
Jason Fung explains why intermittent fasting diets work - prostoalex
https://qz.com/1419105/a-diet-guru-explains-why-you-should-eat-dinner-at-2pm/
======
mancerayder
Having gone back and forth on this (a 16-hour fast for a several week period
more than one time), and having read a bunch on the topic, I've concluded thus
far that, fundamentally, there's no one-size-fits-all for human bodies. In
other words, human bodies are so complex that results for almost any food
program vary a lot.

Aside from the individual factors, which include your gender and age and
whatever uniqueness about your body that we don't know yet (like effects of
gut flora on metabolism), there's the type of exercise you do.

If you do long distance running or cycling, at one extreme, it's obviously a
no-go. If you do a short conditioning workout or strength workout right before
breaking your fast (if you're lucky enough to have a schedule that allows
that), that sounds okay.

There's some speculation that fasting 'resets' the gut flora, or that there's
a benefit to 'giving the digestive system a rest', then there's some science
around the impact on fasting on circadian rhythm reset benefits, some other
science around fasting to 'reset the immune system.'

My personal experience was that I didn't get much benefit in terms of body fat
cutting, I didn't notice a performance increase or decrease in the gym (where
I do strength training and calisthenics primarily with a bit of cardio). I DID
notice I was obsessing over food in the mornings and when 2pm came around,
there was a feeling of accomplishment.

I'm not sure it was worth it for me. As for everyone else, the jury's still
out. It's just that I'm not convinced it'll be back within my lifetime in this
complex area of study.

~~~
foldr
>If you do long distance running or cycling, at one extreme, it's obviously a
no-go.

This isn't obvious to me. I don't run seriously, but I don't find that fasting
has any adverse effect on my performance. If you are talking about running a
marathon or something like that, then sure, but hardly anyone is doing
exercise that intense multiple times a week, so you could still have fast
days.

16 hours really isn't a very long time to go without food. Your body can cope
with it fine, even if you're doing quite intense exercise.

~~~
scott_s
I imagine that if you're training for an endurance-based competition, getting
all of your required calories in one sitting once a day will either not happen
reliably, or be _really_ uncomfortable.

~~~
gamblor956
There's a lot of calorie in fats and sugars. It's quite easy to eat a single
meal at some place like Carls Jr or Burger King and meet your calorie needs
for the day of a run...and then some. If you eat at Cheesecake Factory, it's
hard to find a meal which wouldn't satisfy your calorie needs for an several
days.

------
ccmonnett
My experience with time-restricted eating has been that, regardless of the
benefits of the fasting itself (which FWIW I do believe in), it has brought
one significant change into my life: caring much more about the nutrition of
each meal I eat.

Before I began fasting, I found myself saying things like, "Well, this isn't
great for me, but it'll be filling for a few hours and then I'll eat something
else." With IF that is not an option, and it forced me to more carefully
consider whether I was providing my body with the proper fuel for the next X
hours.

Similarly, coming out of the fast, I was much more likely to eat
nutritionally-valuable foods because I knew that whatever I put in my body it
would immediately consume for fuel and I wanted to give it something valuable.

That in itself has led me to rave about IF to anyone who is interested enough
to listen. I recommend at least an experiment with it to experience that
consideration of nutrition, because I think that will stay with you whether
you stick with IF or not.

------
gremlinsinc
I'm 485. I had gastric sleeve surgery in 2012 at 650 (after losing 40 through
liquid diet).

5 weeks ago I was 515. I started a fitness challenge at a CrossFit gym, I
workout 4 days a week, I eat Keto, and I (sometimes) eat just one meal a day.
I find it really hard, like extremely hard when doing IF to get all my protein
in for the day.

I kid you not, because of my stomach size, the keto effects (lower hunger),
and only having an hour or two window for food when I stick to IF completely I
can't get more than 50 protein, and 600 calories.

This week, I've modified it to fit my body, I've added body fortress protein
which 1 scoop in almond milk = 8 carbs, and 60 protein (my daily minimum). I
eat this around 11 or noon. Then I try to have my 1 meal at 5pm. Is it IF? Not
completely, but I feel for me it works a lot better.

I can probably still get only 600-800 calories a day; example: 2 burgers +
1/4th cup cheese and a dab of mayo and I'm stuffed to capacity, it takes an
entire hour to finish this much food, but at my weight that's no biggie, the
biggest thing is getting protein so my weight lifting at CrossFit has good
results.

I'm no expert on physiology, so if anyone has tips to maximize my progress
(I'm about losing more (fat) and gaining more(muscle) as fast as humanly
possible).

Physically I feel like a million dollars, depression is mostly gone and
anxiety as well. I'm a little obsessed on my diet/exercise regime, not sure
that's bad. I started taking Vyvanse for ADHD so that also curbs
appetite/hunger and has helped me focus more on my code/work. Last year I had
major depression with dark thoughts, this year I feel like a different person,
I'm also seeing a therapist for that stuff as of a few months ago.

