Concerns raised about intermittent fasting

[Mercurial]

My wife recently pointed out this interview with one Matt Stone, which raises some concerns in my mind about intermittent fasting.

The short version is that daily practice of something like Fast-5 might work by constantly taxing one's adrenal glands.  This feels great while it's going on for many of the same reasons coffee does, but over time it runs the risk of taxing the adrenal glands the same way chronic use of coffee does.

Now, this offers a prediction that can be empirically tested, but I haven't been able to run the test yet.  If one has been doing IF for a while and has been eating well and getting regular rest but then abruptly switches completely off of IF (without changing diet), then there should be a crash of energy and mood.  If IF is just honestly healthier due to hormesis, then it might cause a slight feeling of sluggishness or "blah" but won't result in a crash like coming off of coffee cold-turkey would.

I haven't been able to test this yet because my personal schedule keeps having me stay up past midnight and waking up at 7am.  :p  So I need to get a few nights' good rest while intermittently fasting in order to try this.

In the meantime, though, I'd very much like to hear what this community has to say about Matt Stone's points.

[shadowfoot]

The basic tenant of hormesis is that stressors cause beneficial adaptions up to point, and after a certain intensity they cease being beneficial and can even become detrimental. For example, if you do physical work that involves your hands, you will slowly build up calluses. If you do this too fast, you will develop blisters which will take a long time to heal and will not make your skin stronger. As I am sometimes overzealous when I need to do hard labor, I am very familiar with this problem.

This is true of any stressor, be it calorie restriction, exercise, barefoot running . . . and intermittent fasting. In this way, it is very plausible that some people could overdo IF, leading to harm long term. This, however, does not imply that IF is necessarily bad.

[Todd Becker]

Mercurial, You raise legitimate concerns, but I would not worry about this.  Chronic elevation of catecholamines (and catabolic hormones in general) leads not only to overtaxing the adrenal glands, but also sensitization of receptors. However, for short periods of time, raised catecholamines have great benefits, both physiologically and cognitively.  IF gives the adrenals a rest every day by incorporating a daily "re-feed", so there should be no concern about burnout. Matt Stone himself acknowledged this in another post of his, which I think is actually a better appraisal of the situation:

http://180degreehealth.blogspot.com/2010/06/catecholamine-honeymoon.html

The oscillation of hormonal states on a diurnal schedule is perfectly normal and accords well with our evolutionary history.  The oscillation in itself is beneficial, as I wrote about in my post on Stress Oscillation.

Todd

[aelephant]

I think most of the hype about "adrenal fatigue" is just that -- HYPE.

I drink coffee regularly and can go off for weeks at a time without so much as a headache.

I took the "EC stack" (ephedrine and caffeine) for more than a month while losing almost 50 pounds on a keto diet. As far as I know, I never encountered "adrenal fatigue".

Some people might be more sensitive, but in general I think it is overblown.

Pay attention to how you feel and the results you're having, NOT what other people are telling you.

[Jbird]

Hi Everyone--As someone who has been comfortably and enthusiastically Fast-5-ing since August 2010, I just want to say that I think when people try this, it either feels right for them or not. I'm really not worried whether it's the most perfect dietary practice or not. It feels right for me and makes it much easier to maintain a weight I'm happy with. I'm cheerful, energetic, healthy, active, etc. I'm 55 but can't wrap my mind around that number, and I think people are generally surprised when I tell them my age. I think there are always reasons not to do something. There's data to support or negate just about everything. I've stopped paying so much attention to the pros and cons of various dietary practices. I actually found perusing lots of health blogs to be counter-productive, but I support what Todd is doing here. I trust Fast-5 because it intuitively feels right for me. I wouldn't try to push it on anyone, but I do encourage people to give it a try and see for themselves how they do. Most seem to find it so much easier than they expected and enthusiastically embrace it, as I have. I'm also a daily coffee drinker. I've decaffeinated myself periodically, but I always reach a point where I don't remember why I quit and go back to it. Coffee, a few pieces of sugar-free gum and an occasional Diet Coke seem to make it easier for me to go without food. I feel like I'm having "treats" and I wait till I feel hungry before chewing gum or drinking a soda and that always takes the edge off and helps me keep going. Just my experience and what works for me.

[Mercurial]

Mercurial, You raise legitimate concerns, but I would not worry about this.  Chronic elevation of catecholamines (and catabolic hormones in general) leads not only to overtaxing the adrenal glands, but also sensitization of receptors. However, for short periods of time, raised catecholamines have great benefits, both physiologically and cognitively.  IF gives the adrenals a rest every day by incorporating a daily "re-feed", so there should be no concern about burnout.

That makes sense to me.  Thanks, Todd!

