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Is Fasting Right for You?

Everybody loves to eat. Eating is awesome! Some of us even go through our day just thinking about what we’re going to eat next and if we are among the majority of people, we have enough food in our homes to last us several weeks yet we go buy more every week at the grocery store.

But, what if I were to tell you that one of the most surprisingly healthy things you could do to live a longer, healthier, happier life was to stop eating? At least for a little while.

If you’ve been around the block a few times, you seen lots of diet fads come and go. Science is continually testing different theories and approaches to find out what happens when we eat more of this or less of that. But there is one practice that has stood the test of time, in just about every culture and in all corners of the globe; and that is fasting.

If we define fasting as simply going without food for a period of time then we all fast every night and “break” our fast each morning. The interesting stuff starts to happen when we extend that fasting window longer than the typical 8 to 10 hours.

Extended Fasting

Many religions have spiritually based fasting practices that encourage devotees to go without food for 1-7 days. Going without food can be a powerful way to try to gain control of your physical appetites and turn inward to spiritual connections.

For our purposes today, we will be taking this concept out of the context of religion per se and focusing on the physiological benefits of reducing our food consumption.

Metabolic Flexibility

Before we dive in to the details of fasting, it might be helpful to think about what is happening in our bodies when we eat and when we fast.

Our bodies need constant energy. This burning of fuel for energy is governed by many things, one of which is how much energy is available to us from the food we eat. When we eat a diet that contains fats, proteins, and carbohydrates, our body will digest them and either use them quickly or store them for later use. When there is a continual supply of new calories taken in, we often don’t burn the previous calories that were stored and we gain weight over time.

The healthier we are, the easier it is for our bodies to switch up what source of fuel we are going to burn. Our ancestors had to adapt to many challenging environmental stressors that modern man doesn’t have to adapt to. They had to run, climb, fight, lift, and kill in order to survive. Many times, there were long periods where their food sources were plentiful and many times when they weren’t. Those stressors selected for the bodies that were best equipped to handle them and over time, our genetics adapted to function in that environment.

Today, we are faced with a very different environment. We have an almost constant source of food and the foods that we have created are designed to be so convenient that we are put out if it even takes 30 minutes to prepare them. Our sedentary lifestyle isn’t helping either. We easily get ourselves both overfed and under nourished. This causes a loss of metabolic flexibility and actually drives the development of chronic disease.

It turns out that all we need to do is to start to mimic the lifestyle that our ancestors did to turn on those evolutionary protective mechanisms.

Risks of Fasting

Before I dive in to all of the proven benefits of fasting, I should offer some cautions. There are definitely times when fasting isn’t advised for more than the typical overnight fast.

  • Pregnant women should not fast for prolonged periods, especially during the 2nd and 3rd trimesters. Occasional fasts of 12 hours are well tolerated but to be safe, these should be done with medical supervision.
  • Newborns require food every couple of hours and don’t benefit at all from going without (and they’ll let you know about it if you even try 😩)
  • Young children shouldn’t go more than 12 hours or the time between bed and waking in the morning.
  • High level athletes require high amounts of calories during training and performance and fasting will quickly deplete those stored fuel sources. Fasting can be a very helpful option during the off-season though.
  • People with a medical history of eating disorders should be advised not to fast as it could lead to an unhealthy physical, mental or emotional response and trigger a relapse of their condition.
  • Type 1 diabetics should only undergo shorter fasts (under the direction of a trained professional) and avoid prolonged fasts.

Top 12 Benefits of Fasting

Stimulates Fat Burning

When we go without food, our bodies will first turn to stored energy called glycogen for fuel. As soon as that has been used up, our bodies will begin to breakdown fat to create ketones that can be burned for fuel.

Improved Energy Levels

It seems counterintuitive but when our bodies are burning these ketones, we burn energy “cleaner” and we can feel increased energy and even mental clarity that we didn’t have while burning glucose or glycogen.

Takes Stress off of Digestion

Digesting food is a very demanding process and requires lots of energy so when we fast, we can divert that energy to other important healing processes in the body. Fasting can also help heal the gut lining directly.