~~~
lawn
Because you've had that surgery and your stomach size maybe intermediate
fasting isn't the best way for you in the end?

Instead a high fat low carb diet where you really minimize carb intake (and
obviously avoid all things sugary). You can get the same keto effects if you
follow this approach.

This way you can easily eat several times a day and get all protein and
calories you need.

Of course you can mix and match IF with this as well.

> I'm a little obsessed on my diet/exercise regime, not sure that's bad.

Be mindful. Obsessions always lie at the edge of turning bad.

Also if you've only done this 5 weeks it's easy to do too much too soon and if
a time comes when you can't hold the same extreme tempo you risk a crash. This
has happened to me many times. For example I've started a new training form
and I train it a _lot_. But then I don't have the same drive like last week
and a miss a single training. Then another one and suddenly I haven't trained
for a month.

~~~
gremlinsinc
Thanks for the advice.. I think I'll keep trying this diet regime for a little
bit, I like how I feel w/ it...

Definitely see your point w/ obsessions... I over analyze and think things. I
also try to optimize everything as a developer that's just what I do lol..

I do have a fear that as winter comes I might slack off more on workouts, esp
since my gym is 30 mins away (I live in podunkville,UT), so increment weather
could affect my sojourn to the city to workout. I'm hoping I just let things
go more, and it just becomes part of my life, at least till I hit my goals.

------
koube
I suspect there's no objective way to discuss a topic while it's in the hype
cycle. Mindnfulness meditation seems to have dubious benefits, the uberman
sleep cycle has all but disappeared, but during _their_ hype cycles there was
no way to sit down and discuss whether they actually do anything. There were
too many people singing praises and making tons of claims, and there's really
no way to dispute them. The science seems to never happen on these types of
things as well, so just waiting doesn't seem to be the answer either.

~~~
jklinger410
For all we've done in science, it seems like we still have a huge correlation
!= causation issue.

I just had someone tell me that the amount of auto accidents increase between
2 and 4pm in the US. This somehow showed that people make poor decisions
during that time because of our sleep cycles? I was met with much resistance
when I pointed out that there are fundamentally different people driving
during 2 and 4pm than 8am or 5-6pm. The numbers don't lie, right? Just how you
read them...

Anyway, I'd love to see the science that mindfulness and meditation have
dubious benefits. I am such a believer in those practices, I have a hard time
understanding the argument that they are not beneficial.

~~~
koube
[https://www.scientificamerican.com/article/wheres-the-
proof-...](https://www.scientificamerican.com/article/wheres-the-proof-that-
mindfulness-meditation-works1/)

> The new paper cites a 2015 review published in American Psychologist
> reporting that only around 9 percent of research into mindfulness-based
> interventions has been tested in clinical trials that included a control
> group. The authors also point to multiple large placebo-controlled meta-
> analyses concluding that mindfulness practices have often produced
> unimpressive results. A 2014 review of 47 meditation trials, collectively
> including over 3,500 participants, found essentially no evidence for
> benefits related to enhancing attention, curtailing substance abuse, aiding
> sleep or controlling weight.

> Van Dam acknowledges that some good evidence does support mindfulness. The
> 2014 analysis found meditation and mindfulness may provide modest benefits
> in anxiety, depression and pain. He also cites a 2013 review published in
> Clinical Psychology Review for mindfulness-based therapy that found similar
> results. “The intention and scope of this review is welcome—it is looking to
> introduce rigor and balance into this emerging new field,” says Willem
> Kuyken, a professor of psychiatry at the University of Oxford in England,
> who was not involved in research for the new report. “There are many areas
> where mindfulness-based programs seem to be acceptable and promising, but
> larger-scale randomized, rigorous trials are needed.”

>As Van Dam and his co-authors wrote, “[there is] neither one universally
accepted technical definition of ‘mindfulness’ nor any broad agreement about
detailed aspects of the underlying concept to which it refers.”

