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Let me introduce myself. My name is Mark Sisson. I’m 63 years young. I live and work in Malibu, California. In a past life I was a professional marathoner and triathlete. Now my life goal is to help 100 million people get healthy. I started this blog in 2006 to empower people to take full responsibility for their own health and enjoyment of life by investigating, discussing, and critically rethinking everything we’ve assumed to be true about health and wellness...

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February 16, 2011

The Myriad Benefits of Intermittent Fasting

By Mark Sisson
527 Comments

Calorie restriction is all the rage in anti-aging circles. A few mice and worm studies seem to show that drastic reductions in food intake over a long period of time have the effect of prolonging life – although I’m not sure I’d call it living. For one, these animals are actually restricted. There’s no ad libitum access to food. They’d prefer to eat more, but are prevented from doing so. I guarantee you they’re unhappy and, if they could put (cartoonish high-pitched) voice to physiological state, would say they’re starving.

Anyway, humans have picked up on this calorie restriction stuff. You might have seen one or two CR gurus giving TED talks; the exposed rib cages, gaunt faces, and complete lack of lean muscle mass are dead giveaways. Okay – that’s a bit unfair. CR is a legitimate way to improve many health markers. I’m just not convinced actively restricting your calorie intake through sheer will is the true path to enjoyable longevity. I’d rather be robust, vibrant, and full of zest. I want to eat big strapping meals of steak and veggies smothered in butter without counting calories. On occasion, I like to devour an entire roasted chicken (yeah, yeah, chicken has more omega-6 than most animals, but I’ll live). I want to maintain muscle mass and have enough energy to go on long hikes and have the legs to still leap for high passes (over the young guys) at the end of Ultimate games. And as I appreciate the neuroprotective and autophagy-promoting qualities of calorie restriction, I’d rather not expend the mental energy and fortitude required to maintain such a regimen day-in and day-out. Nor would I willingly subject myself to forced calorie restriction, a la the lab mice. No human-sized rat cages for me, even if they include a salt lick and a running wheel (don’t get any ideas, Blaisdell). Based on the science, I don’t think all that is necessary. I’ll just IF instead.

Fasting is one way to have your cake and eat it too. Beyond the already proven benefits of a Primal Blueprint low-carb lifestyle, fasting once in a while seems to offer many of the same benefits of calorie restriction – you know, stuff like increased longevity, neuroprotection, increased insulin sensitivity, stronger resistance to stress, some cool effects on endogenous hormone production, increased mental clarity, plus more – but without the active, agonizing restriction. You just eat Primally, focusing on meat and vegetables with plenty of animal fat, and skip meals on occasion. A sixteen-hour fast is on the low-but-still-effective end (you could easily maintain a daily sixteen hour IF regimen, giving you an eight hour eating window, a la Leangains), or you could opt for longer, more intermittent fasts – say, a full twenty-four hours once or twice a week. When you’re done with the fast, eat as much as you want (which usually isn’t an issue, once you’re PB-adapted). It essentially turns into “eat when you’re hungry,” because let’s face it: eating the types of foods we evolved eating induces powerful satiety and makes eating the right amount of food a subconscious act. Fasting becomes a whole lot easier (and intuitive) when you’ve got your food quality dialed in. And I’ll come back to that little caveat at the end here.

“Fasting” was the top search term for MDA last week, and I hadn’t done a big post on it in a while, so I thought I’d do a comprehensive rundown of all the benefits (some conclusive, others prospective) you can expect to obtain from IF.

Longevity

Everyone wants to live longer, but I find longevity pointless if you’re not enjoying yourself. Otherwise, life becomes dreary. Consider the plight of the vampire – he lives a long, lonely life, never really connecting with anyone, never really enjoying all the time he has at his disposal. If the suggested longevity benefits of fasting pan out, I think we can enjoy the vampire’s longevity (and perhaps even some of his incredibly immune and restorative properties) without the downsides. Oh, and we’ll eventually have to die, but we have the option of sunbathing.

The popular c. elegans worm enjoys increased longevity with both twenty-four and forty-eight hour IFs via signaling through a gene that we all have.

One study (full PDF) from the 1940s found that varying amounts of twenty-four hour IFs (every other day, every fourth day, every eighth day, etc) prolonged the lifespan of rats without retarding or stunting the growth (as occurred with calorie restricting them). Female rats responded best to every eight day fasts, while males responded best to every other day fasts.

Reductions in brain insulin signaling have been shown to increase lifespan in animals, either by calorie restricting or actively knocking out brain insulin receptors. Fasting also reduces brain insulin signaling, at least in rats.

Blood Lipids

Going in and pharmaceutically manhandling your cholesterol synthesizing equipment is one thing; eating real food and exercising, resulting in possible alterations to your lipid profile, is another. We don’t set out to force your blood lipids into submission, but lifestyle changes that happen to change them for “the better” are usually a good thing. Fasting brings potent changes to blood lipids in an “organic” way – you’re just letting your machinery do its thing on its own – and this is probably a very good thing.

IF is as or more effective than calorie restriction in improving metabolic syndrome markers in overweight women, and it’s a whole lot easier to stick with.

Alternate day fasting improved cardiovascular risk markers, including lowered triglycerides and LDL-C numbers (although it’s unclear whether the improvements were related to the weight loss alone or something unique to fasting).

I discussed this last week, but it can’t hurt to mention that short-term alternate day fasting wrought improvements in LDL particle size and distribution in obese adults.

Compliance

A dietary regimen is useless without compliance. In fact, that’s what we’ve always said about the low-fat, low-calorie diet advice we’re inundated with: sure, they might work, but they’re impossible for most people to maintain. Eating Primally solves this problem, because it’s simple, easy, delicious, and satiating (you just have to enjoy cooking, or learn to), and IF is another compliance-breeding regimen that blends quite nicely with the PB. A lot of Primal eaters find that fasting just kinda happens without them setting out to do it, so it’s not even a conscious struggle. Check it out:

The obese (read: the ones who need the most help and often have the worst time sticking to a diet) were able to “quickly adapt” to alternate day modified fasting, which meant on fasting days they’d get 26% of their normal caloric intake. They were also able to maintain physical activity despite the fasting.

Heck, intermittent fasting even helped cocaine addicts stick to their treatment and rehab program. Not bad.

