Check out one of my favorite "done for you" fasting options: the Prolon system
In this article you will learn:
The different kinds of fasts and how to implement them
What the research says about IF and PF (intermittent and periodic fasting)
Some simple, but powerful tips to incorporate fasting into your life
Lazy Reader's Section:
Fasting is a powerful tool in your arsenal for good gut health and insulin balance, as well as spiritual and mental clarity, but it must be done with planning and consideration - as well as a clear intent. If you are new to fasting, a "done for you" 5 day program that works is the Prolon system by longevity author Dr. Valter Longo.
Lazy Author Alert:
Some research is cited at the end of this article for further reading, but if you want the full gory details then grab yourself a copy of my book, Dance Your Way Through Life: A No Bullshit Guide to Hacking Your Body, Mind & Soul for Success.
Fasting is a timeless practice that has been around since as long as we could write. We also evolved in constant scarcity, with intermittent periods of fasting being the norm that our bodies had to get used to. In fact, this is one simple reason why obesity is so prevalent in adults, kids and even pets - our bodies aren't used to the sheer amount of surplus constantly available.
Today this ancient practice has become super sexy thanks to many health entrepreneurs and celebrities, and while there are many benefits to fasting regularly - my goal with this article is to help you push the hype aside and really be true to yourself. Fasting is powerful, but it's not something you should do just because it's the latest thing since sliced bread. To understand a bit more about fasting in general, let's break down a few things:
What is Intermittent Fasting?
Intermittent fasting is a broad term for fasting done intermittently or periodically. This is either in the form of a dedicated eating window every day or occasional fasts periodically throughout the week, month or year. You have probably seen terms like “16:8” or “5:2” – these are just references to the type of intermittent fasting being done. 16:8 means 16 hours of fasting with an 8 hour eating window, while 5:2 refers to a week where you fast 2 days and eat 5.
The Different Types of Fasts
Fasting is a beautiful practice because it is very broad. You can fast from spending, from technology, from sex or from people. It’s not just about food, and even in that category there’s many ways to incorporate fasting into your daily routine:
Weekly/Periodic Fasts – This is where you choose to fast (just water) for a given amount of time. This can be a day, two days or more. Some people choose to fast on one or two days of the week, or do periodic fasts every 3-6 months of 1, 2 or more days. Be mindful that anything more than 2 days in a row requires medical supervision, training and careful planning.
Daily Window Fasting – This is the more popular understanding of “intermittent fasting,” but can also vary greatly because the eating window is up to you. Some people eat all of their food in a 6 hour window, like from 12pm to 6pm, or a 10 hour window, like from 10am to 8pm. The window is up to you and your particular lifestyle – the key is making it sustainable.
Reduced Calorie/Fasting Mimicking – Calorie restriction (CR) is a similar practice to fasting, although different in some ways. The work of Dr. Valter Longo in his book “The Longevity Diet” details the impact of short-term calorie restriction as a means to mimic the benefits of fasting. In this book he also details the impact of 2-3 days of water fasting as a protective mechanism against chemotherapy and its benefits in non-clinical settings. I highly recommend the book, and the research Dr. Longo discusses was also used to create the popular "done for you" 5 day fasting-mimicking program, Prolon. Give it a try because it works.
Protein/Carb Fasts – Similar to the above, a protein/carb fast is where you drastically reduce protein or carbs for a day for gaining some of the benefits of fasting (see below) like insulin resistance improvement.
Probably more important than understanding the different types of fasts is why you are fasting in the first place. Too many people jump into this ancient practice (now a fad oddly enough) without the proper “why” guiding them and their decisions, which can lead to more harm than good. Below are some of the main reasons why you would take fasting on as a practice, each with different outcomes in terms of your actions and how much fasting you end up doing:
1. Regulate circadian rhythm. With eating-window type intermittent fasting (i.e. choosing when you eat and don’t eat every day), one is able to promote a regular circadian rhythm. What you put into your body and when you put it in programs how you feel throughout the day, and choosing when to eat and not to eat allows for a regular circadian rhythm which is central to a balanced nervous system, stress levels and long-term health.
2. Regulate blood sugar. Another powerful benefit of fasting in all of its forms, although especially the daily intermittent eating window fasting, is the ability to regular blood sugar. Regular periods of fasting for at least 1 day (24 hours) have a positive effect on insulin resistance and intermittent fasting can help your body by giving the pancreas a break from working constantly. This, of course, also assumes you aren’t eating garbage during your eating window as well.
3. Manage weight. Similar to the above, regular periods of fasting or intermittent fasting help to promote weight loss, burn fat through ketosis and overall manage your intake of food. Remember that what you eat as well as when you eat it can make a big difference in your waist line – so restricting your eating window and promoting a healthy circadian rhythm (sorry, no more ice cream late at night) can promote and maintain a healthy weight.