~~~
erikpukinskis
That’s not evidence. By your logic I could disprove general relativity just by
doing bunch of flawed studies on the subject.

~~~
koube
I didn't say it was evidence, I said "Mindnfulness meditation seems to have
dubious benefits", and the quoted article outlines specifically the lack of
evidence around the benefits of meditation. I'm perfectly comfortable standing
by this conclusion from the lack of evidence as outlined in the quoted text.

------
peterwwillis
Intermittent fasting seems like it'd wreck your body if you do moderate to
intense exercise. So I just fasted, and now I want to do intense cardio....
but I might run out of glycogen or blood sugar. Or I may do a set of weight
lifting, but not if I can't eat protein after. So if I do intermittent
fasting, I have to come up with a complex schedule to follow in order to get
any performance gains.

The whole point of a diet is to be healthy. You don't _need_ intermittent
fasting to be healthy. It seems to just introduce complication for a menial
improvement in a few measures of health. I'm sure they _work_ , if you can
actually stick to them, but there's a lot _simpler_ diets that will also work.

Exercise three times a week. Eat lots of plants. Keep your fat, protein, and
simple carb levels within reasonable limits for your age, height and sex.
That's not super complicated to follow, and it can fit into basically any
schedule.

~~~
rthomas6
Nah, that's complete BS. Fasting doesn't impair you to the degree you're
implying. It takes a good 24 hours to run out of liver glycogen, and even then
it's not like you keel over, you just have maybe 85% of non-glycogen-depleted
performance. Just have a meal at some point the day before your workout, and
you'll be good to go. Blood sugar is also a non-issue when fasting. It is in
fact more stable in a fasted state due to very steady insulin levels. Humans
are not fragile creatures that need to eat every X hours to do physical tasks.

I do heavy weight lifting in the early morning and fast every day until 2 PM.
You don't need to eat protein right after you lift weights, later in the day
is perfectly fine. For you _optimal_ gains, maybe, but for gains, no. But I'm
not a world-class athlete, I'm a 31 year old with an office job. Intermittent
fasting is very popular in the weight lifting world, and it works very well.
In my experience, lifting in a fasted state impacts my performance 0%.

~~~
curun1r
> lifting in a fasted state impacts my performance 0%

Based on my own experiences, I'd actually expect performance to improve since
the body isn't using resources for digestion. I'm not a weight lifter, but I
know bicycling is significantly harder shortly after eating and my other
current sport, freediving, is much, much easier after fasting (my static hold
time is close to 2 minutes longer when I haven't eaten in the past ~12 hours).

One interesting observation I've had from freediving is that some of the
signals we get from our bodies are far less urgent than we tend to experience
them. The main one, in that sport, is the urge to breathe and it's actually
not an indication that the body needs oxygen. It is, instead, an indication
that CO2 is building up and you can expell it by breathing. Freedivers learn
to experience that sensation and push past it.

I'd imagine hunger is very similar. People accustomed to eating whenever
they're hungry will panic an experience "low blood sugar" when they don't
immediately respond. But we know that humans can go weeks without eating
before we die. Pushing past our accustomed non-resistence to hunger will
likely be uncomfortable, at first, and then become normal with practice.

~~~
maxxxxx
"I'd imagine hunger is very similar. People accustomed to eating whenever
they're hungry will panic an experience "low blood sugar" when they don't
immediately respond. But we know that humans can go weeks without eating
before we die. Pushing past our accustomed non-resistence to hunger will
likely be uncomfortable, at first, and then become normal with practice.