Cancer

The notion of IF reducing cancer incidence and improving survival is compelling, but little evidence in humans exists. Ketogenic diets may also offer exciting potential for cancer patients, and both IF diets and ketogenic diets share something: fat (either dietary or from your own adipose tissue) as primary fuel sources. But, while ketosis isn’t exactly desirable or optimal as a lifelong dietary regimen, IF is sustainable, simple, and can be integrated into your current diet. As of now, most of the evidence for IF’s protective effects against cancer exist in animal trials, mostly using mice. Still, fasting seems to confer so many other benefits that working it into your life for its anti-cancer potential is probably worth it. Some of the evidence:

Calorie restriction is proven to fight cancer cell proliferation in mice, but researchers found that intermittent fasting was just as effective. In fact, here’s a review of most of the animal anti-cancer evidence. It’s quite compelling.

Some researchers are speculating, based on substantial evidence, that fasting before and during cancer treatment should result in reduced morbidity, better tolerance of chemotherapies, and higher cure rates. This is refreshing news. A preliminary study in human cancer patients found that fasting during chemotherapy reduced the negative side effects of the treatment. The authors are quick to point out that the results are in no way a prescription for fasting in chemotherapy patients and that controlled trials are needed to change official recommendations, but that doesn’t mean you – the individual – can’t experiment.

Growth Hormone

Aging humans “normally” experience reductions in growth hormone. While it’s true that unchecked growth hormone can lead to unwanted cell proliferation (like, ya know, cancer), growth hormone therapy can really help stave off the doldrums of old age. Luckily, short-term fasting induces growth hormone secretion in “normal men.” I’m not for mainlining GH or anything, but I’m all for amping up my own production. Furthermore, a recent study found that resistance training actually blunted hunger for an hour. I’ve found this to be the case for me. If the body “needs” food right after a workout, why would hunger be blunted? This is why I tend to hold off on the eating post-workout. Every little bit helps, especially as you age.

Neurological Health

Fasting doesn’t cause your brain tissue to waste away, contrary to what some people will tell you. It’s actually good for brain health. Any dietary restriction tends to increase neuronal plasticity and promote neurogenesis, but it was IF that had the greatest effect (with the fewest downsides). Another study of mice found that meal frequency impacts neuronal health. That is, mice who ate larger meals more infrequently saw greater increases in brain and overall bodily health. Still another study found that IF was beneficial for peripheral nerve function in mice by promoting the maintenance of the neuronal pathways responsible for locomotor performance. It’s almost like this stuff just puts your brain in repair, or maintenance mode.

Autophagy

Fasting turns on autophagy (most studies nowadays treat this as common knowledge), which is the process by which cells recycle waste material, eliminate or downregulate wasteful processes, and repair themselves. Why is autophagy so important? It’s required to maintain muscle mass, and inhibiting it induces atrophy of adult skeletal muscle.  It reduces the negative effects of aging and reduces the incidence and progression of aging-related diseases. In fact, researchers have determined that autophagy is the essential aspect of the anti-aging mechanism of fasting. Without the autophagy that fasting provides, you would get very few of the benefits. Fasting even increases neuronal autophagy, which aids in maintaining mental health and function. Short term fasting, too. No marathon thirty-six hour fast required.

Fitness

You’ll hear that you should never exercise on an empty stomach. You’ll hear that fasted training will burn your  muscles and cause you to waste away. You’ll hear that performance will surely suffer. None of these things are necessarily true – and they are even less so if you are well-adapted adapted to a low-carb eating strategy. Fasted training can actually result in better metabolic adaptations (which mean better performance down the line), improved muscle protein synthesis, and a higher anabolic response to post-workout feeding (you’ll earn your meal and make more muscle out of it if you train on an empty stomach). Studies on Muslim athletes during Ramadan show no effect on performance while fasting, as well as better lipids in those who exercise and fast rather than just fast. When you train in a fasted state, glycogen breakdown is blunted and more fat is burnt, leaving you more glycolytic energy in the tank for when you really need it and less body fat. Those are just a sampling of the benefits to fasted training; there are dozens more. Check out Martin at LeanGains (linked above) for more information on fasted training. It’s his specialty.

Mental Well-being and Clarity

You’ve heard this “advice” before, probably from an expert dietitian in some copy-and-paste article on healthy living on Yahoo! Health. It’s the mantra of the high carb crowd: failure to eat something every few hours will cause mental fog and sluggishness, so keep a banana or a granola bar on your person at all times. Of course, this is all based on an assumption that we need to supply exogenous carbs on a regular basis to properly fuel the brain. This notion that fasting is only the province of anorexics or “those crazy caveman dieters” has kept many people from experiencing the myriad benefits.

I maintain that one’s comfort in handling IF effortlessly does increase dramatically when you’ve reprogrammed those cells (and genes) to predispose your body to derive most of your day-to-day energy from fat, as opposed to constantly dipping into glycogen stores (as happens when we rely so much on refeeding carbs every few hours). It’s also why I recommend that you eat according to the PB for at least three weeks before you really start incorporating IF on a regular basis. I’ll be discussing this detail more in upcoming posts on IF and what I am calling “the Metabolic Paradigm Shift”.

Overall, fasting just seems right. It’s like a reset button for your entire body, presumably across a large spectrum of maladies and dysfunctions. It puts your body into repair mode – at the cellular level – and it can restore normal hormonal function in the obese or overweight. Now, you don’t have to fast, but it’s definitely something to consider. As I said, I don’t plan my IFs – I let them happen. I prefer to fast when it’s forced upon me, like when I’m traveling or under a deadline. Once you’re acclimated to the Primal Blueprint diet, give it a shot and report back. Obviously, you won’t know if you’re fighting budding cancer cells or turning on autophagy in your brain, but if you can tolerate fasting and even derive some subjective benefits, those potential long-term benefits make it a worthwhile addition.

Have you tried IFing yet? Did you have a great, transcendent, middling, or perhaps even awful experience? Let me know how intermittent fasting has worked – or hasn’t – with your lifestyle in the comment section!

UPDATE: See this post on Women and Intermittent Fasting.

TAGS:  Aging, hormones

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527 Comments on "The Myriad Benefits of Intermittent Fasting"

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Robert Evans
Robert Evans
5 years 7 months ago

I suspect IF fasting combined with a paleo/LC diet is particularly helpful.

Getting a lot of fat/protein will reduce satiety. Eating a HC ‘refeed” isn’t satisfying – you’ve got to eat plates of pasta to get the same feeling.

So IF+paleo = less calories in.

And there is something to be said for stomach shrinking. Is it real — or is it just brain triggers when it thinks you are full. I suspect the brain doesn’t know right away if you’ve stuffed your tummy with high-carb bread and pasta — or fat.

