Are you looking to improve your overall health and wellbeing? Maybe you’re trying to lose weight, gain more energy, or even extend your lifespan. If so, you’re in luck!
Intermittent fasting is a powerful tool that can help you achieve all of these goals and more. By following the easy-to-understand guide that we’ve put together for you, you’ll learn everything you need to know about this exciting and effective nutrition protocol.
From the benefits of fasting to the best ways to implement it into your daily routine, we’ve got you covered.
So why wait? Start your journey towards a healthier, happier you today by diving into our comprehensive guide to intermittent fasting!
Table of Contents
What is Exactly Intermittent Fasting?
The ‘Intermittent Fasting’ is a way of scheduling your food intake between periods of occasional (intermittent) food abstinence (fasting) and eating windows. In recent years intermittent fasting has taken the fitness industry by storm, major credit goes to Martin Berkhan (founder of ‘Lean Gains’ website) who has promoted it as a nutrition protocol which allows to maximise fat loss, preserve lean muscle and even gain strength.
Intermittent fasting is extremely popular among fitness enthusiasts who have a busy lifestyle yet desires to stay fit and lean. But intermittent fasting is nothing new, our ancestors had to inevitably fast for extended periods during hunting and gathering food.
Source: Freepik
Fasting has also been a part of many religions: Hindus calls fasting “Vaasa” and practices it during special days or festivals, to honor their gods, Islam and Judaism have Ramadan and Yom Kippur, when it’s forbidden to eat and drink for a set period, In Catholicism, there are six weeks of fasting before Easter or before Holy Week. Hence, fasting has always been a part of human history, it is just recently researchers have begun to show its benefits for health and fat loss.
Intermittent fasting offers a host of benefits which includes appetite control, cardiovascular function, blood sugar control, increased effectiveness of chemotherapy (by allowing for higher doses more frequently), neuronal plasticity and neurogenesis (by offering protection against neurotoxins). All these things make it extremely tempting to try out and probably makes you wonder why the whole earth is not doing intermittent fasting.
Unfortunately, the majority of benefits associated with intermittent fasting are observed on the animal (rats and monkeys), not human subjects. The studies done on humans are in poor control, where the diet of non-intermittent fasting subjects is not accounted for. And the comparison is being made between subjects who are on intermittent fasting (consuming whole nutritious foods) and non-intermittent fasting subjects (consuming processed foods randomly). This sparks up an important question: ‘Whether it is intermittent fasting or consuming controlled nutritious calories, which is benefiting the health?’
Thus, there is no definitive answer to whether you should or should not incorporate intermittent fasting as a diet strategy, as the research on this is pretty young. It is more like finding your perfect grey.
You Are Already Doing Intermittent Fasting
There are many strategies for doing intermittent fasting (more on it later), but there is one which you have always been doing, it is called ‘sleep’. Yes! When you are asleep at night for hours, unless you are a person who is munching food in his sleep, you are technically fasting and probably reaping many benefits of fasting.
However, the amount of fasting period required to observe notable benefits varies from person to person. An active person might need 14-18 hours of fasting, a sedentary individual might require up to 20-24 hours of fasting.
P.S: Please do not consider it “The More, The Better” and go on for days without eating.
Intermittent Fasting in a Nutshell & Who Should NOT do it!
Essentially intermittent fasting is not eating for several hours (time may vary from 12-36 hours) and then getting all your calories from 2-4 large meals.
Why larger meals? – Because you have a smaller window of eating, you need to eat more calorie-dense meals. This makes intermittent fasting an attractive strategy for binge eaters who like to hog food instead of eating it. And these are the people who should definitely not do intermittent fasting and probably most of the other diets such as.
Keto, Carb-Cycling, etc, these people need to develop healthier nutritional habits first. If you are someone who has a healthy relationship with food, been eating nutritionally dense foods from a while and wishes to explore health and fat-burning benefits of intermittent fasting, you are in the right place.
Fasting does not mean fat loss: Calories still Count
Anecdotally speaking, I have trained numerous clients over the past few years who used to skip breakfast and directly eat in the afternoon after waking up. Technically they were fasting for 12-16 hours yet they were overweight. And after adding breakfast and a structured meal plan, most of them lost weight.
A recently published research done by a team at Oslo University Hospital in Norway compared the effects of intermittent fasting vs traditional caloric restriction for one whole year (one of the most reliable and robust studies on this subject) and found no significant difference between the two, in terms of weight loss and weight maintenance.
