your mind busy, the time to eat will arrive before you know it, and you may even forget about the fact that you have not eaten yet. If possible, schedule your activities during your fast and make it a productive fasting period.
6. Stay hydrated.
During your fasting windows, you can and should still drink water. It is completely calorie-free, so it will not break your fast.
Staying hydrated also helps when you’re fasting. It tricks your brain into believing you’re full even if you’re not. There are even times when you might think that you’re hungry when you’re really just thirsty. Water will keep you going until it’s time for you to eat.
7. Find someone to do it with.
There will be days when IF will be extra tough for you, which can make it easy to fall back into old habits. Going through this process alone could be challenging. You might give up if no one is pushing you to do better.
It will be easier when you have someone to do it with, so a strong support system can make all the difference. Try it with a friend, family member, or even your spouse.
You can share your struggles, and thoughts, or even just motivate each other. You might also inspire them to push forward if they consider giving up. You can be each other’s support system. You can also celebrate your success together.
8. Find what works for you.
Depending on your sleeping schedule, you may want to experiment with how often and when you eat to keep your energy up. Find a plan that works with your schedule and lifestyle, a plan you can sustain, especially if IF is something you want to do for the long term.
Everyone has a different metabolism and goals so don’t be afraid to use trial and error to see what works best for you and your body. This may take a little time, so be flexible and open to trying different fasting and eating windows.
9. Trust how your body feels.
It is necessary to listen to your body and be mindful of it to determine your health.
Symptoms like weakness or fatigue, irritation, anxiety, dizziness, and lack of concentration indicate that your body is undernourished and starved. These are usual at the beginning of intermittent fasting.
While it is natural for your body to react to the changes of fasting, it is recommended to keep monitoring yourself and give the fasting schedule roughly a week to adjust to normalcy.
However, suppose such symptoms persist for longer. Then, it is highly advisable to modify your fasting schedule accordingly or even discontinue and opt for other means to lose weight.
10. Surviving fasting long term.
Intermittent fasting is a lifestyle strategy that can be used long-term when done properly. If you at a point you have anything that disrupts your fasting routine, such as an event, illness or even lose motivation, just take a little break and return to eating your regular diet every day until you’re ready to get back into your fasting regime again.
What To Eat
It is generally recommended to consume high-protein and high-fiber foods during your non-fasting cycle. High-protein and high-fiber give you energy for longer because they take longer to be digested and absorbed in your body.
Consuming too much sugar and other simple carbs, such as white bread, will cause your blood sugar to spike, and then you’ll crash and feel hungrier.
Water may be your go-to drink to aid your fasting but there are other drinks you can consume, especially for extended fasts. These are:
Effects On Exercise
Intermittent fasting while exercising is healthy, safe, and can help you reach weight loss goals faster. Exercising in a fasted state has some pros and cons over exercising in a fed state. Fasted training can help to burn more fat.
If you are a healthy individual, IF should not affect your ability to exercise, except during the period when your body is adjusting to the new eating schedule. After the initial adjustment period, you should not experience any negative effects on your exercise routine due to fasting.
If you are worried about losing muscle while fasting, this can be remedied by consuming enough protein during eating periods and also by engaging in resistance training regularly. By keeping your protein intake up, you are less likely to lose muscle mass from fasting.
The important thing is to remember that you have a choice, and it is not necessary to exercise while fasting. Exercising during your eating window is very much acceptable. In the end, you have to find out for yourself what works best for you.
When done healthily, fasting provides numerous benefits not just limited to reductions in body fat but for your health too. Whatever your reason for wanting to intermittent fast, you should also be aware of some less-than-appealing side effects.
You may feel tired, get a headache, and generally feel queasy in your first few days, but that’s normal. Remember that it can take several weeks to get used to, but you will eventually adjust with the help of the fasting tips mentioned above.
Also, bear in mind that even if you follow all these best practices, intermittent fasting may have different effects on different people. If you plan to make fasting a part of your routine, talk with a medical provider about any possible risks.
2 Welch, A. (2022, December 9). The Ultimate Guide to Autophagy: What It Is, Why It Matters, and How It Impacts Health. Everyday Health. https://www.everydayhealth.com/diet-nutrition/autophagy-what-it-is-why-it-matters-and-how-it-impacts-health/#potential-health-benefits
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