Buttercup
Buttercup
5 years 7 months ago
Interesting point, re: stomach shrinking. I always assumed it had to do with insulin response overriding actual hunger cues, leading people to overeat carbs. You know, that woozy feeling after a huge plate of pancakes? But last night, I made some Primal almond flour muffins to accompany a soup, and what intrigued me was how, if I don’t eat anything remotely “bready,” my body will regulate itself and I literally cannot overeat, even if I wanted to. I feel so much more in control of my hunger cues. But with last night’s “muffins,” I felt I could go on eating… Read more »
Robert Evans
Robert Evans
5 years 7 months ago

I’ve always though the brain is quicker than your intestines. After all it would take 30-40 minutes for your stomach to clear.

But the analogy is to artificial sweeteners – if your brain think it got sugar, it is going to do something.

Carbs are low-density foods — you’d need to eat a lot of tubers as a small ancestral rodent to survive — the problem today is it is way to easy to eat them..baking them makes them taste a lot better.

Patrícia
5 years 7 months ago

And the funniest thing is that people keep on saying “oh? these vegetables of yours will not sustain you for long!”…

I think they do.
And I don’t think their breads/pastas will either…

candice
candice
4 years 4 months ago

maybe if your brain is relying on your tongue for all of it’s information…which it does not

Janet
Janet
5 years 7 months ago
I am having the same problem of over eating when I make anything “bready”. I made almond flour biscuts last night and also could have devoured them all. Just had 2 of them with egg salad today for lunch (should have just had 1!) and now am feeling very sleepy, like I used to with carbs. I am thinking these “bready” foods are too concentrated for me and not really in the true spirit of Primal. I am going to fast now until tomorrow. I haven’t fasted in a while – thanks Mark for reminding us this is a good… Read more »
Kelda
5 years 7 months ago

Check out the nutritional breakdown on almonds, they do contain carbs, if you are eating quite a large portion of these flour substitute foods you will be intaking more carbs and perhaps hence the carby after affect.

Sara
Sara
5 years 7 months ago

Would love your reciepe for Buiscuits?

Brian
Brian
4 years 9 months ago

If your feeling sleepy after you eat cooked food it is because u lack the enzymes in the food 2 break it down..ur food will sit in ur upper stomach 4 up 2 an hr before ur own enzymes kick in and start digesting the food…2 start the process of digesting cooked food immediately u need 2 take digestive enzymes and u will fell alot more energetic after u eat…u also dont allow the food 2 start rotting..try em

Dirk
Dirk
5 years 7 months ago

Don’t feel woozy after a plate of pancakes but more like porn star Traci Lords in the film “Insatiable.”

Karen
Karen
5 years 7 months ago

carbs. i’ve had to cut all grains AND nuts out of my diet. They’re not primal anyway…

nick
nick
4 years 5 months ago

Nuts are too primal, read up on Marks books and other Paleo sites, grains and BEANs are not primal/Paleo.

Kelly Fitzsimmons
3 years 8 months ago

Nuts are definitely primal.
I can’t live without my almonds!!

Alex
Alex
5 years 1 month ago
I think you feel this way because bread actually causes a certain chemical release in the brain that is highly addictive, similar to opiates. You may have heard about the study done on rats addicted to cocaine that were given the choice between coke and table sugar…guess what? They chose the sugar. Now bread has an even higher glycemic index than table sugar meaning it is converted into glucose in the body even faster giving you that instant chemical release and consequently that “woozy” feeling. This also means that bread is potentially more addictive than sugar and that is why… Read more »
Mugget
4 years 2 months ago

All those “bready” type foods cause serotonin to be released, which is basically a feel-good hormone. So the cycle goes like: eat bread > feel good > more please > eat bread > feel good…

Markus Stenemo
Markus Stenemo
4 years 4 months ago

I have been doing IF in combination with paleolithic diet for about 2,5 years, and I highly recommend it to everyone.

Mugget
4 years 2 months ago

Yes, your stomach does shrink (and also get larger) according to how much you eat.

When I wanted to put on some weight and bulk up, I would eat a bigger than usual dinner one night a week, followed the next day by a massive breakfast. The big dinner expands your stomach overnight, then you physically have more capacity to eat a larger breakfast the next morning.

That’s a trick among endomorph body type bodybuilders who have trouble eating enough.

Buttercup
Buttercup
5 years 7 months ago

I accidentally IFed for the first time this week, and felt great. No fog, no fatigue, no hunger.

But it got me thinking…how does a morning coffee or tea fit in to IF? Is that technically breaking the fast?

Aaron Blaisdell
5 years 7 months ago

The consensus seems to be that coffee if anything can assist in maintaining a fast without derailing its benefits. Same goes for consuming small amounts of fats (butter, coconut oil, cream) during the fasting window. This stuff was mentioned in one of Robb Wolf’s podcasts I think.

Keith
Keith
5 years 7 months ago

Just a quick note – Eat Stop Eat and LeanGains both follow a zero calorie fast for 24 (ESE) or 16 (LG) hours. This means no fat (all of which are high calorie)

But, yes, coffee and tea are a godsend!

nick
nick
4 years 5 months ago

I do IF and drink an Espresso/ Latte Brevea every morning and it has not hindered my results one bit.

Jim
Jim
5 years 7 months ago

I don’t see how you guys fast like this. Back in high school I would do the 30 hour famine, but that was a lot of hard work and I carried around a gallon jug of water with me and drank that constantly. I’ve only been primal for about 2 months. I don’t have to eat nearly as much, but I’m still very hungry after 6-8 hours.

Real
Real
5 years 7 months ago

When you did the 30 hour famine, your body was likely used to the SAD and nutirent starved. As soon as you stopped eating, your body wasn’t prepared to use fat stores for energy. Your hunger signaling would have been intense. Once primal, your body can use fat reserves easily and is no likely starved for actual nutrition. People eating primaly can easily do a mini-fast by accident because you are never experiencing that massive hunger.

Robert Evans
Robert Evans
5 years 7 months ago

Try turning a bit older — your appetite does go down.

Sharon
Sharon
5 years 7 months ago

I wish.

marilyn zorn
marilyn zorn
5 years 7 months ago

Not so for everyone. I will be 69 this year and my appetite is still going strong………………….

Dirk
Dirk
5 years 7 months ago

Just finished my weekly 36 hour fast with a can of organic coconut milk and some organic cacao nibs for lunch and honestly didn’t want them – food just wasn’t that appealing to me. I am looking forward to dinner however.

David
David
5 years 7 months ago

Go to leangains.com and or google Ghrelin. This is the hormone that is responsible for your hunger, the reason you feel hungry when you 1st start IF is because it appears during your normal eating times, once you have adapted (doesn’t take too long) you will find you can fast without any real hunger

Turbo Kelly
Turbo Kelly
5 years 7 months ago

I first tried IF when I was still eating a lot of carbs, and a low-fat diet. It was nearly impossible for me. Shaky, headaches, brain fog, so starving I could barely take it.