4. Heal the digestive tract. Your colon(s) take a beating from all the stuff that goes through them all day. Not to mention most people have some form of “leak gut” these days and chronic inflammation from the foods they eat, an imbalance of intestinal flora and parasites, fungi, etc. causing havoc. Fasting, especially if for at least 24-48 hours, can allow the colon to heal and flora to rebalance. It is a great way to reset yourself and allow the body to regenerate.
5. Promote longevity. Fasting as a “longevity hack” has become very popular today but why exactly it is useful is less understood by the masses. Fasting creates discipline, manages your blood sugar and weight and gives the body time to reset using processes like autophagy (recycling old or damaged cells). Each of these benefits are important, but they are achieved at different thresholds so this is why it is important to know why you are fasting in the first place. In general, taking a break from eating all the time through an eating window will promote your longevity for a variety of reasons because over time your body just isn't in a constant effort to digest food. But if you really want to reap the rewards of autophagy and insulin resistance, then periodic fasts of 24-72 hours every 3-6 months are going to add to your clock because the magic starts to happen after a full day of not eating. No free lunch in life, right?
6. Develop spiritually. This final reason is, in my opinion, the most important. Fasting has been one of the most time honored practices for developing discipline, focus, appreciation and spirituality. In this realm, fasts can be as long as a week or more (remember, anything over 2 days requires supervision and training) and can reveal many things about ourselves. Fasting is also a powerful tool to get present and discipline the mind, detach from dependence on substances (food is a substance) and develop mindfulness, sensitivity and awareness where life has left us desensitized. Fasting uses the power of absence and space to create a unique experience of learning and discovery available nowhere else, and this is a perfect complement to our achievement driven modern lives.
How to Practice Intermittent Fasting
Below is a basic guide to begin practicing intermittent fasting in your routine. Remember to do your own research, start slow and always opt for what’s sustainable over what’s popular.
1. Pick an eating window that’s reasonable for your schedule. You can start with 12 hours and then work your way up to 8, 9 or 10 with 1 hour less each week. I personally try to float around 9-10 hours most days, but as long as you are giving your body a break from food for at least 12 hours, you’re going to reap some rewards.
2. Adjust your carb intake. One popular diet that incorporates intermittent fasting is the “keto” diet. Again, do your own research, but a good principle to shoot for is less carbs and more good quality fats (olive oil, grass fed butter or ghee, etc.). High carb meals spike your insulin, which causes it to crash later (you get hungry suddenly and stay less satiated) while also contributing to stress on your pancreas and leading to insulin resistance down the road. Instead, fats keep you satiated and hunger doesn’t creep in suddenly anymore. Changing your ratio of carbs to fats will help with intermittent fasting because you won’t suffer crashes outside your eating window that will force you to cheat.
3. Eat better in general. Along with the above advice, drop the sugar and fried food from your diet and replace it with good quality fats, lean organic/grass fed proteins and less but still high quality carbs (rice, squash, etc.) with a base of organic vegetables. Remember that it’s all about sustainability and evening out your blood sugar response with intermittent fasting, so cleaning up your diet is a necessary part of your practice. For all the wonderful details and principles around creating a healthful diet (not dieting), grab yourself a copy of my book, Dance Your Way Through Life: A No Bullshit Guide to Hacking Your Body, Mind & Soul for Success and remember: an eating window is pointless if you are eating Cheetos and McDonald’s for 8 hours of the day.
4. Extend your fast in the morning with a buttery drink. The popular “Bulletproof Coffee” or “keto coffee” drink of coffee, grass fed butter and MCT oil has caught on as a morning “hack” to extend one’s intermittent fast. This is done because fat makes you feel full, but doesn’t spike your insulin like sugar (carbs) or protein. In essence, your body is fooled into being full, but is still in a fasting state from a blood sugar perspective.
This is a useful tool in your arsenal, although there’s a few considerations:
If you metabolize caffeine slowly (check your genes like COMT), suffer from adrenal fatigue or are sensitive to coffee then this may need to be replaced with something else. I recommend golden milk (turmeric) or non-caffeinated tea like Rooibos tea. Remember that coffee, no matter how touted it is for its benefits, still induces a stress response in your body. Notice how you feel, always get a reputable source and listen to your body.
If you are dairy (casein) intolerant, you may try Ghee or coconut oil. Do not use olive oil or any other fats besides saturated fats because they will denature in the heat (plus it won’t taste good either).