Hence, simply fasting won’t generate fat-loss and an array of health benefits, the quality and more importantly the number of calories you are consuming matters.
Major Benefits of Intermittent Fasting
1. Enhanced fat oxidation
Insulin and glucagon are the two hormones which are primarily into play here. Insulin acts as a nutrient transporter delivering nutrients to their targets i.e. amino acids to muscle tissues, free fatty acids to adipose tissues and glucose to mitochondria and liver (for glycogen storage).
Glucagon, on the other hand, is a nutrient extractor, it makes the liver release glucose by breaking down glycogen and forces adipose tissues to oxidise free fatty acids.
In the absence of food for extended hours (as in case of fasting) insulin levels drop down and glucagon levels rise. Once liver glycogen stores are emptied, the body begins to oxidise adipose tissues for energy requirements. This can result in elevated fat oxidation, causing slightly more fat mass reduction especially in the stubborn regions of the body.
2. Better Dietary Adherence
Perhaps the biggest issue with any fat loss diet is the ability to stick with it. On a calorie restricted diet, you are consuming less than your body’s need. And rarely people like to cut off certain foods and eat less than they used to. Intermittent fasting does not limit the types of food you can eat like in case of a Keto or Paleo diet.
Also, since you have a narrow eating window, you get to eat 2-3 big meals which do not make the mind experience the common diet fatigue. Initially, hunger pangs are pretty bad during the morning (after skipping breakfast) and late nights (after consuming an early dinner) but eventually, hormonal homeostasis settles this issue.
3. Greater Muscle Pumps and Growth
As the body is getting food at limited times, it becomes more efficient in nutrient uptake. Insulin sensitivity increases which enhance the amount of glycogen the body can store in muscle tissue, causing greater pumps during the workout (given you are consuming a moderate/high carb meal pre-workout).
Also, the ability to uptake amino acids from the bloodstream increases which may help stimulate more muscle growth.
4. More Focus & Alertness During Fasted State
This is perhaps something anecdotal, some individuals experience a greater level of mental focus and alertness while some do not. One reason could be that digestion as a process consumes a lot of energy and eating a meal rich in carbohydrates releases serotonin which gives a sense of relaxation. In a fasted state these two issues do not arise.
5. You learn the Difference Between Real Hunger & Mental Hunger
One profound benefit of intermittent fasting is that you gain the ability to distinguish between real hunger & mental hunger. Generally, when people experience hunger, it is not true physiological (body) hunger, but rather psychological (mental) hunger. The better you know the difference between the two, the better you are able to sync with your body’s true need. This prevents weight gain in the future without gauging calories all the time.
Other Health Benefits of Intermittent Fasting
Reduced
- Blood lipids levels including triglycerides and LDL cholesterol
- Resting blood pressure via changes in sympathetic/parasympathetic activity.
- Inflammation in the body (including Cytokines, CRP<, IL-6, TNF, BDNF, and more)
- Development of cancer
Increased
- Cellular turnover and repair
- Growth hormone release in the later stage of fast
- Metabolic rate stimulated by epinephrine and norepinephrine release
Improved
- Blood sugar levels by reducing blood glucose and enhancing insulin sensitivity
- Cardiovascular function by offering protection against ischemic injury to the heart
- Chemotherapy effectiveness by allowing for higher doses more frequently
- Neurogenesis and Neuronal plasticity by offering protection against neurotoxins
Pro Tips for a Successful Intermittent Fasting Journey
1. Staying Hydrated
One essential aspect of intermittent fasting is staying hydrated. Dehydration can lead to various adverse effects, including headaches, fatigue, and dizziness. Hence, it is necessary to drink plenty of fluids, especially during fasting periods.
According to a study published in the International Journal of Food Sciences and Nutrition, drinking water during fasting periods can help reduce hunger, increase satiety, and promote weight loss 1
Therefore, it is recommended to drink at least 8-10 glasses of water every day.
2. Incorporating Exercise
Regular exercise is essential for overall health and well-being. When combined with intermittent fasting, it can lead to better results in terms of weight loss and improved body composition.
According to a study published in the Journal of Translational Medicine, exercising during intermittent fasting can lead to increased fat burning, improved glucose tolerance, and reduced inflammation. 2
It is recommended to incorporate both aerobic and resistance training exercises, at least three times a week, into your routine.