Since primal/paleo eating, it’s totally different. Last week, I also “accidentally” did it, and felt great. No brain fog, no headache, fine with energy. The only thing I’ve found is that I sometimes can’t get to sleep when I do it, and it’s not hunger pains keeping me awake, it’s like my whole body is vibrating.

bokbadok
bokbadok
5 years 7 months ago

I also have insomnia problems when I start an IF cycle. I seem to fall asleep fine, but wake up about 4-5 hours later and can’t go back to sleep. I wonder if it’s related.

Suvetar
Suvetar
5 years 5 months ago

Try to IF by having your last meal in the evening (no later than say 6 pm) the day before.

By the time you wake up next morning 12 or more hours have already passed. Then just skip breakfast. By the time lunch comes around you’ve made it to 18 hours!

TwoBuy
4 years 10 months ago

Perhaps you’re just adapting proper, pre-technology sleep patterns 🙂

http://www.lifeslittlemysteries.com/bustin-the-8-hour-sleep-myth-1362/

Melissa
Melissa
4 years 9 months ago

Insomnia is a side effect of being in ketosis. When you are fasting your body is breaking down fat into ketones and they are in your bloodstream being used as energy. I also have insomnia when I am fasting. Kind of sucks, but it’s worth it in the long run.

nick
nick
4 years 5 months ago

its because ur stomach releases grehlin based on past training of meal patterns, u have to do IF every day to get the grehlin “entrained” to the new meal pattern so it will not be released until ur meal time, and ur daytime hunger will, for the most part, go away, your body learns your habits, its like the cars that have the transmissions that learn your driving habits and adjust the shift points accordingly, pretty cool stuff.

Melissa Fritcher
5 years 7 months ago
IF was something I did naturally as a kid, before I knew anything of ‘diets’. I also stumbled back into it when doing low-carb thanks to ketosis and just plain getting my blood sugars and insulin levels in check. Having other IFers help to realize I could and should IF for health helped me ignore the advice to always eat breakfast, 6 times a day, blah blah blah. Then a genius reminded me that I always eat breakfast. We always eat breakfast, because eventually the fast has to end. I just eat breakfast at 2pm, instead of 8am. Instead of… Read more »
Uncephalized
Uncephalized
5 years 7 months ago

I’m doing the 16-off/8-on Leangains plan at the moment (and eating Primal during the 8-on part) as a way to get back into full Primality. It’s really easy, you just skip breakfast every day.

Dave, RN
Dave, RN
5 years 7 months ago

I’m doing exactly the same thing. Started about 3 weeks ago and find that it’s easy. Saves lots of time in the morning too that I spend checking on the garden and getting a few extra minutes of sleep.

“failure to eat something every few hours will cause mental fog and sluggishness, so keep a banana or a granola bar on your person at all times”.

Hard to believe there’s still people who thinks that’s true. But I guess it is if you’re eating SAD…

Walter Bushell
Walter Bushell
1 year 2 months ago

I can say if your metabolism is within a lightyear of normal, you won’t become sluggish fasting for a day or three. The human race would not be here if fasts for weeks was detrimental.

Dr. Jason Fung has fasted people for over 300 days and has taken people who were on insulin for 27+ years totally off diabetic medication. I have currently be fat fasting for over 62 hours and feel great.

J
J
5 years 7 months ago

I have been doing this method as well. Absolutely fantastic

AlliD
AlliD
5 years 7 months ago

I’ve been experimenting with the same, 16off/8on with primal eating. Its been great! I just cannot believe how NOT hungry I am. When I ate conventionally, I was always starving by lunchtime!

Jeff
Jeff
5 years 7 months ago

Ditto, it is fricken brilliant. When I first tried IFing (that sounds dirty, lol) I decided to skip night meals for some reason, that didn’t work, my body doesn’t like sleeping on an empty stomach. However, waiting until later in the day to eat my first meal feels natural, as does working out fasted.

Aneiya
Aneiya
4 years 2 months ago

I have better workouts when I haven’t eaten for a while than when eating on a regular schedule. I feel stronger, am more energized when I am done.

Aaron Blaisdell
5 years 7 months ago
The question is not IF but WHEN (When Hunger Ensues Naturally). That’s when I eat. 🙂 One of your best posts yet Mark (IMHO)! I usually eat within an 8-hour window beginning around noon and ending by about 7 or 8 pm. I am rarely hungry in the morning and I don’t often feel the need to snack between my two large meals (lunch & dinner). When I’m ill, or haven’t been getting good sleep, or am overly stressed, however, I do find I’m hungry in the morning and feel the need to nibble more throughout the day. When this… Read more »
SteverGunn
SteverGunn
5 years 7 months ago

I’m totally stealing that.. IF or WHEN. Classic.

gino
gino
5 years 7 months ago

I´m doing it Leangains style,
fasting for 16-18 (or more) hours daily and once in a week I do a easy 24 hour fast. No problem with Primal eating (I include carb refeeds 2-3 times a week pwo). It feels so good to have actually control over your own body and I´m barely hungry within the fasts although doing a lot of sports (sports student writing).

@Buttercup
No, you can have your coffee and don´t have to worry about your fasting window, it won´t affect anything 😉

GPS
5 years 7 months ago

I’m also doing Leangains and so far so good. Cutting out breakfast has made me more productive at work.
I’ve been pushing most of fasts to 20hrs or more and then hammering food when I get home…hunger wise I’m fine, but I noticed that my brain starts to lag around the 18hr mark, making me unproductive. So at that time I go to the gym to workout or just walk which seems to clear my head.

Rudolf Acquaye
Rudolf Acquaye
4 years 6 months ago

please is good we fast to boost the immune system

Rudolf Acquaye
Rudolf Acquaye
4 years 6 months ago

IT’S HELP SPIRITUALLY .

Kris
Kris
5 years 7 months ago
I wonder if anyone else shares my experience. I see quite a few primal types who say that they engage in frequent extended fasts almost without consideration, or that they eat a very small meal and it satisfies them for hours and hours. My experience is somewhat different. When I am on track and eating well (as now – going on 7 weeks!) I definitely notice that the effects of hunger are blunted. I no longer get overwhelming hunger, or headaches, or fatigue, from not eating regularly. Sometimes on weekends I’ll miss a meal because of being busy or not… Read more »
Aaron Blaisdell
5 years 7 months ago

What you’re experiencing is quite normal. Lunch is my first meal of the day (after about 16 hours sans food). I am hungry at lunchtime and typically eat a large amount. It’s my largest meal of the day. Don’t count calories, don’t worry about how much food you are eating (so long as it’s primal), and eat until you are satisfied and don’t want to eat anymore. That’s how I’ve been handling it for about two years now and it works very well for me.

