Everything You Need to Know About How to Fast
Intermittent Fasting for Weight Loss
Fasting has been used for centuries, as a powerful healing tool to cure disease, kill cancer cells, lower cholesterol, reverse diabetes, improve insulin sensitivity... the list goes on!
I love fasting. I think our society would benefit greatly from making fasting a regular part of our lives. And because of my own success with it, I REALLY get lit up when talking about it!
I've been practicing intermittent fasting for a few years now, and have seen tremendous health benefits from it. By practicing intermittent fasting, I've eliminated my hypoglycemia, nearly obliterated my PCOS symptoms, and lost weight.
And because fasting has been an important part of my personal healing, the topic has come up quite a bit in my conversations, both personal, and professional.
As it turns out, what I am gathering from these conversations, is there is a lot of confusion as to what "intermittent fasting" is, how it's intended to be used, and what its benefits are. In fact, most people I hear this from aren't really aware that they are confused. They've been misinformed.
And so... I am here to help clear the air.
The Dirty Truth About Diets
I'm clearly an advocate for fasting. I have seen immense benefits from fasting, in my own health as well as in others'.
However, it is important to recognize, when beginning ANY new dietary regimen, to first consider your body's unique health needs.
Put differently, eating [vegan/gluten-free/low-fat/keto/paleo/vegetarian] is NEVER what determines whether or not you are "healthy."
What DOES determine whether or not you are "healthy" is assessing your body's unique health needs, and addressing them specifically. One diet is never "healthier" than the other without consideration to bio-individuality.
That said, I would never recommend fasting to anyone who has not been properly assessed, to determine whether it's a safe and viable option for their body.
Let's look at some of the more common confusions about fasting.
WHAT FASTING IS NOT
Fasting is not:
calorie restriction
forgetting to eat
an excuse to eat whatever you want on non-fasting days
a way to atone for dietary sins
WHAT FASTING IS
Fasting is:
intentional
evolutionarily a normal way of life
an effective & safe method of increasing sensitivity to insulin
facilitates the clearing and recycling of damaged cells
easier to stick with than calorie restrictive diets
WHO IS FASTING FOR?
people prone to insulin resistance (Type-II diabetes, PCOS, hypoglycemia)
people who find it difficult to lose weight
people wanting to optimize cellular health
people prone to cancer
people wanting to maximize lean muscle building
people who are well nourished, and have above-normal BMI
WHO IS FASTING NOT FOR?
those who are pregnant
female-bodied people, during their menstrual cycle
children
people who are underweight, malnourished, or below-normal BMI
people with an eating disorder
Fasting Terminology
The term that's probably most familiar to you, is Intermittent Fasting (IF).
Since IF resurfaced as a trendy new weight loss diet a few years ago, we were mistakingly referring to Time Restricted Feeding (TRF) as IF.
As commonly happens when a trend gets marketed by misinformed influencers, we have simply just adopted the two as interchangeable (which is fine, everything is fine...).
I'm going to explain the differences between those terms, as well as a few others, to help you understand better when we begin discussing how to fast, and the benefits of different types of fasting.
Time Restricted Feeding (TRF) = Eating all your calories within a small window of time each day. Commonly described as "16/8," or "12/12," meaning, you consume all your calories (as many as you like) within only an 8 hour window, consequently "fasting" the other 16.
Intermittent Fasting (IF) = Sometimes referred to as Alternate-Day Fasting. IF is a no-calorie fast for anywhere from 24-72 hours, and is followed up with a strategic re-feeding regimen. The important piece here is the re-feeding (more on this later).
Think of it like this: the word "intermittent" means to do something at irregular intervals. IF is typically done 1, 2, or 3 days out of the week, each followed by a re-feeding. Whereas a 16/8 TRF is typically regularly done every day (it's consistent, steady).
Extended Fasting (EF) = Fasting that lasts longer than 72 hours is typically referred to as Extended Fasting." Don't panic! There is plenty of research to show that extended fasting does not starve our bodies, does not break down muscle, and has huge benefits, but it is not for everyone. We will get more into this later.
Intermittent Fasting Benefits
When fasting comes up in conversation, I most commonly talk with people who are doing it for weight loss.
I mean, it's extreme calorie restriction, right? Why wouldn't you lose weight?
This, my friends, is the response of a misinformed culture.
In reality, if you are properly re-feeding after a fast, you are not restricting calories. The full benefits of fasting go far deeper than just weight loss.