Reduces Inflammation

One of the ways that the gut can heal during fasting is by the overall reduction in inflammation throughout the body.

Stimulates Cellular “Autophagy”

Autophagy is the fancy word for when our immune system “prunes” out the old and damaged cells in our body to be recycled into new ones. This is a way to keep our bodies working efficiently and is a way of ‘anti-aging’ where only our healthiest cells are kept around.

Improves Repair of Our Genes

Research shows us that during times of famine and scarcity, our “longevity” genes get turned on and we become more efficient in what those cells do. This is regulated in part by a hormone called human growth hormone and that hormone goes up the longer we fast.

Stimulation of Stem Cells

We all have reserves of cells in our bodies that have yet to decide what type of cell they will become. These are called stem cells and science is learning more and more how important they are to the repair process in the body. It turns out that fasting actually increases the activity of these cells and accelerates repair of damaged tissues.

Improves Blood Sugar and Insulin

One of the negative outcomes of constantly eating is that we constantly need the hormone insulin to shuttle glucose into our cells to be burned. High levels of insulin eventually cause our cells to become resistant to the effects of insulin and our blood sugar goes up, leading to type II diabetes.

Reduces Risk of Chronic Disease

With everything that has already been mentioned, you can guess that fasting regularly can actually translate to a significant reduction in risk of development of chronic diseases like cancer, heart disease, diabetes, and Alzheimer’s to name just a few.

Improved Relationship with food

So many of us have become slaves to the food we eat. Unfortunately, many man-made foods also have been designed to drive cravings and blood sugar swings that keep us constantly stuffing our faces with more and more. Taking a break for a while can reset that natural hunger and taste mechanism and allow us to regain a healthy relationship with food.

Improved Mental Health

Many people observe that their brains work so much better when they are burning ketones instead of sugar. Just a quick warning, most people feel worse their first few days of a fast if they haven’t done it before since their metabolism isn’t yet flexible enough to kick in to ketone burning yet. If you stick with it for a few days, this nice brain/mood lift will kick in.

Improved Spiritual Health and Intuition

As mentioned before, virtually all religions have a practice of periodic fasting to elevated consciousness and gain control of their physical appetites. Many people feel that fasting can allow for clearer communication with God or their own intuitive gifts.

Fasting Options

There is a wide variety of approaches to fasting and finding the best approach for you is simply just a matter of trying them out. Some can be done every day of the week and other approaches might only be done once per quarter.

One of the most common approaches to fasting is called Intermittent Fasting or “time restricted feeding”. This means that we simply extend the hours between meals that are eaten each day. Some research suggests that restricting our feeding window to 8 or 10 hours each day is enough to stimulate a wide variety of healing mechanisms in the body.

Here are a few variations of Intermittent Fasting for you to consider.

Simple Fast

A simple fast is one where you don’t eat between dinner in the evening and breakfast the next day. Typically, this is a 12-hour break or what some would call a 12:12 program. This is the easiest place for people to start their fasting practice and can be done every day. This type of fasting is a great way to curb late night snacking.

Brunch Fast

A brunch fast is simply to push back the timing of breakfast a couple of hours so that there are 14 hours of fasting with only water.

Cycle Fast

A cycle fast is typically a 16 hour fast with an 8 hour window for eating, also called a 16:8 program. You might eat dinner at 6 pm and then not eat again until 10 am the next day.

Strong Fast

A strong fast would typically be a restricted feeding window of 18:6 where you would only eat two meals spaced within a 6-hour period.

Warrior Fast

Ancient warriors would march all day and only feast at evening time. Eating within a small window of 4 hours is one approach to this but there are some people who practice a variation of this called “OMAD” or One Meal a Day where they eat only 1 time each day.

Full day Fast

A full day fast is pretty straight-forward and involves abstaining from any caloric food for a full 24 hours.

Extended Fasts

Extended Fasts of greater than 24 hours are powerful for healing and lowering inflammation but they are more challenging and should be done once you are more adept at fasting and your body has gained some metabolic flexibility.