Keeley Atterbury
Keeley Atterbury
5 years 7 months ago

Hi Aaron. I naturally am inclined to follow the same eating pattern, always have been. However, following CW for decades, I forced myself to eat breakfast everyday and gained weight continually wondering how this could be until finding PB. I was wondering if you find you need any longer IFs or if the daily one is enough? It is working well for me, just wondering if it is enough? Oh and I am of Blaisdell lineage as well. Are you a member of the BFNA?

Aaron Blaisdell
5 years 7 months ago

I haven’t tested your question in myself, but I suspect there are diminishing returns of longer fasts if you typically eat in an 8-hour window. I think if I’ve had a bad food week (e.g., over the holidays), a few longer fasts (~24 hours) thrown in during the month do have added benefit of returning to my normal, primal leanness.

I am not a member of the BFNA.

Catt
Catt
5 years 7 months ago

Yeah, I’m the same way. I’ve been primal for ~9 months (with no weird carb “slips” or cravings or anything, no broken metabolism, LC or VLC by accident–not design–and no weight issues) but IF for me means being hungry. I notice the fast for sure, hunger-wise.

Dave, RN
Dave, RN
5 years 7 months ago

I’ve experienced that as well. For me I narrowed it down to wanting an oral fixation or just plain “mouthertainment” while sitting at my desk at work. It’s just bordom. When I’m really busy, it doens’t enter my mind.
Like today, I’m going to the pistol range right after work for an hour, then to get a massage. I ate a noon meal, but won’t eat my dinner ’till almost 8:00PM. I know from experience now that won’t be a problem.

Liz Chalmers
5 years 7 months ago

I find that I’m hungry throughout the time that I would have been eating breakfast. Half an hour later, even though I didn’t eat breakfast, I’m no more hungry than if I had. It’s as if my stomach gives up on getting any food and quits bugging me till lunchtime 🙂

Kris
Kris
5 years 7 months ago

Good points about being busy – if I stop to think about it, that’s the key differentiator between not eating on the weekend (when I’m outside exercising or running errands or whatever) and the weekdays (when I’m standing at my desk all day with meals as a change of pace).

Certainly glad to see I’m not the only one. And Liz, I’ve noticed that behavior sometimes as well, I dunno if it’s just associated with becoming busy or if it’s the effect you describe (taming the unruly stomach!)

Harmen
Harmen
4 years 2 months ago

Hi Kris,

I think the fact that you are not overweight is the explanation of your regular hunger. For the most of us, we have a small pocket of fat storage which we can use and dampens our hunger.
An alternative explanation can be that if you know you are going to eat (socially) your body starts to prepare for it. I can have the same small cravings, but if I focus on something else I forget quickly that I wanted to eat some. The desire for food is completely gone.

packattack22
packattack22
5 years 7 months ago

I feel great doing IF but I love to have my coffee with coconut oil every morning. Mark is this sabotaging my fast?

Adam T
Adam T
5 years 7 months ago
I have been fasting for about the last month and a half. I eat dinner around 8 or 9 at night, and fast about 15 hours until noon the next day. I avoid eating breakfast except for a cup of black coffee with about 2 tbs of organic heavy whipping cream. By eating on this schedule with at least 8 hours of sleep each night, I have realized that my energy levels have increased significantly. I am increasing in body weight but, decreasing my body fat at the same based on visual results in the mirror in comparisons with pictures… Read more »
Helen Spurley
Helen Spurley
5 years 7 months ago

Very interesting! I have been considering how I might include some IF. I have been mostly primal since April, and have vastly improved health, eliminated a 6 year struggle with severe Chronic Fatique Syndrome and arthritis pain. So I have been treating my body a bit delicately, feeling my way along, but now feel ready to advance to a higher grade. Love the way you read my mind Mark!

Helen Spurley
Helen Spurley
5 years 7 months ago
Just to follow up with my post yesterday, I did my first fast today, about 19 hours. Even though I had a very light supper last night I wasn’t even slightly hungry this morning. I have been having my main meal in the morning, but realized that lately I am kind of pushing myself to eat it. So today I just had tea in the morning and didn’t eat until after 2 this afternoon. I had no problem, did not feel hungry, was alert and fully functional, but kinda sluggish by 2. Oddly, I was having more hip pain than… Read more »
salim
5 years 7 months ago

i do 3 days (non-consecutive) fasting of 20-24 hrs. I only feel hungry around 5:00 pm but then i start moving slowly for errands and do sprint workout followed by climbing trees, jumping around, shadow boxing and 20-30 minutes of basketball or soccer. My runs are the fastest i ever get, my body is so light that workout becomes awsome. Overall less eat, more energy, lean body, responsive body..i love it.

shannon
shannon
5 years 7 months ago
I’ve been struggling to lose five pounds or so for years. Involuntary fasting did it for me. I got a terrible case of the flu about two weeks ago. I was really sick for three days, during which time I had no appetite at all. I’m well now, and back at work, except for some coughing; but my appetite has stayed small for some reason, and I have lost the extra five pounds. During those days when I ate almost nothing, I discovered that it wouldn’t kill me, and now I eat smaller meals every day. It’s nice to finally… Read more »
Aaron Blaisdell
5 years 7 months ago

Nuts derailed my typical primal two-meal-a-day eating for a few months last fall, so I cut them out completely and got back on the cart. Nuts are my nemesis.

Julie
5 years 7 months ago

I’ve read glimpses of this “2-meal-a-day” eating in a few blogs recently. Is this “typical” primal? I find myself eating 3 meals and 1-2 snacks. Wondering if I’m not eating enough at my meals?

Karen
Karen
5 years 7 months ago

It sounds like you could use to increase your eats at mealtime. It’s good to give your body a break from having to digest all the time. a Primal person would not have the liberty to eat that often…

Jennifer
Jennifer
5 years 5 months ago

Do you count coconut and its primal products as nuts as well?

Timothy
5 years 7 months ago
Splendid article! Of all the primal insights, IF has been one of my favorites. I practice 20-hour fasts almost every day. No breakfast or lunch for me — it just slows me down. I can’t bear the sluggish feeling of working out with food in my system anymore. When digestion turns off, so many other systems turn on, and the magic begins! I would only add two pointers for those trying to make IF work for them: 1) When hunger becomes distracting, exercise instead. This is what I do at lunch time on fast days. It’s remarkable how 30-45 minutes… Read more »
AdrianaG
AdrianaG
5 years 7 months ago

I’m curious whether your single meal portions are “normal” or are they oversized?