MCT oil raises your ketones and helps to give a fat-burning boost to your morning, but too much of it can cause diarrhea. Also, while the boast of this oil is that it curbs appetite, there are studies that show it increases ghrelin (your hunger hormone) and stimulates a substance in your body responsible for appetite called Neuropeptide Y. What this all means is that MCT oil can increase your hunger, so be mindful. A final warning with MCT oil is to be aware of your VDR gene. This can be done through a testing service like SelfDecode. MCT oil is rapidly absorbed into the body and, if you take a vitamin D supplement (fat soluble) the MCT oil can upregulate the vitamin D. Depending on your VDR gene and how you process vitamin D (if you uptake it quickly), taking MCT oil and Vitamin D together can result in heart palpitations.
Some Useful Considerations for Your Fasting Practice
Everybody’s body is different, and fasting is not a “one size fits all” type of box. Neither is the “keto” diet, Bulletproof coffee or any other modern fad. You must do your research and know yourself inside and out to fully maximize any of these practices. Below are some suggestions that I’ve found useful in creating my own practice:
1. Find a functional medicine doctor you trust. Everything is interdependent with everything else. Fasting as a practice involves a look at your diet, your own biology, stress levels, schedule, response to fats and a variety of other considerations. You should always do your research and be your own doctor, but having a great functional medicine doctor by your side will help tailor and customize the lifestyle that is best for you with these tools. A functional medicine doctor is a doctor that utilizes new techniques, thinking and protocols to look at the body as a whole. They consider alternative healing methods and not just medication and are often osteopaths or naturopaths.
2. Know your response to fats. Before diving into the keto diet or adjusting your carbs and fats, know how your body responds. There are extreme recommendations out there that tell you to eat 70% of your calories from fat, but this is just nonsense if you don’t know how your body will respond to that level of intake. I personally eat about 55% of my calories from fat, and keep tabs using an advanced lipid profile or NMR (nuclear magnetic resonance) lipoprofile. This advanced test will give you and your doctor a clear picture of how your body responds to fats and an increase fat load. I would do this test after a month or 6 weeks of your new fat-based diet to evaluate the impact. Also, if you get your genes screened through Self Decode, check out your inflammatory and heart health reports to get an idea of how much you should lean into this area. In the end, remember that it's not about the percentage and more about what your body is telling you.
3. Monitor your inflammation and sources of inflammation. Higher fat is not a problem as much as inflammation is. Control the foods that are inflammatory to you through precision testing like lectin tests, food allergy tests, food sensitivity tests. Monitor your gut microbiome and inflammation through a good stool test. Keep track of your overall inflammatory biomarkers like CRP (C-reactive protein), homocysteine, fibrinogen and ESR (erythrocyte sedimentation rate). Your functional medicine doctor will be able to discuss these testing options with you. I use Vibrant America for all of my gut tests, toxicity and food sensitivity tests.
4. Know your blueprint. This is worth mentioning again - one great thing we have access to today is genetic screening. While still in its infancy, this valuable tool is a powerful asset in your quest to implement a sustainable practice of fasting. I recommend Self Decode as the most comprehensive analysis of your genes. Their lifetime account is totally worth it for the constant influx of new research and reports you get, and knowing your genetic pre-disposition to fats, mineral and nutrient absorption, food, stress and a variety of other important factors will help you make the right decisions and customize this practice for your own lifestyle.
5. Keep tabs on your nutrients. Fasting is great, but many people do it wrong. One outcome of poorly implemented fasting and restriction in general is malnutrition. I recommend running a SpectraCell nutrient array every 6-12 months to evaluate your nutrient levels at the cellular level. SpectraCell is an industry standard with a patented, unique way of measuring nutrients that surpasses a simple blood test. For a podcast episode discussing the details of this test, checkout my interview with Nichole Herms from SpectraCell.
A Beginner’s Guide to Periodic Fasting
Besides intermittent fasting, you can employ regular water-only fasts (periodic fasts) to cleanse your body, heal and develop spiritually in your practice. This is a wide umbrella and is something that will develop over the course of your life with your own research and involvement. This guide is meant to help you get started to perform at least a 1-2 day fast, but remember anything greater than that requires supervision and training.
Always be careful, start slow and respect the practice. When you break your fast, do it also slowly and with nutritious, easy to digest food.
1. Prepare yourself mentally and plan ahead. Try your first 24 hour fast on a day you know will be low key, without pressure and commitments. Plan ahead, and start at nighttime the day before so that if you need to break your fast at night you can do it and still gain the 24 hour benefit.
2. Start slow. You can also try a daytime fast (this is done in many religions) and break your fast in the evening around 7pm or so. This is a good way to warm up to the practice so you know how your mind and body will respond to restriction.
3. Recruit friends. In my own life, I started a “Fasting with Friends” meetup group where we would do the practice together, stay in touch throughout the 2 days and break fast together when we finished. It helped to solidify the lessons through conversation and sharing, as well as gain support through the challenge of not eating for 2 days by having others to chat with.
