6 Intermittent Fasting Mistakes to Avoid

Lisa Fields
by Lisa Fields
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6 Intermittent Fasting Mistakes to Avoid

Proponents of intermittent fasting claim it helps with weight loss and can boost energy and mood levels. But if you’ve decided to try limiting your eating to a certain timeframe and are having trouble adjusting to the plan, it may be because this eating style is vastly different from your previous eating habits. You may also inadvertently be making mistakes which can make your transition more difficult.

Here are six common mistakes people make while trying to adopt intermittent fasting and how to fix them:

If you normally eat every 3–4 hours and then suddenly shrink your eating period to an 8-hour window, you’ll likely feel hungry all the time and discouraged. “Some people quit if they start out by fasting for too many hours without an adjustment period from a previous eating style,” says Krista Varady, PhD, associate professor of kinesiology and nutrition at the University of Illinois at Chicago and author of “The Every-Other-Day Diet.” It may take 10 days to two weeks until you stop feeling hungry when you’re fasting.

The fix: Gradually stretch out the number of hours you go between meals until you reach a 12-hour eating window, suggests Varady. Then move to a 10-hour eating window and reduce by small increments until you reach your goal.

“It can be easy to overeat when a fast ends either because you’re feeling ravenous or you justify to yourself that you’re making up for lost calories,” says Dr. Jason Fung, co-author of “The Complete Guide to Fasting: Heal Your Body Through Intermittent, Alternate-Day, and Extended Fasting.” But this can backfire if you’re fasting for weight loss and also cause other problems like stomach aches, notes Fung.

The fix: Plan ahead. Prepare a healthy meal that’s ready for you when your fast ends and make sure to eat whole ingredients when possible including healthy carbs like whole grainslean protein and plenty of veggies, says Fung.

Most people drink water, black coffee or tea while they’re fasting. If you can’t stand your coffee black, you might add a splash of milk or a packet of sugar without considering that these things break your fast. “Keep the butter and coconut oil out of your coffee,” says Gin Stephens, author of “Delay, Don’t Deny: Living an Intermittent Fasting Lifestyle.”

It’s also important to “avoid any protein-filled liquids such as bone broth, because that can halt autophagy [the cellular process that breaks down and recycles damaged molecules], which you want to promote while fasting,” explains Stephens.

Similarly, you should also give up diet sodas. “You don’t want anything heavily sweetened, even if it’s calorie-free,” says Fung. “Zero-calorie sweeteners still have a negative effect on insulin levels, stimulating the appetite and making you want to eat.”

The fix: Track your hydration using an app like MyFitnessPal, which can help keep you accountable and stick to water, plain tea or black coffee while fasting.

“Intermittent fasting focuses on when to eat but largely overlooks nutrient quality of foods,” says Whitney Linsenmeyer, PhD, RD, spokesperson for the Academy of Nutrition and Dietetics. “Those experimenting with intermittent fasting still need the same essential nutrients.” In other words, if you stick with processed foods in lieu of whole foods that comprise a well-balanced diet, intermittent fasting won’t help you reach your health goals.

The fix: “Gradually change your diet along with your eating schedule by incorporating healthier foods slowly,” suggests Stephens. This prevents you from trying to overhaul everything at once, which is more sustainable.

If you’ve always had a pre-workout snack, exercising while fasting may seem foreign. But “your body has plenty of energy stored in your body fat to use when there’s no food,” explains Fung. As with any diet or exercise plan, it’s a good idea to check with your doctor first, but exercising can be safe with intermittent fasting.

The fix: Keep up with your usual workout routine or try something low-impact like walking. If you fast overnight and exercise in the morning, “you can eat a protein-rich meal after, which helps you increase the rate at which you build muscle,” says Fung.

“You might be inclined to opt out of dinner with friends or say no to birthday parties because you’re fasting,” Linsenmeyer says. “In that case, it might not be enjoyable or sustainable long-term.”

The fix: Shift your schedule forward or backward by a few hours on days when you’ve got plans with friends so you can still enjoy socializing. “It’s a lifestyle, and it has to fit into life’s special occasions,” Stephens says. “Intermittent fasting can be flexible.”

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About the Author

Lisa Fields
Lisa Fields

Lisa Fields is a full-time freelance writer who specializes in health, nutrition, fitness and psychology topics. Her work has been published in Reader’s Digest, WebMD, Women’s Health, Shape, Self and many other publications. A former lifeguard, Lisa swims regularly to stay in shape.You can read more of her work at http://www.writtenbylisafields.com/.


23 responses to “6 Intermittent Fasting Mistakes to Avoid”

  1. Avatar Todd smith says:

    Thanks, the fasting advice was adorable. But, I prefer to get my fasting advice from the real researchers of Keto/ IF/ EF & Carnivore.