[Mercurial]

Hi Everyone--As someone who has been comfortably and enthusiastically Fast-5-ing since August 2010, I just want to say that I think when people try this, it either feels right for them or not. I'm really not worried whether it's the most perfect dietary practice or not. It feels right for me and makes it much easier to maintain a weight I'm happy with.

Hi Jbird,

I get where you're coming from, and I totally relate.  I've been doing Fast-5 since the start of August 2011.  It has been wonderful!

However, I'm also aware that human intuition often makes really bad things "feel right."  Smokers' drive to smoke comes to mind.

So while I totally agree that it feels right, and if it felt wrong that would be a good reason not to do it, but since one of the big goals with IF is longevity it requires some forethought - particularly since longevity isn't on Mother Nature's list of things she cares much about after the reproductive years.

I'm cheerful, energetic, healthy, active, etc. I'm 55 but can't wrap my mind around that number, and I think people are generally surprised when I tell them my age. I think there are always reasons not to do something.

That's fantastic to hear!

I trust Fast-5 because it intuitively feels right for me. I wouldn't try to push it on anyone, but I do encourage people to give it a try and see for themselves how they do. Most seem to find it so much easier than they expected and enthusiastically embrace it, as I have.

I totally agree with your approach. 

[Jbird]

I think intuitive "feeling right" is different from a smoker's pleasurable feelings. In other words, I see a difference between feeling right and feeling good in a hedonistic sense. Feeling right includes, for me, a clear conscience. It's not guilty pleasure. I think what you're saying is it's not enough to trust one's feelings, and I agree. It's good to have scientific facts. Todd's presentation on intermittent fasting provides that, but there are so many conflicting arguments when it comes to diet that I think, in the end, one has to choose based on actual experience. My reasons for doing this have more to do with controlling blood sugar and weight than longevity. I wonder if men think more about longevity than women. I have a hunch they do. There I go with my intuition again, but I wonder if there are any studies to support that.

[Nino]

I have personally experimented with most of the diets mentioned on this site; from paleo, keto to carb cycling. I haven't practiced the fast-5 or read it's literature but I did actively follow the warrior diet for a period of 6 months beggining last spring. For those of you unfamiliar with WD, it's similar to fast-5 in that you essentially fast for 18-20 hours everyday, and restrict yourself to only eating in that 4-6 hour time frame. The founder of the warrior diet advocated "feasting" right before bed time, and specified in what order to eat protein, carbs and fats during this "feast".

At the beggining of the diet I felt amazing, I could similarly describe it as the fast-5 diet has been described on this board. I would usually workout out (running, swimming, and heavy lifting) prior to my meal, and then feast from 7-11pm. My overall strength greatly increased, while I was breaking new PR's in time and distance for both running and swimming.

While on this eating plan I often noticed that in the middle of the day I would feel a surge of energy, like drinking a giant cup of coffee. I would become more focused, energetic and genuinely positive.

I noticed no increase in bodyfat % and it made everyday more exciting because I knew at the end of the day, bounty-full feast awaited me.

But after a few months, I started to obsess about my feast meals. All I would think about all day was what I was going to eat later. I would literally rush home and start stuffing my face as fast as I could and nearly once lost a finger when I too excitedly cut up a chicken for dinner.

Before I knew it I began to cheat, I started eating two giant meals a day instead of one. Food began to occupy every thought I had. This loss of control lasted for a couple months until I moved back to LA from Boston. My Friends and family unanamously agreed that I had gotten fatter. I wasn't anywhere near obese but my body fat % had skyrocketed from where it was when I started. (I didn't take exact measurements but I can say it went from somewhere around 9% to 15%)

I then realized that this diet was no longer for me, and spent the entire  summer losing what I had gained and switching up my diet regiment.

The point of this story is to emphasize the pyschological aspect of diets like this and how easily it can go awry. I've always had exceptional self-control, until it fundamentally crumbled under this eating plan.

I put a lot of the blame on my disregard for how many calories I was eating per meal. I mistakenly assumed my body would simply tell me when to stop eating, which it did at first, but this communication slowly diminished over time.

Diets like fast-5 can be beneficial, but they require the same will power and dedication that other diets do. I completely agree that no one diet works for everyone. I believe they need to be taylored to each individuals needs and physical/mental make-up.

I'm currently on my own combination of carb cycle/stream-line metabolsim plan. I focus on eating 4-5 small meals a day and try and restrict carbs to meals either immediately prior to, or after my workouts. So far this has worked best for maintaing low body fat and getting in better shape, regulalry eating small meals throughout the day de-fantasizes food for me; and if I have any foods I want to indulge in I sync them with my workouts in controlled quantitites.