Ashley North
Ashley North
5 years 7 months ago
I’ve done it a few times, every occasion was an accident-like I was kept busy all day and didn’t get a chance to think about where my next Primal meal was coming from. Every time this happened I definitely felt light, fit, energetic, and clear minded. I’ve been a bit afraid to try working out in a fasted state BUT I feel like it’s in my near future. Right now I’ve had the flu for the past 24 hours and I haven’t eaten a thing. My body refuses to want to eat anything. There must be something to that, my… Read more »
tracker
5 years 7 months ago

I’ve found since cutting the carbs out of my diet, that I’m able to skip dinner without being hungry. I don’t always do this, it just depends on whether we’ve made something for dinner, or if I feel like eating. When I do this, I typically eat lunch around 2pm, and don’t eat again until 9 or 10am the next morning.

BobChase
BobChase
5 years 7 months ago

I’ve been dipping my toe in the IF waters lately. Usually on a Monday. No breakfast or lunch then a light healthy dinner. The first week was brutal, but it’s gotten easier and honestly isn’t that bad. It’s actually gotten easier once I got my nutrition dialed-in as Rx’d here at The Apple.

Gary Deagle
5 years 7 months ago

I did daily IF for awhile, eating all my food in an 8 hour window. I have sense switched to a more random approach which I like a little better. I definitely have seen lots of benefits from IF to where I don’t foresee not practicing it.

C
C
5 years 7 months ago

My first fast was (a complete accident) and it was a noticeably effective fat loss tool. I was stranded on the road with a busted car in the middle of nowhere with hardly any money. I was a ball of stress and had zero appetite as a result, and didn’t eat (and barely slept) for at least 36 hours. I couldn’t believe how my already slim shape was even slimmer at the end of it.

Unfortunately, I broke the fast with beers.

Vidad
Vidad
5 years 7 months ago

Unfortunately? Can’t think of a better ending, honestly…

(don’t spear me, Grok!)

Jessie
Jessie
5 years 7 months ago
I started on the Primal journey 3.5 months ago and started IFing about 2 months ago. I try to be random with the IFs. Most of the time it means skipping dinner because I just don’t feel hungry at that point in my day. Most weeks I’ll IF all day Wed (from dinner Tues night until breakfast Thurs morning). A few times I’ve thrown in a Fri IF too. I find that I’m rarely hungry for breakfast on the IF days. I get a little stomach gurgly midday. Not so much hunger as rumbles. I find that those moments pass… Read more »
MichaelDaugherty
MichaelDaugherty
5 years 7 months ago
This is my first time to post. Thanks Mark for all the interesting articles and your book. I began my primal lifestyle about 7 months ago. I started at 256 and today am at 202. I have a very set eating pattern daily. 25gr of Whey Protein every morning, then 45 minutes at the gym. Moderate movement via treadmill 3 days a week, LHT twice per week. Do sprints outdoors on weekends. Lunches is salad with Tuna and a squeeze of lemon Mon. thru Fri. Every other week I do a 24 to 36 hour IF. Question: carb refeeding. I’ve… Read more »
Keith
Keith
5 years 7 months ago
I’ve been IF’ing for about a year now along with being Primal and it helped me drop 30lb’s to the lightest and leanest I’ve been since I was a kid! I typically follow Brad Pilon’s Eat Stop Eat protocol of 18-24 (+/-) once or twice a week. I’m trying to get rid of the last of my pooch, so I’ve been routinely doing twice. The first 2 or 3 times were a little rough, but since then I’ve had no problems. I actually enjoy a day or two off. It’s like a systemic do-over. IF-ing also helped re-introduce me to… Read more »
Steve
Steve
5 years 7 months ago
I’ve been doing the Eat Stop Eat method of 2 24 hour fasts per week for about 6 weeks now. Its been extremely easy to implement. I’ve been “fully” Primal since November 1st. I eat dinner one night and then don’t eat again til the next night so I’m only missing two meals. I can get a lot more done during the day not having to think about food and usually go for a walk at lunch rather than sit in the lunchroom here at work with everyone else. They all think I’m crazy anyway due to my WOE. Highly… Read more »
Legion
Legion
5 years 7 months ago

Excellent post.

Brian C F
Brian C F
5 years 7 months ago

I’ve been doing Eat Stop Eat 2x a week and the other 5 days, I go 15-16 hours between my dinner and my breakfast the next day. I have always worked out on an empty stomach. The benefit to me is when I’m not fasting, how easy it is to go for 4 or 5 hours without eating. You completely overcome that mental pang that tells you to eat every 4 hours. If you can make 15 or 24, hours what’s 4 or 6. I feel much better, and it’s surprisingly easy.

Joe
Joe
5 years 7 months ago

The only thing I don’t like about this whole fat burning, fasting, thing is that I’m not hungry nearly as much. I’m sure it’s all very healthy but I like being hungry because then I can EAT 🙂

Bodhi
Bodhi
5 years 7 months ago

I liked this blog. Since I started on the Primal Blueprint I’ve been eating between 5am and 5pm on the weekdays and between the hours of 8am to 5pm on the weekends. So I have a 12 fast every night through the week and 15 hour fast on both days of the weekend. Eating the Primal Blueprint way makes it easy to fast.

Danielle
5 years 7 months ago

I’ve been doing 15-16 hour fasts with caffeine in the morning and I think the excessive amount of caff I consume on an empty stomach may be triggering a stress response hormonally.

Have I been dumping cortisol into my bloodstream? Yikes. So I’m backing off the caff a bit.

If today is any indication, IF-ing works just fine without it!

hawxhulc
hawxhulc
5 years 7 months ago

I’ve been experimenting with IF for the past few weeks (mainly when I’m too lazy to pack lunch and don’t have access to good food) and I’ve noticed a myriad benefits. Good post, it’s inspired me to keep it up.