4. Avoid anything that will rev you up. This means caffeine, stress, stimulation, work, excessive exercise, the Jacuzzi, supplements, drugs, smoking, video games or anything else that raises your energy. Fasting is about withdrawal, slowing down and tuning in. Allowing these things into your day only set you up for suffering and failure.
5. Stay hydrated and listen to your body. Drink water, but not too much. Make it a ritual to drink non-caffeinated tea. Avoid zero calorie sweeteners. Stop if you feel unwell, but also know that fasting is not easy at first and it’s normal for your body to detox or unwind.
6. Hack fasting with these “tricks.” While I recommend the full experience, there are a few things you can implement to make your first couple fasting experiences easier. Chewing no sugar gum, putting some butter in your tea, mixing fiber powders into your tea, consuming a pinch of salt here and there or playing some games are all ways to keep distracted or gain some extra willpower. Remember though, that at the heart of fasting is the ability to train your mind to be present and not rely on these crutches.
7. Focus on the positive. Fasting is a unique opportunity to develop yourself and your mind. Make a list of 10 things you can still enjoy that day that have nothing to do with food. Take slow, relaxing walks. Meditate or pray. Sleep, lay down or just rest. Journal. Clean a little or do some organizationally light tasks. Read or listen to something growth oriented. Do something creative or just sit out in nature and listen. The power of fasting will reveal itself to you in the quiet moments of the here and now. Set an intention for your fast and it will serve you that intention.
8. Try “done for you fasting” option. The program called Prolon by researcher Dr. Valter Longo I mentioned at the beginning of this guide is a program developed to help you with planned meals for 5 days to mimic a calorie restricted fast. I found the 5 day, 500 calorie per day regime much harder than doing a 1-2 day water only fast personally, but it is a great option and worth trying if you want a total reset without the planning.
Fasting is a powerful practice that I talk about in my podcast all the time, and it has given me a variety of benefits from the physical to the spiritual. How it will shape up in your own life will be a factor of the considerations discussed in this guide, your intentions and what is most sustainable. Do not buy the hype and cookie cutter molds. Do your own research and know why you are doing what you’re doing. Don’t go overboard, listen to your body and remember that fasting is a race that you win not by effort, but by patience.
Fasting, Stress, Adrenal Fatigue & Cortisol
Most people buying the hype of the keto diet and fasting are already stressed out, managing their cortisol levels poorly and have an unhealthy lifestyle or imbalance of work. Basically, most people aren’t in the position to be restricting themselves and causing additional stress to their body and adrenal glands.
Remember that, while fasting has many benefits, it is also a stress on the body and does increase cortisol. This is not a huge problem if you are resilient and healthy, but for most people out there who are suffering from some level of adrenal fatigue this can be a problem. If you are burned out and in a high-cortisol state, chances are you are also a “Type A” personality, go-getter and perfectionist. This type of personality is also the type that will commit to fasting and “go hard” with some extreme practices (trust me, I know because I am one of you).
This is why it is important to have a functional medicine doctor you are working with to balance out your hormones, diet, stress levels and recovery. Fasting is great, but it can do more harm and slow your recovery down if you are restricting your body from food and stressing your glands to produce more cortisol when they’re already burned out.
Be mindful, listen to your body, and incorporate fasting to the extent that it is useful and purposeful for your intentions without throwing yourself out of balance even more. You do not need to go crazy with fasting or have wildly short eating windows like all the hype suggests to reap some benefits.
For more information on adrenal fatigue and cortisol, a great book I recommend is this one by Dr. James Wilson.
Research Articles & Further Reading
Below are some valuable further reading articles to supplement your practice and research:
This is a comprehensive article looking at different intermittent fasting diets and calorie restriction as a practice. Very well informed and robust in information.
This article explains the impact of fasting on insulin reduction over the course of 24-48 hours, illustrating the largest benefits at around 18-24 hours. A great read for understanding why intermittent fasting using eating windows is not going to be as effective for insulin resistance as full day fasts (unless you can eat in a 6 hour window but that’s just impractical).
Another great article on the different stages of intermittent fasting and fasting, analyzing what happens to your body based on research from 0 hours to 72 hours of no food. This is important to know because many of the benefits that people think they’re getting (like autophagy, ketosis, etc.) kick in only after certain time lengths. Understanding this process helps you make decisions about what benefits you are truly after and why you are doing the type of fast you are doing.
In case you missed it above, this article is a great one to read and very well documented on the considerations with MCT oil, VDR gene, Vitamin D and so on. Especially if you plan on going “keto” with your intermittent fasting and using the MCT oil that has become such a fad, it’s worth it to read this and listen to your body.
Another great article on IF, how it relates to autoimmune conditions, who shouldn’t try it and the basics of IF practices.