Fasting benefits:
IMPROVES CELLULAR HEALTH - Cells take on severe damage from our western diet of processed foods. The amount of sugars and starches we eat cause immense free radical activity, damaging the structure of our cells, leading to chronic inflammation and tissue damage. Toxins from air, water, & pesticides cause mitochondrial dysfunction, and can interfere with nutrients getting in and out of cells.
The health of our cells is essential to ensuring the nutrients we take in are able to be used. Healthy cells are necessary for energy production, nerve function, and immune function.
Our bodies have a system for repairing damaged cells (called autophagy), and destroying harmful cells (called apoptosis). These processes happen in times of fasting. When we are constantly snacking, grazing, and especially on highly processed foods, we do not give our body the chance to heal.
Proper fasting will improve your body's ability to heal damaged cells and eliminate harmful cells (cancer).
INCREASES FAT BURNING - Going back to my Sugar Balance post, you might recall that sugar, in the form of glucose, is needed to produce energy. When insulin has shuttled all the glucose it can into your cells for energy production, your body stores excess glucose in the form of glycogen. When glycogen stores are full, the rest gets converted to triglycerides and are stored as fat tissue.
Our bodies can store about 24 hours’ worth of glycogen in the liver, but there is no limit on how much fat that can be stored. In times of low glucose (such as in fasting), our body will use the glycogen to produce the energy it needs. Once those stores are used up, our bodies will convert triglycerides into glucose (or ketones) to be used for energy (known as fat-burning).
Proper fasting, especially for longer than 24 hours, will increase fat burning in your body. When done intermittently, and with proper re-feedings, your body can be "taught" to burn fat more efficiently.
IMPROVES INSULIN SENSITIVITY - As we know, when glucose enters the bloodstream, our body responds by releasing insulin from the pancreas. Insulin's role is to shuttle the glucose into cells. Think of your cells as having a locked door, and insulin is the key to the lock (insulin receptor).
Eating processed foods, starches, grains, sugars, etc., causes glucose levels to spike, causing insulin to be released more rapidly. When we eat like this frequently, insulin is, you guessed it, also released more frequently.
Over time, our cells begin to react to the abundance of insulin by saying, "we've had enough!" and reduce the number of insulin receptors available. This is the start of "insulin resistance."
Fasting reduces the amount of glucose in the blood, thereby reducing insulin response, thereby increasing insulin sensitivity. With proper eating and stress management, symptoms of hypoglycemia ("hangry") disappear.
**It's important to mention here, that most foods, not just sugars, will cause insulin response.
IMPROVES MICROBIOME - If you have ever been told you have leaky gut, Irritable Bowel Syndrome, or digestive issues like bloating, belching, farting, or general abdominal discomfort, it is possible you have a bacterial imbalance in your gut.
Simply put, your body is supposed to have certain types of bacteria, and those bacteria should only be living in your large intestine. When bacteria begins to live and grow in your small intestine, that's when we begin to see issues like the ones I mentioned above.
Our bodies have a mechanism for preventing this from happening, and guess what--it occurs during the absence of food...
It is called the Migrating Motor Complex (MMC), and it is what causes the "growling" when you're hungry. A hormone called motilin triggers a series of events, such as the release of bile and pancreatic enzymes, and smooth muscle contractions, which "sweep" out the small intestine of any bacteria.
When we constantly graze, and especially foods containing starches, sugars, or grains, we not only don't allow the MMC to do its job, but we are also feeding the harmful bacteria that shouldn't be there, allowing them to thrive and cause further imbalance.
Fasting gives way to the MMC, helping to reduce and eliminate unwanted bacteria, improving your digestive health.
INCREASES LEAN MUSCLE MASS - Research has shown that in the absence of insulin, our body has significantly elevated Growth Hormone levels. You've probably heard of GH used by body builders and athletes.
Fasting helps you increase these levels naturally, without the use of potentially harmful supplements. With a strategic fasting + re-feeding plan, fasting will help you build lean muscle, more effectively.
Intermitent Fasting How-To
Fasting is simple. Fasting is not eating or consuming calories. Its simplicity is, in part, why I think it's much easier to comply with than calorie restrictive diets, or specific food-restrictive diets.
It's what makes fasting a sustainable & effective approach to health.
Which type of fasting you choose, Time Restricted Feeding, Intermittent, or Extended, depends on what you want out of it, and what your body can safely tolerate.
Time Restricted Feeding: This is essentially a calorie-restrictive diet, with a few added perks.
does: improve insulin sensitivity & MMC function
does not: facilitate autophagy, apoptosis, or fat-burning
Intermittent Fasting:
does: improve insulin sensitivity, MMC, autophagy, fat-burning, & lean muscle
does not (depends): facilitate apoptosis. Apoptosis generally occurs after 48 hours of fasting, so depending on the duration of IF, you may or may not get this benefit.