"

Exactly. People are way too used to eating all the time.

------
tzs
As always for this kind of article, some of the comments have turned to more
general discussion of human diet and metabolism. There was an very interesting
article relevant to that in Vox.com a little over a month ago [1]:

"What I learned about weight loss from spending a day inside a metabolic
chamber"

[1] [https://www.vox.com/2018/9/4/17486110/metabolism-diet-
fast-w...](https://www.vox.com/2018/9/4/17486110/metabolism-diet-fast-weight-
loss)

~~~
socalnate1
Thanks for sharing; really enjoyed this.

------
ngngngng
I dislike articles like this as they continue to perpetuate the belief that
there are secrets to weight loss. There are no secrets to weight loss. Eat
fewer calories than you burn. It doesn't matter if that involves keto, or
vegan, or one meal a day. Thyroid problems also don't change physics.

The problem is made worse because overweight people typically greatly
underestimate how much they eat, while underweight people (me most of my life)
typically greatly overestimate how much we eat. It's nearly impossible to
accurately gauge calorie intake without strict calorie counting.

When talking nutrition with people, I'll often bring up the examine.com piece
on "does metabolism vary between two people?"(1) And I am always amazed to
find at least one person in any conversation that will flat out deny the
information presented there. they are positive that if they ate one single
slice of pizza a day and nothing else, they would still be fat.

1: [https://examine.com/nutrition/does-metabolism-vary-
between-t...](https://examine.com/nutrition/does-metabolism-vary-between-two-
people/)

~~~
electrograv
_> There are no secrets to weight loss. Eat fewer calories than you burn. It
doesn't matter if that involves keto, or vegan, or one meal a day. Thyroid
problems also don't change physics._

That's like saying _" There are no secrets to space flight: For every action,
there is an equal and opposite reaction. It doesn't matter if that involves
Hydrogen, Hydrazine, or just big tubs of water -- throw them one way, and
you'll move the opposite. Your choice of fuel doesn't change physics."_

Of course fundamental physics laws hold. But some fuels and systems of using
those fuels are more effective than others.

When it comes to diet, different foods and eating patterns do have different
effects on our endocrine system, and that does affect how viably we can
sustain ourselves on less calories. Different foods will also have different
proportions that are retained vs passed the same day.

Unless you also capture ALL your own human waste, and measure it in a 'bomb
calorimeter', counting calories (intake only) is not nearly as useful as you
seem to think. If you disagree, drink 2000 calories of olive oil every day and
eat nothing else, then come back after a year and tell me that calories are
all that matter :) Disclaimer: Don't actually do that, because you would
starve to death.

~~~
goostavos
I always see this response in these threads and get a little frustrated. I
feel like it purposefully misses the forest for the trees a bit.

Sure, at a super granular level, different foods affect you differently,
trigger different biological responses, etc.. etc.. but if you zoom out, the
details just don't matter. If you're under calories, the weight will come off.

Nobody is suggesting to "drink olive oil." you can keep you normal diet, just
eat less of it, and magic will happen.

~~~
base698
If you eat a 16 to 20 oz ribeye (1200 calories) in the morning you won't want
to eat until at least dinner time. If you eat 3 donuts (1200 calories), you'll
be ravenous by noon. What you eat effects when you want to eat and how much
dramatically. Why run against a headwind?

~~~
goostavos
Oh boy, I regret commenting in this thread.

I feel like people keep either inventing things to argue against (olive oil)
or bringing up scenarios that are purposefully missing the overall point of
what people are actually saying.

Again, sure, if you zoom in, eating donuts is probably a bad strategy because
you'll be hungry again, and thus eat more calories. But in the grand scheme of
things, you CAN eat a donut if you remain below you calories. That is all
people are saying. Nothing more. Nothing less.

fwiw, we weight lifters regularly put this into practice. Bulking? add more
food. Cutting? less food.

Yes, there are details (gotta hit those macros!), but overall, the strategy
boils down to calories in/out.