Alternate Day Fast

Once your fasting tolerance has increased, you may even try to simply eat one day and fast the next, alternating throughout the week.

5:2 Fast

Another fasting methodology that has been researched highly is called the 5:2 method wherein you would eat normally for 5 days of the week but fast for 2 non-consecutive days each week. Typically, those “fasting” days can have up to 500-600 calories of food but no more. For example, in this protocol one could do a low calorie intermittent fast on Sunday and Wednesday each week.

Extended Water Fast

There are many proponents of extended fasts of 3-5 days of only water intake. This approach creates the most dramatic rise in stem cell activation and growth hormone and thus profoundly stimulates the healing response. The major drawback is that it is very difficult to do while maintaining a semblance of normal daily life. This should be only considered for those with ample reason to do so and I suggest that it should always be done under supervision of an expert in fasting.

Is Fasting Right for You?

If you are totally a “newbie” to fasting, you might want to just start at the top of the list I’ve just provided and gradually work down the list until you find a rhythm that fits your lifestyle and helps you gain the amazing benefits of improved mental, physical and spiritual health.

Keep in mind that fasting means you don’t eat or drink anything except plain water for the alloted time of the fast. Water is important for the increased healing processes stimulated by fasting to take place so don’t skip the water.

If you have any questions about whether fasting is right for you, please reach out to our office and we can walk you through the thought process and determine a good approach for you.

4 responses to “Is Fasting Right for You?”

  1. Carol Curtis says:

    Greetings Dr. Jerry,

    I’m happy to see that you are now onto water only fasting. I remembering talking with you about this several years ago, and you didn’t seem to support this type of fasting. Anyway I still do 5 day water only fasts every 3 to 4 months, and they are wonderful times for me. And as I mentioned years ago, I have been doing water only fasting not always regularly for the past 25 years. Since I’ve never been in a situation where I could be monitored during my fasts, and since I started with 2 to 3 day fasts originally and worked up to more days, once doing a 14 day water only fast, it doesn’t worry me that I do fasting without supervision, although definitely that is the best way to do it. Also since I still don’t take any medical prescriptions, only supplements which I stop while fasting, then for me there is nothing to worry about. I find that preparing for fasting is more psychological than physical – deciding when to do it, and preparing myself mentally to do it, and then doing it. I also do intermittent fasting, basically not eating breakfast, since I’m not hungry anyway, and mid morning having my greens drink. Anyway just wanted to connect to let you know I’m happy to see you talking about fasting. Hope all is well, and yes I’m still in the Marshall Islands and working full time, maybe someday I will retire.

    Bar iokwe, greetings and love (in the same word)

  2. Duggar Wellness says:

    Carol, it was good to hear from you! I’m glad to see you continue to make your health a priority with practices that work for you. It is always my intention to offer information on health practices based on my experiences, patient experiences and supported research and there have been a lot of that these past few years. I highly recommend fasting but find that it is a very individualized process and that begining something new is always best if supervised by someone knowledgeable in that practice.

    Best wishes to you and your beautiful Marshall Islands!

  3. Sydney says:

    Thanks for the great post on fasting. I have seen a lot of benefits from incorporating it in my life. I am wondering if there is a protocol for what you eat going into and coming off of an extended water fast?

  4. Duggar Wellness says:

    Sydney, it is super important when coming off an extended fast (4+ days) so that insulin and electrolytes don’t get off balance. Depending on how long the fast has been it may be best to have physician supervision when coming off of the fast.

    Recommended foods for after a fast are bone broth, soft cooked veggies, low-glycemic fruits like berries and fermented veggies for a couple of days keeping your calorie intake low. Add in meat, dairy, and raw veggies after 3-4 days.

    An excellent resource for fasting is the book The Complete Guide to Fasting: Healing Your Body Through Intermittent, Alternate-Day, and Extended Fasting by Dr. Jason Fung and Jimmy Moore

    Or you can read the Summary Guide to the same book