Extended Fasting:
does: improve insulin sensitivity, MMC, autophagy, fat-burning, lean muscle, & facilitate apoptosis
All of the benefits apply here. Which makes it easy to say, "why don't we all do that?!"
But EF is not for everyone. In fact, all of these fasting techniques should be approached with caution, and gradually progressive, even TRF. If you are new to fasting, always approach fasting in small increments, gradually working your way up.
This is a perfect transition into fasting DOs and DON'Ts.
Fasting DOs
DO... Always consult a qualified health care practitioner prior to changing your eating or supplement regimen.
DO... Always listen to your body. You are not a robot. Waves of hunger are normal during a fast, but feeling any signs of unwell (e.g. lightheaded, queasy, feverish, pain, etc.), are signs you should STOP fasting immediately.
DO... Be intentional about hydration. A lot of our daily hydration comes from certain foods we eat, especially fruits & vegetables. Be intentional about drinking at least half of your body weight, in fluid ounces, of water. Adding Himalayan Sea Salt to your water (just a pinch) will provide necessary electrolytes to hydrate you more effectively. Avoid dehydrating factors, like excess caffeine. It is okay to drink small amounts black coffee, green tea, and herbal tea.
DO... Properly re-feed your body. As we discussed earlier, fasting is not an excuse to eat whatever you want during non-fasting times. In regard to cellular health, especially, fasting is what allows our body to clean up damaged parts of cells, but re-feeding is when the cells are repaired. Be intentional about eating habits that include lots of vegetables, quality whole-food proteins and fats, and only consuming grains in their whole, unprocessed forms. On re-feeding days, consume a bit more food than you typically would. I'm not suggesting you put a buffet out of business, but as an example, if you typically have 2 eggs and half an avocado for breakfast, consider having 3 eggs, and a whole avocado on a re-feeding day.
DO... Prioritize sleep. Sleep is when our body hits healing mechanisms HARD, whether fasting or not. Turning off screens 2 hours prior to bedtime, avoiding sugary foods close to bed time, not drinking caffeine past 10am (yes, that early) - set guidelines in place that ensure you will get quality sleep, especially when fasting.
DO… Follow a normal circadian cycle. Both when fasting and not fasting, plan your activities (including eating) during daylight hours, resting during dark hours. This is the natural rhythm of our bodies and will hugely benefit your body’s ability to digest food and assimilate nutrients, in order to ensure proper cellular healing.
DO... Continue normal routines. This may be challenging as a beginner, but you will find over time, that you have plenty of energy and mental clarity (if not improved) to do your normal workouts, projects, and tasks. Fasting does not mean you need to stop all of these things, although I do advise beginner fasters to stick with light cardio and/or weights, and to work out with a trusted friend until they feel more comfortable.
DO... Stay busy. Staying busy is the easiest way to keep your focus off of food.
DO... Plan your fasts according to your schedule. The loveliest thing about fasting is that YOU make the calls. With food-restrictive, or calorie-restrictive diets, you have to be ON all the time. But fasting allows flexibility, while still giving room for success! Set yourself up for success by switching it up if needed, and give yourself room for grace if you end up backing out of a fast.
Fasting DON'Ts
DON'T... Consume calories. There are a lot of variations of "fasting" out there, and lots of misinformed media posts. When a resource tells you it's okay to consume 500-600 calories during a fast - that is not fasting, friends. That is calorie restricting, and it will not provide the same benefits as fasting.
As Dr. Jason Fung points out in his book The Complete Guide to Fasting, all foods produce an insulin response. When insulin is present in the blood, fat stores cannot be released. When calories are decreased, but insulin levels remain, our body preserves energy by slowing metabolism. But when insulin is absent (as it is with fasting), the body releases fat stores for energy use, rather than slowing metabolism.
If you've worked with me before, you know my whole career is based on eliminating the rigidity of diets and eating to suit your body's specific needs. If calories must be added to your fasting routine, opt for quality, whole-food fats (coconut oil, MCT, grass-fed butter). These cause the lowest insulin response.
DON'T... take any tissue-building supplements (folic acid, protein powders, collagen, etc.). Instead, save them for your re-feeding phase to enhance the cellular "clean-up" that fasting facilitates.
Your Move!
You now have some tools in your belt, the air is cleared, and the world is your oyster (someone please tell me what that means!).
Ask yourself what you want out of fasting, then decide which technique is best for your body’s needs.
Have questions about intermittent fasting? Ask them in the comments below.
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