~~~
jdminhbg
This is basically the equivalent of the "why does it matter what programming
language you pick as long as it's Turing complete, which means you can do
anything with it" argument. Losing weight by eating a donut and starving
yourself is like writing a web application in brainfuck.

~~~
zbentley
Not at all. It's like saying "it doesn't matter what programming language you
pick, the computer is still only going to execute the code you told it to".

Neither the GP, nor the original root of this thread are proposing that food
_choices_ are automatic, obvious, or don't have bearing on your
weight/happiness/whatever; they're saying that food _quantities_ (in calories)
are the primary determinant of how much you weigh.

That's it. Narrow ruling, specific point; no "why don't you just"-ism or
anything of the sort--or if it's there, I'm not seeing it.

------
louprado
Given that poor sleep quality exacerbates insulin resistance, it is possible
that by not eating late into the day, the research subjects in the article's
fasting study may have also lost weight because their sleep improved.[1]

Personally if I eat dinner after 5PM, I have trouble sleeping.

[1]
[https://www.ncbi.nlm.nih.gov/pubmed/21950773](https://www.ncbi.nlm.nih.gov/pubmed/21950773)

------
rawland
My question in this article is: What were the properties of the participants
in this study?

According to the paper these "eight overweight men with prediabetes [...] had
a mean BMI of 32.2 ± 4.4 kg/m2" (page 3).

The metabolism of these people is quite different compared to a healthy human.
These were sick people. And they received a strictly controlled and monitored
diet according to the paper.

Paper mentioned in article:
[https://www.ncbi.nlm.nih.gov/pubmed/29754952](https://www.ncbi.nlm.nih.gov/pubmed/29754952)

------
RobertRoberts
I have been experimenting with weight loss for the past year. My goal it total
weight "control" _not_ loss. Anyone can lose weight, I want to never ever
worry or think about it again.

Today I am at a low of 181.2lbs. I haven't been this weight for probably over
12 years.

Last summer I did a month of running 6 days a week (increased distance as I
went) + 1 meal a day (strict). And lost .5-.6lbs a day in 30 days. I went from
202 to 187. I gained some of it back by December. I was fluxuating between
192-195.

Then I changed my tactic, did strength exercising for one month, got up to
198, didn't lose weight at all.

Current experiment: I changed two things -

1\. I said "it's ok/fine/good to be hungry". I now naturally eat one meal a
day, I eat when I want, but I don't fool myself. Sometime I eat only a couple
bites of something to ease my stomach.

2\. No exercise during this time at all. No running, lifting, pushups,
nothing.

I have gone from 198 to 181 from last January to Oct, 2018. (17lbs) Not eating
is what makes you lose weight. Being hungry is your body telling you it's
eating fat. I even went to a wedding, gained 3 lbs in 3 days, and shed them
again 3 days later. (obviously not all of it stuck on me in the first place)

After awhile you get used to being hungry, your diet matches your need and
intake. Be hungry, control your weight, it's liberating. I never have to worry
again the rest of my life how to manage my weight.

~~~
newnewpdro
TL;DR: there's no need to feel hungry, you can graze on plain intact
vegetables all day long. Use calisthenic exercise to keep you honest through
feedback.

My experience going from 225lbs to 165lbs and keeping it there for over a
decade now +-5lbs suggests there's no need to feel hungry at all, as long as
I'm eating the right foods.

I didn't use any exercise, just removed sugars and most refined carbohydrates
and processed foods in general. Most the food I eat by volume is raw organic
produce. I can eat plain heads of lettuce all day long and I will not gain
weight. I eat canned wild sardines, salmon, and sometimes tuna for protein and
omega-3s, with the occasional (~weekly) meat binge.

Once my weight stabilized at 165, physical activity became a lot more
appealing so I started hiking, running, doing hand stands, pushups, generally
being more active and this has given me a more masculine physique but doesn't
seem to play much part in maintaining my weight.

Sometimes I experiment by ceasing most physical activity for a week or two,
and mostly what happens is I become less sexy looking, the weight is more or
less the same with the uniform mostly-produce diet. My mood does deteriorate
though.

When I deviate from the diet, usually for social reasons, eating meat more
often or letting more refined carbs and generally processed foods in, my
weight immediately goes up.

