Fasting Without Crashing?

Intermittent fasting (IF) is a time-restricted fasting method that can promote weight loss, fat loss, and metabolic benefits for general health. However, its effectiveness and sustainability vary depending on the specific protocol followed.
A clock promoting crash-free fasting.

Intermittent Fasting: What’s the truth?

Before we get to facts and fictions, let’s quickly cover:

What is Intermittent Fasting?

Intermittent Fasting (IF) is an umbrella term for various kinds of time-restricted fasting, based on a schedule. Types include:

Time-restricted IF, for example:

  • 16:8—Fast for 16 hours, eat during an 8-hour window
  • 18:6–Fast for 18 hours, eat during a 6-hour window
  • 20:4—Fast for 20 hours, eat during a 4-hour window

24hr fasting, including:

  • Eat Stop Eat—basically, take a day off from eating once a week
  • Alternate Day Fasting—a more extreme version of the above; it is what it sounds like; eat one day, fast the next, repeat

Non-fast fasting, e.g:

  • 5:2—Eat normally for 5 days, have a very reduced calorie intake (⅓ of normal intake) for the other 2 days
  • Fruit Fasting—have a small amount of fruit on “fast” days, but no other food
  • The Warrior Diet—as above, but include a small amount of non-starchy vegetables

Why IF?

While IF is perhaps most commonly undertaken as a means of fat loss or fat management (i.e., keeping fat down when it is already low), others cite different reasons, such as short term cognitive performance or long-term longevity.

But… Does it work?

Here we get into the myth-busting bit!

“IF promotes weight loss”

Mix of True and False. It can! But it also doesn’t have to. If you’re a bodybuilder who downs 4,000 calories in your 4hr eating window, you’re probably not going to lose weight! For such people, this is of course “a feature, not a bug” of IF—especially as it has been found that, in an acute study, IF did not adversely impact muscle protein synthesis.

“IF promotes fat loss, without eating less”

Broadly True. IF was found to be potentially equal to, but not necessarily better than, eating less.

“IF provides metabolic benefits for general health”

Broadly True. IF (perhaps counterintuitively) decreases the risk of insulin resistance, and also has anti-inflammatory effects, benefits a healthy gut microbiome, and promotes healthy autophagy (which as we noted in a previous edition of 10almonds, is important against both aging and cancer)

However, results vary according to which protocol you’re observing…

For what it’s worth, 16:8 is perhaps the most-studied protocol. Because such studies tend to have the eating window from midday to 8pm, this means that—going against popular wisdom—part of the advice here is basically “skip breakfast”.

“Unlike caloric restriction, IF is sustainable and healthy as a long-term protocol”

Broadly True. Of course, there’s a slight loophole here in that IF is loosely defined—technically everyone fasts while they’re sleeping, at the very least!

However, for the most commonly-studied IF method (16:8), this is generally very sustainable and healthy and for most people.

On the other hand, a more extreme method such as Alternate Day Fasting, may be trickier to sustain (even if it remains healthy to do so), because it’s been found that hunger does not decrease on fasting days—ie, the body does not “get used to it”.

The American Journal of Clinical Nutrition wrote:

❝Alternate-day fasting was feasible in nonobese subjects, and fat oxidation increased. However, hunger on fasting days did not decrease, perhaps indicating the unlikelihood of continuing this diet for extended periods of time. Adding one small meal on a fasting day may make this approach to dietary restriction more acceptable.❞

American Journal of Clinical Nutrition

“IF improves mood and cognition”

Mix of True and False (plus an honest “We Don’t Know” from researchers).

Many studies have found benefits to both mood and cognition, but in the short-term, fasting can make people “hangry” (or: “experience irritability due to low blood sugar levels”, as the scientists put it), and in the long term, it can worsen symptoms of depression for those who already experience such—although some studies have found it can help alleviate depressive symptoms.

Basically this is one where researchers typically append the words “more research is needed” to their summaries.

“Anyone can do IF”

Definitely False, unless going by the absolute broadest possible interpretation of what constitutes “Intermittent Fasting” to the point of disingenuity.

For example, if you are Type 1 Diabetic, and your blood sugars are hypo, and you wait until tomorrow to correct that, you will stand a good chance of going into a coma instead. So please don’t.

(On the other hand, IF may help achieve remission of type 2 diabetes)

Lastly, IF is broadly not recommend to children and adolescents, anyone pregnant or breastfeeding, and certain underlying health conditions not mentioned above (we’re not going to try to give an exhaustive list here, but basically, if you have a chronic health condition, we recommend you check with your doctor first).

📱 WHICH APP?

Choosing a fasting app

Thinking of giving IF a try and would like a little extra help? We’ve got you covered!

Check out: Livewire’s 7 Best Intermittent Fasting Apps of 2023

Prefer to just trust us with a recommendation?