Also, props for using one of my favorite words, myriad, correctly! woo!

denise
denise
5 years 7 months ago
I’m sure this has been said a LOT before, but for people with a history of ED, IFing can be very “dangerous”. There is an element of semantics in this. I suppose I “IF” daily (16+ hours) because I eat dinner early-ish and don’t eat again til about 1pm the next day. BUT I do NOT call it IF. I just don’t eat because I am not hungry or because I cannot eat before I work out. If I called it IF even to myself, i think I could reawaken behaviours that I am happy to say being primal is… Read more »
Sarah
Sarah
5 years 7 months ago
Thank you for commenting on this, as its something I’ve noticed as well. I feel that even new PBers now feel pressured (and are encouraged) to IF even if it could be harmful rather than beneficial in their individual cases. There’s almost a competitive undertone on the forums… Which I dislike. I find that skipping a meal every once in a while helps to reset my hunger cues, but if I do it too often or start over thinking it, it brings up the whole ED nightmare again. Everyone simply needs to listen to their own body and be mindful… Read more »
K.J.
K.J.
5 years 7 months ago

Thanks Denise! Eating Primally has freed me for the first time in 3 decades from the old behaviors of my ED. It started when I was 6 and though I was “cured” at 28, those obsessive behaviors have lingered. I find it much easier mentally to focus on eating when I’m hungry, eating till I’m full and not focusing on how long it’s been between meals. I can’t call it IF and I certainly would never do a planned fast for fear of overdoing:”If 16 hours is good, I’ll do 20, it’ll be better”

keithallenlaw
5 years 7 months ago

ED??? I googled and googled and can’t find it. Sorry.

Vanessa
Vanessa
5 years 7 months ago

ED = eating disorder.

Took me a while to get it too.

keithallenlaw
5 years 7 months ago

HA! Now me feels silly. Thanks partner!

Anne Lawrence
5 years 7 months ago

I thought ED was erectile disfunction, which seemed not to make sense…

Molly
Molly
5 years 7 months ago

I agree totally! As a person with a history of ED I don’t think that I could tell myself that “fasting” was good for me. I think that I would end up taking it too far. Sometimes I don’t eat a meal; typically lunch, but it’s because I am on the go and not because I am telling myself not to eat.

Lisa
Lisa
5 years 7 months ago
While I agree with the warning of treading lightly with IF if you have a history of EDs, for me this way of eating has helped mine tremendously. I find that I’ve learned to be in touch with my hunger and eat when I’m truly hungry vs. every 3 hours, or at noon because it’s lunch time or breakfast because it sets the metabolic state for the entire day, etc. While I still have a great deal of weight to lose, I found almost immediately that eating this way has really set me free from a life-long struggle from eating… Read more »
Nomad
Nomad
5 years 7 months ago
Whenever I try to figure out if something makes sense I don’t listen so much to what the “experts” say now but I think to myself, okay is it realistic of humans throughout time? For example, the common opinion that we need three meals a day. Throughout history did humans wake up in the morning and have food immediately available, and then a few hours later, more food, and then a few hours later more food…and the answer is no. I don’t think we need the amount of food we are programmed to believe we do. And to those who… Read more »
Liz
Liz
5 years 7 months ago

HAHA! That’s hysterical! But so true! I have been asking myself that same question of “does it make sense from an evolutionary perspective?” a lot lately. It’s funny how many of the paleo eaters I know are still stuck on the 5-6 meals per day eating plan.

beth
beth
5 years 7 months ago
My husband and I used to fast often when we were both carb eaters and it was always very difficult. Since I went totally primal 6 months ago the last time I fasted i had to actually remind myself that i needed to start eating again about 30 hours into it. I love tha now if I have to work late and don’t have any food with me for dinner I am not running all over the floor looking for something to eat because i’m “starving” and when i find my self just missing dinner and working late I tend… Read more »
Mary Anne
Mary Anne
5 years 7 months ago

My experience is IF just happens. Since I reduced carb intake and cut out grains, I fill up on protein and vegetables and don’t have the “gimme something more to eat” cravings like I used to. If I slip up and get some grains (am pretty sure I’ll be able to not do the 20% of the 80/20 Primal thing soon) all bets are off. I firmly believe this has to do with my body getting cranky that it is getting ‘filler’ (hmmm, but it doesn’t actually fill me up), rather than satiating protein and filling vegetables. Just MHO.

Ed
Ed
5 years 7 months ago

Monday thru Friday I go 22 to 23 hours in a fasted state and have a 1 or 2 hour window, usually around 6 pm….to eat a very large and satisfying primal meal. Then on the weekends I simply eat (primal) when I feel like it. It works great for me. Energy is high and it is extremely liberating, NOT having to think about ‘when’ I’m eating next. Plus, by changing it up on the weekends, your body has to adapt and fat burning is even more intensified!! Fasting is water only.

Wafaa
Wafaa
5 years 7 months ago

I have to say, I did the whole Ramadan fasting thing in Arizona last summer. No food or water from sunrise to sundown for a month. If it weren’t for the paleo diet, I probably wouldn’t have pulled it off. Long summer days and 100F plus weather. For some reason, once I switched to paleo, I could last easily without getting as thirsty or tired during the day.

Walter Bushell
Walter Bushell
1 year 2 months ago

Ramadan fasting is not really fasting, except for the no water during the day.

From 6 AM to 6 PM is 12 hours just a normal dinner to breakfast break. Not unusual even in baseline American culture.

And Muslims probably celebrate with big meals after sundown and before sunrise.

steve mcdonald
steve mcdonald
5 years 7 months ago

Since going primal last November I’ve found I don’t have to closely monitoring when I last ate before working out. I’ve dabbled in IF but only on a meal-by-meal basis but have been contemplating expanding it to a full day now and then, possibly moving to one day a week down the road

Simon M
Simon M
5 years 7 months ago
At work today someone said they had to fast for a blood test and that they wouldn’t be able to eat until 9:30am (after the test). He said how awful this was going to be and how he might faint form a lack of calories! I then said that I regularly fasted for 16-20hrs, at which point there were deep sighs and looks of pity from my colleagues. I quite enjoy fasting and find that exercising while fasted is great. I’ve started following Mark’s recent advice to try fasting after exercise as well as beforehand and didn’t feel any affects… Read more »
Chris
Chris
5 years 7 months ago
After being primal for about a year with good results (loss of 35 lb, increased health and athletic performance), I had reached what I thought was a good baseline of fitness. However I started reading about IF in the fall, and in January started experimenting with it a bit. Right now I’m doing a 16-18 hour fast 3 times a week (Sunday night to Monday, Tuesday night to Wednesday, and Thursday night to Friday). I have definitely become leaner while maintaining strength and mass (I have lost an inch off my waist, but only dropped 2-3 lbs). I haven’t experienced… Read more »
Jeffery
5 years 7 months ago

My wife and I have been doing fasts every Monday, which makes for a really productive start to the week. We usually do some strength training as well on that day. I personally feel like crap if I try a met-con style workout while fasted.

Cara
5 years 7 months ago

I’m pretty skinny and am trying to gain weight (follow Paleo diet and can’t handle dairy)… don’t think fasting is for me. It feels like I’m always fasting since being Paleo. Am I doing something wrong? I have a high metabolism and am constantly playing catch-up with the amount of carbs and fats I’m eating (trying to balance it with protein). Any tips?