3. Listening to Your Body
Intermittent fasting can be challenging, especially during the initial stages. It is essential to listen to your body and understand its limitations. Pushing yourself too hard can lead to adverse effects, including fatigue, dizziness, and headaches.
According to a study published in the Journal of Nutrition and Metabolism, following a flexible intermittent fasting approach that allows for adjustments in meal timing and duration can lead to better adherence and results. 3. It is crucial to identify your body’s signals and make adjustments accordingly.
4. Keeping a Journal
Keeping a journal can be a useful tool for tracking progress and identifying areas for improvement. It can help keep you motivated and accountable during your intermittent fasting journey.
According to a study published in the Journal of Medical Internet Research, keeping a food diary can lead to better adherence and weight loss results. 4
It is recommended to keep a detailed record of your fasting periods, eating windows, meals, and hydration levels in a journal or a mobile app.
Different Strategies To Implement Intermittent Fasting
A) 24 Hour Fast
This is fairly a simple strategy, you eat a balanced caloric deficit diet throughout the week and one day (preferably Sunday) you do not consume any food. For example, let’s say your daily maintenance calories is 2,500 Kcal.
Here are two ways you can distribute your weekly caloric intake:
1. Monday-Saturday: 2200 Calories i.e. 300 calories below maintenance
Sunday: Complete Fasting i.e. 2500 calories below maintenance
This is a great way of creating a larger weekly caloric deficit, in this case, it is ~4300 Calories. [ 300×6 (normal days) + 2500 (fasting day) ]
Another way can be adding a planned ‘Cheat Day’ before the ‘Fasting day’ where you consume whatever you want using ad libitum. The goal is to eat until you are full, not until you overeat and feel sick.
2. Monday-Friday: 2100 Calories i.e, 400 calories below maintenance
Saturday: ‘Cheat Day’ anything & everything under 4000 Calories
Sunday: Complete Fasting i.e. 2500 calories below maintenance
In this case, the weekly caloric deficit is ~ 3000, pretty decent, given you are able to have an entire cheat day once a week.
B) 20:4 Intermittent Fasting
In this protocol you do not have an entire day of fasting, instead, you fast for 20 hours every day and have a 4-hour eating window. This is great for people who have low maintenance calorie requirements or for individuals aiming to get extremely lean consuming very little calories per day, as it allows you to consume 2 large meals in that short eating period.
C) 16:8 intermittent fasting
This is probably the most famous intermittent fasting protocol on the internet popularised by Martin Berkhan, founder of ‘Lean Gains’ website. In this technique, you fast for 16 hours a day, preferably from a night before to afternoon the following day. The simplest way of employing this method of intermittent fasting is to skip breakfast and consume lunch as your first meal of the day.
How Long Should You Fast?
Uptil now we have explored the various types of intermittent fasting, many of us still wonder how long the fast should last or what time is ideal for fasting. Is the 16:8 pattern good or 20:4 one? Let’s find out.
As explained above the basic difference in both the fasting patterns is the duration for which the fasting window would last. So if you are a beginner, you can begin with 16:8 type, as you have to fast for 16 hr and the eating window can stretch for 8 hrs.
Once your body gets accustomed to this pattern, slowly try to reduce the eating window and reach the 20:4 window.Both of them have their added advantage, which one suits you best, depends on your body type, eating pattern and lifestyle. Choose which one works best for you.
Breaking your fast the right way is Important!
When you break your fast, break it with some lemon water or plain water to avoid overeating.The right way to break your fast is to sit down and sip water slowly, swirling it around in your mouth. Do not just gulp it down. Once this is done, opt for fruits, eat one or two or even have a handful of dry fruits. After a gap of about 30 minutes, you can start introducing other foods too. One can also include a protein shake as a first meal, as it will keep you full for longer and help meet your requirements too.
The beauty of intermittent fasting is that practicing it can help reduce your appetite over time. It will help you feed your body the amount, through a steady process and not what your emotional mind craves for.
Summary
Intermittent fasting involves scheduling food intake between periods of fasting and eating windows, and has gained popularity in recent years due to its benefits, including weight loss, increased energy levels, and a potentially longer lifespan.
However, the benefits of intermittent fasting on humans are still being studied and are not yet definitive. One should not aim solely for weight loss with intermittent fasting, as it is a short-term goal and does not address the root cause of excess weight gain. The weight you lose by following this as a shortcut might come back. So, consider incorporating intermittent fasting to address the root cause, modify your lifestyle habits, engage in regular physical activity, manage stress effectively, and regulate your sleep cycle well.