Another thing I've learned to appreciate about physical activity is the
feedback it provides. Calisthenics like hand stands, pushups, pullups, all
give direct feedback on your power:weight ratio. It's a lot more impactful to
only be able to do 80 pushups when last week you were doing 100 every day,
than see your weight increased by 10lbs on a bathroom scale. This feedback,
for me, plays a more significant role in maintaining my weight through diet
via exercise than any direct calorie burning.

~~~
RobertRoberts
It seems we arrived at the same place with similar tactics. Not sure where I
will stop thinking about going down, and stay at a particular weight yet.

I find eating produce that just gets rid of hunger to be more unsatisfying
that just being hungry.

I really really enjoy my dinner when I am hungry most of the day. My food is
incredibly appealing and I have no concerns about how much I eat or what it is
(generally speaking). So I guess the comparison here is "be hungry + eating
whatever you want at the end of the day" vs "graze on vegetables all day".

My experiment is coming to a close soon though, as I am with you on the
exercise benefits. My body is starting to get aches that I used to get before
I started exercising. I've run regularly for years, but it didn't shed any
weight unless I was perfectly diligent, which isn't something I could maintain
just for weight loss.

Hence, I found the source to weight loss/control without extra effort, don't
eat much. If I gain weight, eat less until it's gone. Exercise then is purely
for strength and health, (and happiness as you have also found out) but not
weight loss.

Happy to hear you got this under control in your life.

------
fermienrico
The way this article is written is very off-putting.

For instance, "We run around chasing our kids to eat cookies and drink juice,
and then wonder why we have a childhood obesity crisis. Good job, everybody,
good job."

I am not sure if I understand this: "The median daily intake duration (the
amount of time people spent eating) was 14.75 hours per day. That is, if you
started eating breakfast at 8am, you didn’t, on average, stop eating until
10:45pm."

I certainly spend may be 1 hour eating everyday including breakfast, lunch and
dinner.

~~~
kranner
The author means time between first and last food intakes of the day, not
total time spent eating.

~~~
fermienrico
I see. So then this statement is not correct "The median daily intake duration
(the amount of time people spent eating) was 14.75 hours per day.".

It should be "The time between first and last meal during waking hours".

"The amount of time people spend eating" statement is totally wrong.

~~~
baddox
It’s common terminology when referring to fasting, and it’s pretty clear from
context. Apply the principle of charity: it’s highly unlikely that the author
is making the ludicrous claim that people on average are literally eating food
constantly for 14.75 hours a day.

------
reasonattlm
Calorie restriction is probably the most important aspect of short term
fasting of the sort achieved by eating only in some parts of the day.

Animal studies show that isocaloric intermittent fasting, altering eating
schedules, to e.g. alternate day, while still ingesting the same amount of
calories, do have benefits. Those benefits hit many of the same areas of
metabolism as calorie restriction, but are still significantly different in
their overall operation. They are also not as effective at extending life.

Time spent being hungry might be a good metric, but even that is overly
simplistic. Grehlin has all sorts of regulatory connections throughout
metabolism, but you can't point to any one thing. All of these dietary
changes, less calories or more hunger, cause sweeping changes throughout
metabolism that are not well understood as a whole. Cause and effect and which
parts are important versus not is very much open for debate for any part of
this system.

Further, fasting (or fasting mimicking) for longer periods is clearly a
different beast from just rescheduling a few meals. In humans fasting for 72
hours or more results in very different outcomes for immune health than
anything less than 72 hours. The longer fast kills up to a third of the immune
system, which then repopulates when the individual starts eating again, and
thus has very beneficial effects in people whose immune system is damaged or
dysfunctional in some way (e.g. as the results of chemotherapy).

Similarly these longer fasts produce changes to insulin metabolism that last
for months after the fasting is done, which is not the case for fasting in the
rearranging a few meals sense.

~~~
onewhonknocks
I may have misunderstood, but the article stated the following:

‘The two arms of the study were eating between 8am and 8pm, and the eTRF
strategy of eating between 8am and 2pm, but remember, both groups ate three
meals per day of the same foods.’

So it's not like the time restricted people took in less calories. Both groups
consumed the same total amount of calories.

Please correct me if I'm wrong.