Danielle
5 years 7 months ago

Cara, I’m certainly not an expert but you may be one of those lucky girls who can get away with more a bit more carbs and a few more meals.

Go enjoy a sweet potato!

🙂

Cara
5 years 7 months ago

I have sweet potatoes 2-3x a week if not more! that’s the thing, i’m eating starchy tubers. there’s a point where you’re too skinny and i might be there… it’s uncomfortable when people think you have an eating disorder. anyway, a few tweaks here and there should do it. i’m eating fatty meats (just had pork belly tonight, delicious). thanks for your tips!

keithallenlaw
5 years 7 months ago

Don’t stress on skinny. As long as you feel good so what. Some guys, like myself, are very attracted to skinny
women. Best wishes.

jennifer
jennifer
5 years 7 months ago

how often do you work out? some strength trainging excercises should help. If you don’t have much body fat builing muscle will help you appear a little bigger and healthier 🙂
I deal with the same thing, so I can relate. Thanks for the post.
ps, i make my non primal husband lots of almond flour treats, which adds to fat.

Phil
Phil
5 years 7 months ago
I expect some others could give you some more particular thoughts,Cara, but assuming you eat a good amount of protein, how about upping your fats? How long have you been eating low carb? If not long, it might take some adjustment as your metabolism shifts to fat-burning mode. Just help it along with more fats. Slap butter on stuff 😉 Also, I think fermented foods are great.I don’t know how much they feature in Paleo, because while I know the basics of low carb, I’m not sure on specifics. But things like sauerkraut. And I drink milk kefir as well… Read more »
Phil
Phil
5 years 7 months ago

Ah, “Primal” as contrasted with Paleo(?) does some dairy, I gather.

Cara
5 years 7 months ago

I wish I could eat primal, but notice side effects from cheese… that’s the only difference for me. I eat butter and handle that ok but no milk, cheese, yogurt.

Dan
5 years 7 months ago

Cara – have you tried Raw Milk? Assuming you can find any in your neck of the woods… Google: Eat Wild.org

Cara
5 years 7 months ago

thank you! this is really helpful. i love fermented foods, crave them in fact, so perhaps my body’s telling me to go for it. am big on kombucha but will try kefir. sorry to stray from topic but i might be speaking for some people who feel they’re too thin eating this way!

thanks guys, i appreciate it. great post mark!

Phil
Phil
5 years 7 months ago

Cool, hope it works out for you. 🙂

Shelly
Shelly
5 years 7 months ago

It’s a good topic to bring up! My husband is very naturally lean and he doesn’t feel good without a lot of carbs, but it’s really difficult to get a lot of carbs just from starchy tubers. He’d have to eat them all day and that’s difficult and unappealing for him.

He’s had better results following a more “perfect health diet” route and including white rice to up his starch intake. If you’re not sensitive to rice, that might be something to consider.

Joe
Joe
5 years 7 months ago

Great post. I have recently gotten into the idea of IF, though I have found that, like stated above, it kind of just happens on its own. There was a post about a month ago that said, “Today, you’re going to skip your next meal. I took this as a personal challenge from Mark, and never looked back. I usually don’t eat till around lunch, and usually don’t even notice it. It works wonders in shedding unwanted body fat, while really clearing my head. If you haven’t tried it yet, well, what are you waiting for.

M Miller
M Miller
5 years 7 months ago

I fast on Mondays (no food between Sunday night and Tuesday morning), but I always have trouble sleeping on Monday nights. Anyone else experience this? Perhaps the problem is that I do drink some coffee (no more than other days) which may be more potent without food in my system?

Phil
Phil
5 years 7 months ago

Interesting stuff. Thanks.

Adam
Adam
5 years 7 months ago
Ironically I just started IFing last week. I do 2 24 hour fasts. One on Mondays and one on Thursdays (I stop eating at around 6-7 the night before and then start eating again the next evening at 6-7). I was a little scared at first that I’d be overly hungry, but after going Primal a year ago it’s really not that bad. It was actually quite easy. At this point in my life I really don’t care about losing weight (I went from 208 last year down to 175 due to going Primal, and that was in a matter… Read more »
Josea
5 years 7 months ago

Eating protein, fat and low carb vegetable ONLY when one is hungery will most likely result in reduced calories compared with what most people eat. That would result in ‘calorie restriction’ without trying.

mary titus
mary titus
5 years 7 months ago
I fast on a daily basis. Actually we all fast…what I do is I do not eat my first meal of the day, or my fast-breaking meal, until 3:00. Sometimes I eat later. Eating at 3:00 opens up my 4 hour “feasting” window. When I eat later than 3:00, I eat just one meal for the day. The only reason eating 3 -4 square meals a day plus in-between snacks seem necessary is that is what we’ve been taught. I am pre-diabetic and my blood glucose levels rarely go above 100. Now that being said, my glucose levels are usually… Read more »
Marni
Marni
3 years 6 months ago

That sounds like a great idea all around. I might have to give it a shot – I’m quite a foodie I’m afraid, but the problem is that I can be fairly mindless about it, even being primal. Having a time window seems like a good idea.

Nicky Spur
5 years 7 months ago

I can definitely relate to the increased mental clarity upon fasting. I find that after about six to nine hours of IF I get way more alert and rise into a state of much more relaxed awareness. Only thing is I tend to binge hard on the next actual meal I eat.

tuscany
tuscany
5 years 7 months ago

don’t we all kind of IF anyway? if we eat dinner/last snack at 8.00, then eat breakfast next am at 8.00, that’s 12 hours right there. Not that far from 16 hours IF? what is so speacial with 16 hours vs 12?

Darlena
Darlena
5 years 7 months ago

I eat breakfast and lunch and IF until breakfast again. From reading these comments (and others on IFing) everyone skips breakfast and eats lunch/dinner. Is there a reason that this is the pattern and not breakfast/lunch skipping dinner?

Uncephalized
Uncephalized
5 years 7 months ago

I would venture to guess it’s that most people like to go to bed on a full stomach. That’s why for me anyway.

jennifer
jennifer
5 years 7 months ago

i am wondering the same thing. is it really considered fasting as your sleeping?
i skip breakfast most days, but i never considered myself an IF.

i also have a question…i was talking with a nonprimal coworker about this and she mention some about your body going into “starvation” mode when you skip meals. I realize this is CW but I’m just wondering what your thoughts are on this and why its made to sound as a bad thing.

Meg
Meg
5 years 7 months ago

I’m recovering from an eating disorder. I like the idea of IF but whenever I do it my eating disorder seems to re-ignite and be fueled by my hunger (which I can’t stop). I’m lean 13.5% BF 31 yrold female. Is there any way I could incorporate IFing into my healing process?

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