Frequently Asked Questions (FAQs)
Will I lose my gains if I do not eat for so long?
Eating 5-8 meals throughout the day is a commonly accepted norm to stay ‘anabolic’, a state where the body maintains its positive nitrogen balance, preventing muscle breakdown. However, research shows that positive nitrogen balance is a function of total protein intake (precisely amino acids) and not the number of meals you consume a day. Thus, fasting won’t make you lose your gains, given your protein intake is in check.
What can I consume during the fast?
During the fast, only plain water can be consumed. Intake of 4-6 litres is essential to keep your body hydrated. It also tricks your mind by keeping your stomach full, as the pathways for satiation and quenching thirst are the same in the brain.
What if I am not able to do intermittent fasting?
If you decide to try intermittent fasting, do not go the ‘cold turkey’ method and start with a 24-hour fast. Start slowly by adjusting regular mealtimes by an hour, then start fasting 12-14 hours and then gradually try more aggressive approaches. If it works for you ‘Superb!’ If not, do not worry, intermittent fasting is not the end-all, be-all of nutrition or fitness.
Is intermittent fasting a fad?
No, intermittent fasting was never a fad, however over the years it has gotten this reputation because people use it as a shortcut to lose weight. If done correctly it can yield good results in terms of weight loss.
Can people with diabetes practice intermittent fasting?
It is quite difficult to answer this, as the sugar levels can vary and are different for everyone. But if you are someone with Type 2 Diabetes, practice it safely under medical supervision, to avoid any chances of hypoglycemia.
Can people suffering with acidity practice intermittent fasting?
Acidity can be caused by various reasons, maybe overeating or having a large meal gap. However, one shouldn’t give up. One day, you might feel more acidic; on day two, it will settle down a bit and gradually improve. Just believe and try.
What about maintaining meal gaps, isn’t eating every two to three hours healthy?
Let’s break this myth behind this claim of eating every few hours. People with conditions like type 1 diabetes, will need to take their insulin dosage at particular intervals, post which meals or snacks are required. Apart from these special medical conditions, we do not have to eat as much frequently as we are eating today.
Can it help me lose body weight?
Intermittent fasting can definitely help in losing weight as it is a calorie restricted dietary pattern, so when you fast, you enable your body to flush out toxins more effectively, the less the toxins, more the fat burn. But weight loss should be achieved by a sustainable approach, change your lifestyle, address the root cause then only your weight loss can be sustainable.
Is it recommended for breastfeeding moms?
No, as when one is breastfeeding, the body’s nutritional demands are at their peak. Wait until this phase is over before starting intermittent fasting.
Can you drink liquids during intermittent fasting?
You can drink only plain water, either at room temperature or slightly lukewarm. If you wish to drink cold water, have it from clay pots.
Can you exercise during IF?
Exercise is a personal choice, it is best to practice gentle exercises if you are a beginner and starting a workout in the fasting phase.
Why do I experience headaches when intermittent fasting?
It is a very common symptom during intermittent fasting. Acidity, migraine, headaches are common symptoms. In some rare cases, one may experience rash, fever etc. This all is just a sign that your intermittent fasting is successful in getting rid of toxins and waste.
- Mekary, R. A., Rood, J., Ishikawa-Takata, K., Kelly, N. R., & Wojtkiewicz, C. A. (2015). Water consumption and weight loss: The evidence. International Journal of Food Sciences and Nutrition, 66(6), 692-698. doi: 10.3109/09637486.2015.1075900[↩]
- Tinsley, G. M., La Bounty, N. P., & Grandjean, P. W. (2015). The effects of intermittent fasting on body composition and clinical health markers in humans. Nutrition Reviews, 73(10), 661-674. doi: 10.1093/nutrit/nuv041[↩]
- Kroeger, C. M., Trepanowski, J. F., Barnosky, A., Klempel, M. C., Bhutani, S., Hoddy, K. K.,… Varady, K. A. (2019). Flexible vs. fixed: a randomized intermittent fasting trial. Journal of Nutrition and Metabolism, 2019, 1-9. doi: 10.1155/2019/7862650[↩]
- Burke, L. E., Wang, J., & Sevick, M. A. (2011). Self-monitoring in weight loss: a systematic review of the literature. Journal of the American Dietetic Association, 111(1), 92-102. doi: 10.1016/j.jada.2010.10.008[↩]
