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April 23 2019

Top 10 Fasting Mistakes and How to Avoid Them

By Guest

Folks, you know I’m a long-time believer in intermittent fasting for longevity, autophagy, mental clarity, fitness performance, metabolic health, and more. I’m excited that Dr. Jason Fung has stopped by the blog today to share a bit about common fasting mistakes. Enjoy!

So, you’ve decided to add some fasting to your lifestyle. Excellent. No matter how much you have (or haven’t) read on the topic, you’re likely to find aspects of fasting to be challenging or even frustrating. It can be hard to stay on track when you’re feeling hungry, irritable and not really noticing any changes.

It’ll become tremendously easier once you begin to experience the health benefits of fasting, but we all know it takes a little while for that to happen. Benefits like mental clarity and improved energy will show up sooner than significant weight loss. Plus, the benefits you experience will depend on what kind of fast you’re doing and how well you stick to it.

But if you’re making fasting mistakes, you might never accomplish the benefits you were hoping for. Before you throw in the towel, I want to help you identify some possible fasting pitfalls you might not be aware of and also help you avoid them. Plus, don’t miss the Number One reason fasts fail, shared at the end of this article.

1. You’re Snacking or “Grazing”

Look, the entire purpose of a fast is to contain your eating within certain windows of time. Snacking or “grazing” all day long is basically the opposite of fasting, so stop thinking that you can get away with it. Fasting is “on” or “off”—there is no gray area. Even having “just a bite,” no matter how healthy or how little, will almost invariably kick your body out of fasting mode and will interfere with the healing process responsible for fasting’s many benefits. It also creates a situation where your body is producing insulin all day long. Bad idea.

Avoid grazing by putting snacks and food out of sight. The phrase “out of sight, out of mind” really applies here. You’ll be amazed how much easier it is to bypass snacking when the food isn’t sitting right in front of you. If you snack out of habit, get creative and find new, non-food based habits. If your snacking comes from genuine hunger, you may need to re-evaluate the meals you eat during your eating window. Make sure you’re getting enough healthy, unsaturated fats with each meal as these will keep you satiated for longer.

2. You Aren’t Drinking Enough Water

This is not only a common fasting mistake, but a mistake most people make no matter what their diet is. Drinking a minimum of eight glasses of water daily is essential to staying hydrated and healthy. Some signs that you aren’t drinking enough water include dizziness and lightheadedness, feeling tired, or constipation.

Even worse, when you don’t drink enough water, your brain may try to trick you into thinking that you’re hungry, so you get the vitamins and minerals you’re lacking. Minerals like potassium and magnesium are essential to your brain health. So don’t be surprised next time you feel hungry but find that drinking a glass of water makes the appetite disappear. Various kinds of tea are also a satisfying way to hydrate, or try some bone broth if you’re truly struggling.

3. You Aren’t Consuming Enough Salts

Speaking of vitamins and minerals, appropriate salt intake is vital to your health. Now, when I say “salt,” I’m not talking about the kind you put in a shaker. I’m talking about electrolytes, which are essential to your diet. Sodium (Na), which is also commonly known as table salt, is one of these electrolytes, along with potassium (K), magnesium (Mg), calcium (Ca), and chloride (Cl).

How can you tell if you’re low on electrolytes? Some symptoms of electrolyte deficiency are anxiety, irritability, trouble sleeping, muscle spasms, fatigue, digestive issues, and dizziness. If these are the kinds of symptoms you experience during your fast, lack of electrolytes could be the answer. Try taking some pink Himalayan rock salt and placing it under your tongue to dissolve. You can also try drinking some pickle juice — just make sure it’s from high-quality natural pickles and not the kind made with sugar.

4. You’re Eating Right Before You Go To Sleep

Your body needs time to digest all the food from your last meal before you go to sleep. If you’ve scheduled your eating window to happen right before bedtime, your body will be taking all the time you’ve allotted to rest to digest instead. That takes energy, and instead of waking up feeling restored and ready to take on the day, you’ll just feel tired.

When you’re following a fasting plan, a seven-hour window is an ideal amount of time to leave between your last meal and when you go to sleep. Even three or four hours is enough to make a difference. Unfortunately, with crazy work schedules and early mornings, a lot of people aren’t able to stick to that three- or four-hour window. It’s more like get home, eat dinner, and go straight to bed. If this is you, the next best thing is to eat a light meal, like salad, and avoid a meal filled with carbohydrates and protein.

5. You’re Eating Too Much of Some Food Groups

When we cut certain foods from our diet, especially carbs, it’s easy to rely on other food groups, like nuts and dairy. They’re readily available and a staple of most diets.