  2. Avatar Lindsay Gil says:

    Its nonsense to say a packet of sugar won’t break the fast but diet soda will. Anything that causes an insulin spike is breaking the fast by causing the liver to take up glucose and store it (as glycogen) rather than releasing glycogen and using reserves. You have fundamentally misunderstood this High School Biology!

  3. Avatar Gin says:

    I was quoted for this article in the section about coffee, and it sounds like I am endorsing sugar and milk in your coffee. That is NOT what I recommend for fasting…I would never endorse sugar and milk. I recommend that if you drink coffee, it should be black. I am not sure why that milk and sugar recommendation is in the section with the quote from me. –Gin Stephens, author of Delay, Don’t Deny: Living an Intermittent Fasting Lifestyle.

    • Avatar Brian says:

      You didn’t read close enough. It says people add milk and sugar “without considering that these things break your fast”.

    • Avatar Brian Kline says:

      Gin, did they update/edit the article after you posted this comment? Because it’s correct now.

  4. Avatar salbers says:

    Articles like this by undocumented contributors cause great harm to sincere readers. EACH CONTRIBUTOR needs to be vetted to prove they have HEALTHFULLY lost weight using intermittent fasting or their pontifications should be ignored as useless or harmful. Now, onto the mistakes in the “Mistakes list’.
    1. “Gradual changes” NEVER WORK and always result is demoralizing backsliding failure. Solution: Make drastic changes and stick to them through temporary hungar is the guaranteed road to success.
    2. Overeating after fasting never occurs if the fast is long enough to allow your stomach to shrink so it simply will not hold too much food. Silly fake fasts of a few hours cause this. A fast needs to be at least a couple of days to allow your stomach to shrink. Then overeating never occurs.
    3. The only liquid to consume for a creible water-only fast is, WATER. Anything more is a scam. No exceptions.
    4. No one should fast unless they are already consuming a healthy WFPB diet.
    5. Hurray for exercise in moderation. Finally something right.
    6. Fasting MUST rule your life or you will not fast. Until you accept that truth, don’t bother.
    This author could actually do some good if she would skip the counterproductive sound bites and admonish MFP to incorporate fasting into its meal-tracking app – a defect that has been ongoing for years.

    • Avatar $323536919 says:

      the author’s work is undocumented so it sucks — your comment is undocumented so it >>>>

    • Avatar eugene perkins says:

      Salbers- According to you, if you eat meat, fasting will not work at all? The rest of what you say I am totally on board with, but why not meat?

      • Avatar Mike says:

        There is no evidence to support his claim. In fact, IF plus a ketogenic diet (lots of meat and fat) is a powerful combination.

    • Avatar Carolyn Brown says:

      I have been fasting for over a year. I didn’t fast to lose weight but I did lose about 5 lbs. I fasted because I wanted to become insulin sensitive due to type 2 diabetes in my family line. I have been at the same weight after starting to fast regardless of what I eat without counting anything. I didn’t do it gradually. I just jumped in. I was hungry and stayed nervous for about 2 weeks and after that I had no issue. I fast 5 days a week for 16 hours minimum. I find myself at 19 hours max so far depending on what’s happening at that time. I do drink black coffee in the morning as usual and water the rest of the fast. I don’t eat like I should but I do eat a lot of beans, oats, vegetables. I do love potato chips and french fries and eat them more often than I should.

    • Avatar Brian Kline says:

      Let’s just be glad that intermittent fasting is working its way into the mainstream. Also, she quoted Dr. Jason Fung AND Gin Stephens, two well respected people in the IF world. That’s helpful. Fasting is extremely healthy and I’m honestly surprised to see My Fitness Pal putting this out there because they’ve been the biggest proponent of the “eat less/move more” way of life that has NEVER worked for most people. I used their app years ago to track how many calories I take in, and according to their app I should lost a bunch of weight. It never happened. So, let’s stop harping on this author, ok? Intermittent fasting is GOOD for you.

      Also, I’ve never eaten a whole food plant based diet in my life and I fast. So your statement is inaccurate. I know quite a few people who fast, either intermittently or extended, who don’t only eat plants. So, just stop.

    • Avatar Colleen Phillips says:

      And so, what are your documented credentials in the field of fasting?

  5. Avatar '_' says:

    id like to see a scientific study to back up this claim: “Zero-calorie sweeteners still have a negative effect on insulin levels”

    zero calorie sweeteners have zero effect on insulin.

    the behavior that people over eat when consuming diet soda has nothing to do with the nutritional value of the soda.

    you may as well say that working out causes weight gain because some people will over compensate with more food after working out.