We like BodyFast—it’s #2 on Lifewire’s list, but it has an array of pre-set plans to choose from (unlike Lifewire’s #1, Zero), and plenty of clear tracking, scheduling help, and motivational features.

Both are available on both iOS and Android:

See the BodyFast App / See the Zero App

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  • Stop Cancer 20 Years Ago

    Dr. Jenn Simmons shares vital tips on preventing cancer and inflammation, advocating for lifestyle changes and proactive health management at any age.

    Get Abreast And Keep Abreast

    This is Dr. Jenn Simmons. Her specialization is integrative oncology, as she—then a breast cancer surgeon—got breast cancer, decided the system wasn’t nearly as good from the patients’ side of things as from the doctors’ side, and took to educate herself, and now others, on how things can be better.

    What does she want us to know?

    Start now

    If you have breast cancer, the best time to start adjusting your lifestyle might be 20 years ago, but the second-best time is now. We realize our readers with breast cancer (or a history thereof) probably have indeed started already—all strength to you.

    What this means for those of us without breast cancer (or a history therof) is: start now

    Even if you don’t have a genetic risk factor, even if there’s no history of it in your family, there’s just no reason not to start now.

    Start what, you ask? Taking away its roots. And how?

    Inflammation as the root of cancer

    To oversimplify: cancer occurs because an accidentally immortal cell replicates and replicates and replicates and takes any nearby resources to keep on going. While science doesn’t know all the details of how this happens, it is a factor of genetic mutation (itself a normal process, without which evolution would be impossible), something which in turn is accelerated by damage to the DNA. The damage to the DNA? That occurs (often as not) as a result of cellular oxidation. Cellular oxidation is far from the only genotoxic thing out there, and a lot of non-food “this thing causes cancer” warnings are usually about other kinds of genotoxicity. But cellular oxidation is a big one, and it’s one that we can fight vigorously with our lifestyle.

    Because cellular oxidation and inflammation go hand-in-hand, reducing one tends to reduce the other. That’s why so often you’ll see in our Research Review Monday features, a line that goes something like:

    “and now for those things that usually come together: antioxidant, anti-inflammatory, anticancer, and anti-aging”

    So, fight inflammation now, and have a reduced risk of a lot of other woes later.

    See: How to Prevent (or Reduce) Inflammation

    Don’t settle for “normal”

    People are told, correctly but not always helpfully, such things as:

    • It’s normal to have less energy at your age
    • It’s normal to have a weaker immune system at your age
    • It’s normal to be at a higher risk of diabetes, heart disease, etc

    …and many more. And these things are true! But that doesn’t mean we have to settle for them.

    We can be all the way over on the healthy end of the distribution curve. We can do that!

    (so can everyone else, given sufficient opportunity and resources, because health is not a zero-sum game)

    If we’re going to get a cancer diagnosis, then our 60s are the decade where we’re most likely to get it. Earlier than that and the risk is extant but lower; later than that and technically the risk increases, but we probably got it already in our 60s.

    So, if we be younger than 60, then now’s a good time to prepare to hit the ground running when we get there. And if we missed that chance, then again, the second-best time is now:

    See: Focusing On Health In Our Sixties

    Fast to live

    Of course, anything can happen to anyone at any age (alas), but this is about the benefits of living a fasting lifestyle—that is to say, not just fasting for a 4-week health kick or something, but making it one’s “new normal” and just continuing it for life.

    This doesn’t mean “never eat”, of course, but it does mean “practice intermittent fasting, if you can”—something that Dr. Simmons strongly advocates.

    See: Intermittent Fasting: We Sort The Science From The Hype

    While this calls back to the previous “fight inflammation”, it deserves its own mention here as a very specific way of fighting it.

    It’s never too late

    All of the advices that go before a cancer diagnosis, continue to stand afterwards too. There is no point of “well, I already have cancer, so what’s the harm in…?”

    The harm in it after a diagnosis will be the same as the harm before. When it comes to lifestyle, preventing a cancer and preventing it from spreading are very much the same thing, which is also the same as shrinking it. Basically, if it’s anticancer, it’s anticancer, no matter whether it’s before, during, or after.

    Dr. Simmons has seen too many patients get a diagnosis, and place their lives squarely in the hands of doctors, when doctors can only do so much.

    Instead, Dr. Simmons recommends taking charge of your health as best you are able, today and onwards, no matter what. And that means two things:

    1. Knowing stuff
    2. Doing stuff

    So it becomes our responsibility (and our lifeline) to educate ourselves, and take action accordingly.

    Want to know more?

    We recently reviewed her book, and heartily recommend it:

    The Smart Woman’s Guide to Breast Cancer – by Dr. Jenn Simmons

    Enjoy!