Nuts are a low-carb, healthy fat option, but only in small amounts. They’re great to add to fruit or veggie salads, and they’re easy to grab a handful of when you need a quick snack. But those quick snacks can add up, especially on top of eating full meals. Nuts are high in good fat, low in carbs, and are a good source of protein, but too much protein can be detrimental to your fast. Excess protein that your body doesn’t need is converted to glucose and stored as fat. If you’re fasting to lose weight, this is the exact opposite of what you want.

Dairy, the other easy food group that too many people defect to, can cause inflammation, upset stomach, bloating, gas, and other kinds of discomfort. If this is a pattern you’ve noticed with your own health and eating habits, try cutting out dairy for a few weeks and see if these symptoms improve. If you haven’t noticed these symptoms, be more mindful of your eating habits and track how you feel after eating dairy.

6. You Aren’t Eating Enough of Certain Food Groups

As easy as it is to eat too much of one food group, it’s equally easy to not get enough of another. Just because you can eat “whatever” you want during your eating window doesn’t mean you should. Empty calories and junk food are momentarily satisfying, but they don’t fuel your body. Eating the right foods provides your body with the nutrients it needs to thrive throughout the day; these foods will also keep you feeling fuller, longer.

Vegetables are one of the best food groups to keep you nourished and thriving. They’re low calorie and they provide different vitamins and minerals like potassium, fiber, folate, vitamin A, and vitamin C. Fruits are also healthy, but don’t overdo it, as most are high in sugar. Fruit juices typically have added sugar as well. Naturally flavored drinks and teas are the healthiest option. Nuts are high in fat and a good source of protein, as are eggs. Refined carbohydrates and sugars are highly unnecessary for your body and if you’re going to include them in your meals, there should be very little.

7. You’re Pushing Your Body Too Hard

Did you dive off the deep end and go from zero fasting to attempting 24-hr fasts every other day? Back up and take a more moderate approach first. Don’t expect fasting to be easy right away. Not only will your body need time to adjust, but your mind will, too. If you’ve been accustomed to three square meals a day, plus snacks and calorie-filled drinks, your body has gotten used to this routine.

Your body needs time to adapt. First it burns through stored sugar and then it will start burning body fat for energy. Start slow and get a feeling for this new practice. You can start with a twelve-hour fasting period and twelve-hour eating window. When eight hours of that fast are during your sleeping hours, this window is relatively easy. Once you’ve become accustomed to this schedule, you can reduce your eating window to ten hours. Continue decreasing your eating window by two hours every one to two weeks, until you’ve hit the fasting period you want.

8. You Have the Wrong Mindset

Fasting provides your body with everything it needs to thrive, but without the right mindset, you’re bound to fail. Focusing on the negative, like not being allowed to eat certain foods or at certain times, will easily spiral into other negative self-talk. The harder you are on yourself, the more difficult it is to achieve success.

Rather than thinking about how hard the fast is, focus on the positive that will come out of it. Fasting allows your body to heal. Fasting can help you lose weight. You’ll feel more energized and have a clearer mind. Whatever the reason you’ve chosen to fast, focus on that. Fasting with a friend, family member, partner, or online community is another way to hold yourself accountable and can be very helpful.

9. You’re Too Stressed

When you’re stressed, your body releases a hormone called cortisol. Cortisol is problematic when fasting because it can prompt your body to break down muscle tissue instead of fat. When fasting, your body should tap into stored body fat and preserve your healthy muscle tissue.

If you’re stressed on occasion, this shouldn’t cause much of a problem. But if you’re chronically stressed, that constant release of cortisol can lead to a breakdown of muscle tissue.

Not sure if you’re stressed? Here are some symptoms:

  • Teeth grinding
  • Muscle tension
  • Headaches
  • Apathy
  • Anger
  • Digestive problems
  • Fatigue
  • Trouble concentrating

Alleviate stress with deep breathing, positive visualization, an epsom salt bath, and stress-relieving teas. If you can, take some time off from work. If you’re an outdoorsy person, relax in nature.

10. You’re Inactive

Being inactive is one of the biggest mistakes people make during their fast. If you aren’t eating, you should rest and save your energy, right? Wrong. Exercise is a great way to improve your fasting. Activity increases fat burning and boosts circulation. Going outside and getting some sunlight and fresh air can improve your mood, making you more likely to stick to your fast. Movement generally makes people feel better than sitting on the couch inside all day; being inactive makes you cold, tired, and unfocused.

Since a lot of people work sedentary jobs that tie them to a desk all day, exercise isn’t a convenient way to stay active. But taking a short walk or stretching are two easy ways to get your blood flowing throughout the day.