    • Avatar Brian Kline says:

      Ok, the studies are out there. Read Dr. Jason Fung’s book “The Obesity Code”. Artificial sweeteners have a well documented affect on insulin.

      • Avatar '_' says:

        the same Dr. Fung who said ” Sweeteners also do not seem to raise insulin levels.” in this article?

        I’ll leave aside the many other issues (e.g. sweeping generalizations without references) i have with how that article is written but this Dr himself says the exact same thing i was getting at. people over compensate when the drink diet soda but the scientific fact is that: zero calorie sweeteners have zero effect on insulin.

        the best thing he says in that article is “A large problem with most nutritional research is that there are often conflicting reports. One study will show a benefit and another study will show the exact opposite. Why is this? Generally, the deciding factor is who has paid for the study.”

        and that is absolutely true. its important for people to understand the studies not just parrot other peoples’ conclusions. again there are no studies that show zero calorie sweeteners are bad for you, and there has been a shit load of money thrown at big sugar’s problem of trying to prove that they are. They even tried to tell us trident gum is cancerous in their attempts to demonize zero calorie sweeteners.

        im not trying to say that diet soda is going to help everyone lose weight, but if you replace regular soda 2x per day with diet soda 2x per day and make no other change to your diet / regimen you WILL lose weight. and every doctor you ask will agree with that.

  6. Avatar catmann says:

    I started my fast by just jumping tight in too. I drink tea with almond milk and of course water, during my fasting hours, 16+, but occasionally I will drink a mug of Bone broth at night. I too started my fast as a way to help reduce my weight to avoid going over the edge into diabetes. Ive been doing it for almost a month now with no issues what so ever and have lost almost 10 pounds.

  7. Avatar christinayoung1 says:

    I do intermittent fasting all the time, and there is just so much wrong with this article. I can guarantee that Jason Fung didn’t say to eat “healthy whole grains” at the end of a fast! These are very unhealthy (the term itself is a complete oxymoron), and jack your insulin just like any other grain. One of the main purposes of fasting isn’t just autophagy, but also to let your insulin receptors heal from any pathological insulin resistance.

    And “lean meats”??? Fatty meats are far healthier, especially those high in stearic acid like beef. They promote reverse electron transport at the mitochondrial level, alleviating hunger for long periods of time (making fasting that much easier). Lean meats don’t do this.

  8. Avatar Jackie Jordan says:

    I go with the 16 hour Fast .changed my Life 8pm-12noon….

  9. Avatar Doug says:

    Interesting comments. Sad that they are not very constructive. I have done IF in the past and recently started again. This article is not the “how to” article, just some tips on what we might get wrong. It is backed by some research it appears. And while we may not agree with everything in the article it is good information to read and will trigger some to do deeper research. I don’t rely on a single article for my definitive answer. Instead, I take research from many articles, consult with my doctor, and experiment what works for me. The truest indicator of doing it right to me is my test results from my doctor, how I feel, and if I am reaching my goals.

  10. Avatar Dr. A says:

    If you read the peer-reviewed scientific literature out there, what is quoted in this article is incorrect (note: assuming that what is quoted by these authors is what they actually wrote/intended!). The majority of the literature does NOT support changes directly to insulin or appetite in response to non-nutritive sweetener intake. There ARE some endocrine changes that COULD cause alterations in insulin/glucagon signaling, but this is newer research and there’s still not enough evidence to say either way. There is evidence that some non-nutritive sweeteners may interfere with the gut microbiome and this may be a mechanism that interferes with insulin sensitivity… but again, newer research, and probably depends on many other factors in combination with non-nutritive sweetener intake.

    Also, he’s lumping non-nutritive sweeteners together, and there are many different kinds that have different chemicals and likely mechanisms of action in the body. For example, in research thus far, Stevia appears to affect the body very differently than man-made ones.

    I also will say I have not read Fung’s book… and I’m aware that there’s a LOT of research out there. When writing (especially when it’s a book that’s not peer-reviewed), you can pick and choose what you present as “evidence” to prove your points.

    Overall, you have to be careful about these kinds of blanket statements, and careful about what you believe out there in the more popular media. Don’t believe information from a single source–do your own research and make your own decisions based on a lot of good information from good, reputable sources, and peer-reviewed is best. While there are some GREAT resources in the popular media, there are also some REALLY bad ones.

    (PS: I have my PhD in Kinesiology in molecular mechanisms and teach nutrition, so do have background here)

  11. Avatar Juan Garcia says:

    “Keep the butter and coconut oil out of your coffee,” says Gin Stephens, author of “Delay, Don’t Deny: Living an Intermittent Fasting Lifestyle.” I total disagreement because I have read and experienced that the body burns fat and increases metabolism when consuming coffee with coconut oil in fasting.

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