I'm curious as to whether anyone else has had such an experience with fast-5; or if anyone has engineered their own personalized eating plan that they've found beneficial.

[dnn8350]

Just a bit of reassurance on long-term IF.  At age 62, I've been fasting 20/4 for more than 10 years, and also exercise for an hour most days (mainly Heavyhands walking and running (both LSD and intervals), and bodyweight).  I feel consistently energised on this regime, and rarely feel the necessity to eat outside my usual schedule, even when on day-long hikes, bike-rides or ski-trips, etc.  My ambient heart-rate is usually around 46-48, and my resting rate typically 40-42, which I take to be some reassurance, along with normal BP, that I'm not normally under undue physiological stress.

[Todd Becker]

Just a bit of reassurance on long-term IF.  At age 62, I've been fasting 20/4 for more than 10 years, and also exercise for an hour most days (mainly Heavyhands walking and running (both LSD and intervals), and bodyweight).  I feel consistently energised on this regime, and rarely feel the necessity to eat outside my usual schedule, even when on day-long hikes, bike-rides or ski-trips, etc.  My ambient heart-rate is usually around 46-48, and my resting rate typically 40-42, which I take to be some reassurance, along with normal BP, that I'm not normally under undue physiological stress.

dnn8350,

Thanks for weighing in with your experience. I'm like you and Jbird, I find that IF is very natural and in fact becomes easier with time. In re-reading some of the posts of those (here and elsewhere) I notice that those who struggle with IF often do so with the attitude that the first meal after a fast is some kind of "reward" or excuse to indulge. That is certainly not how it works for me. While I find that fasting typically enhances the taste of food, I fill up and satiate on less food, if anything.

If someone trying IF finds themself gorging, overeating or daydreaming about food, I would take that as a sign that they are proceeding too quickly, and should process more gradually. We all adapt to new dietary or
exercise practices at different rates.

I do see some people sounding unnecessary alarm about IF. The latest is the blogger and neurosurgeon Jack Kruse who appears to think that IF is only advisable for people who are quite healthy. He has the idea that if you are leptin resistant (a very large percentage of overweight people) you absolutely must eat a high protein breakfast to achieve a "leptin reset". I've tried to follow his reasoning on this, but I'm not convinced. The fact is that for most of us breakfast is an easy meal to skip  Doing so extends the benefits of low insulin autophagy that get underway while you sleep. Why stop a good thing just when it is just getting going?

The typically circadian cycles of leptin, ghrelin and other energy hormones are in large part a conditioned social construction of Western meal schedules. I think we are versatile creatures with far less dependency on fixed meal patterns than many people realize, including the "experts".   Over a period of weeks, it is not that difficult to decondition habitual meal schedules and adapt to alternate schedules, or even the lack of a fixed schedule.

[dnn8350]

Yes, I agree that some people do perhaps try to rush into IF too quickly and consequently misinterpret their short-term response as meaning that the regime is unsuitable or unsustainable.  I progressed into IF via warrior-style eating, where I ate mainly fruit and raw veggies during the day.  This was during a period of body re-composition during which my weight dropped by around 30 pounds, and my body fat levels stabilised at around 10%.  Over time I noticed I was having to remind myself to eat the fruit and veggies, and gradually this morphed into water-fasting until the evening.  I've also noticed the change you mention in my relationship with my "break fast" meal.  For a time it did seem like a reward for abstinence, and I would sometimes stuff myself to the point where I was over-full.  This doesn't happen now - I feel a pleasurable sharpness of appetite, but it isn't overwhelming, nor do I feel any special urge to over-eat.

I suspect that there is both a physiological and a psychological component to all this.  No doubt various aspects of body chemistry need time to up-regulate or down-regulate, and one cannot truly assess one's relationship with IF until this has had time to stabilise.  But we are also programmed from childhood, by well-meaning carers, with the idea that we will weaken or even die if we don't eat on some regular, frequent schedule.  I can only think that this is the reason why so many people react with such incredulity when I tell them about IF, and vigorously attest to their own inability to go without food for more than a few hours without collapsing in a heap.  If I point out that our ancestral capability to store and release substantial amounts of energy must have evolved to cushion us against irregular feeding schedules, they often concur with the logic.  But despite this, the psychological barrier to applying it in one's own case is still powerful; I've lost count of the number of people who've self-diagnosed themselves as "hypoglycaemic", which if true, must be reaching epidemic proportions.

I guess if we persist in putting this information out there it may gradually have some effect, even (possibly) on the experts.  At least that's my excuse for occasionally boring the pants off people who challenge my "unhealthy" habits.  Meanwhile, I'm happy to continue my personal "experiment of one".