Fasting shouldn’t be synonymous with suffering. If you’re feeling deprived during your fast, be sure that you aren’t making any of the above fasting mistakes. Ease yourself into your fast, stick with it, and enjoy the results when they come with time.

But there’s one more—in fact, the number one reason fasts fail….

Can you guess what it is?

***Giving Into Cravings

Which is why I want to tell you about my new favorite secret weapon for staying fasted longer and with less difficulty: Pique Fasting Teas. Why tea? The combination of catechins and caffeine gives you a higher chance of experiencing tangible benefits from fasting. It suppresses hunger cravings, boosts calorie burn and supports malabsorption of unhealthy fats and sugars.

These Fasting Teas include ingredients targeted at maximizing the fasting experience:

1) Organic highest ceremonial grade matcha, which increases levels of l-theanine to calm and tide you through your fasts with ease. 2) Organic peppermint, which is a natural appetite suppressant with calming properties. 3) Proprietary blend of high catechin green Tea Crystals, which regulate the hunger hormone ghrelin and increase thermogenesis (burning fat for fuel). This helps you to stay fasted and see quicker results. 4) Additional plant ingredients including ginger and citrus peel to support digestion and enhance autophagy.

As with all of Pique’s teas, you can rest assured these are pure and Triple Toxin Screened for pesticides, heavy metals and toxic mold. For a limited time only, if you order through the Mark’s Daily Apple link, you can get up to 8% off and free shipping (U.S. only).

Thanks again to Dr. Jason Fung for today’s post. Have questions on fasting protocols or missteps? Share them below, everybody, and have a great day.


19 thoughts on “Top 10 Fasting Mistakes and How to Avoid Them”

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  1. Great list and have checked most of the mistake boxes at one time or another! The water and salt references were good reminders and getting enough sleep sure helps. After much experimenting, an eating window between 12:00 Noon Lunch and 6:00 Dinner is my sweet spot.

  2. Perfect timing on this post as my health coach/business partner and I just launched our first online class on intermittent fasting/time restricted eating! I’m going to post this for the participants to read. Thanks Dr. Fung!

  3. Thank you Dr. Fung. I like your ideas a lot and frequently repost your messages on Facebook. But . . . I object to your blanket statement to drink 8 glasses of water. That idea has been completely discredited.
    It is important to stay hydrated but that hydration can come from foods not just water. Too much water can wash minerals out of your system.
    I have congestive heart failure. I have to be very careful of fluid intake. Too much water has put me in the ER more than once. I have been told, by an MD, to sip throughout the day. That, apparently, is the Ayurvedic approach.
    Otherwise, a good article.

    1. Agreed. As I recall, the Dr who coined the amount of water to be consumed, included the water in the foods we it. Sometime later it was ignored and we started to hear that we should drink 8 cups.

    2. Good point Harry. I drink mostly distilled water and put 10 drops of concentrated minerals into each glass. I usually have a couple of cups of bone broth each day, so that’s definitely gotta count right!? 🙂

      1. I’m a big fan of Dr. T. Stuff is not cheap, I take 15 grams a day due to ongoing chronic fatigue I’ve been battling for years.

  4. Good article. I’m definitely a fan of grazing. “On or off” a good descriptor

    1. The little stevia/splenda packets you see everywhere are the worst. Would mix it in w some cao cao and ground flax in as a nibbler, and go through 40 of things before I knew it. Probably a better snack than lots of other things but adds up a bit.

  5. There is a huge relationship between point #10 and the last… If you are active, your body is forced to pull calories out of storage, and into your bloodstream. Your hunger will switch off somewhat, especially if you do something strenuous.
    If you sit still, however, and allow yourself to relax, you will be hungrier. And having nothing active to focus on will allow you to focus on your hunger. This is how most of my fasts have ended…

  6. I know the sweeteners, sugars gives your brain idea food is plentiful. Having 40 splenda packs (which have .4 carbs I believe) back to back not really part of, “when hunger naturally ensues” as mark puts it in one of his books lol. Think there’s a natural rhythm w winter w this in winter months too (not just Holiday peer pressure).

  7. I respect your ability to do a job like that and be so clear minded. Definitely the disordered exercise and sleep patterns will screw any sort of moderation and consistency in quite a lot of things. Fight or flight at it’s most potent.

  8. Interesting read. Dr Fung, you have said that “Excess protein that your body doesn’t need is converted to glucose and stored as fat”. What’s your opinion about the position that Gluconeogenesis is Demand-Driven, not Supply-Driven? Thanks

  9. Follow up. Meat and fats are satiating so it would be hard to over eat; at least for me

  10. Kind of annoying that this entire article was a big advertisement for his teas.