~~~
reasonattlm
If that study was isocaloric, then good for them for adding some human data to
the existing animal data.

I'll qualify my remark: most people who practice restricted eating hours in
some way won't count calories or aggressively try to ensure they otherwise eat
the same amount and type of food, and thus the mechanism for benefits will be
largely that of calorie restriction.

------
megaman8
i've been fasting 15-16 hours a day everyday for the last 6 years and it's
certainly helped me keep my weight about 10 lbs lower than I would have with
just dieting. Before that I always subscribed to 3-5 meals a day hypothesis.
Once I switched over to fasting 16 hours, I noticed the effect immediately, by
losing 10 lbs in 2 months and have kept it off ever since.

------
mysterypie
The volume of ever-changing and contradictory advice about dieting is
maddening. The only dieting advice I truly accept these days is the First Law
of Thermodynamics. In context of dieting, you could state this as, _eat less
(calories) or exercise more (joules) or both, and you will lose weight_.
Absolutely guaranteed by a fundamental law of physics. Yes, it's very hard to
follow this rule, but for me at least a simple rule that is guaranteed to work
is much better that complex rules and theories that inevitably turn out to be
nuanced, dependent on particular genetics or environment, or plain wrong.

~~~
ionforce
I think everyone knows that "works" on paper. But people are looking for
solutions that fit their lifestyle, including human imperfections like the
lack of willpower.

~~~
mysterypie
> I think everyone knows that "works" on paper.

You'd think so, but people with science or math degrees have said, _it doesn
't work for me_, even though I point out that we're talking about laws of
physics, not about willpower. Never mind the average person. The average
person will not agree that "eat less, exercise more, _guarantees_ weight
loss".

Regarding your other point, I know that everyone is looking for a shortcut,
trick, or something that works for them. I'm saying that with the insane
volume of unreliable studies and advice, it's simpler to ignore it all and try
one rule that will work.

------
southphillyman
I have been doing IF for a month or two now. Hard to really quantify it's
effects since I've been eating much better and going to the gym during that
same time period. Either way I think it's useful if only as a way to make
eating at a calorie deficit easier. My biggest gripe is that it's basically
impossible to have a social nightlife on the weekends if you can't eat or
drink after 8pm

~~~
ccmonnett
If time-restricted eating is having that big of an impact on your life, adapt
to it. Eat lunch later on the following days after going out, or - and stop me
if this is crazy - don't be so strict about it if your friends want to meet
up.

I am a time-restricted eater. I use Zero to track my eating windows and make
sure I'm not trending in the wrong direction, and that gives me the peace of
mind to let up every once in a while.

Just this morning I broke my fast early because I didn't eat enough last night
and I was pretty zonked before my workout (beyond the point I thought would be
productive). I ate a few dates, recorded it in Zero, and will live to fast
another day.

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gdsdfe
It's fascinating that we're still using the term 'guru' in 2018

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mythrwy
A good cleanout a few times a year is great, but skipping meals and walking
around hungry on a regular basis doesn't work for me at all.

3 reasonable sized meals a day with maybe a light snack is just right. No
heavy meals, not too much carbs (but not no carbs either). Plenty of
vegetables and fruit and protein. Regularly, in small amounts through the day.
Keeps me at the right weight, blood sugar not spiked, not off.

Being hungry I have trouble focusing. And mood gets off. I make worse
decisions.

Not sure why this fad is so promoted lately, maybe it works for some people
but not me and "our ancestors starved" isn't really a good reason to torture
oneself for no discernible reason in my opinion.

------
jcoffland
Many people don't like this but it all boils down to calories in calories out.
All human bodies work pretty much the same way with some slight variances due
to disease and genetics. Fasting works because it restricts your overall
intake.

~~~
Tharkun
Many people don't get this, but calories aren't a very reliable measure of
available energy. Measuring the caloric content of food is a pretty weird
process, and is some kind of "one size fits all" measure of energy which we
might be able to extract. The digestive system is not an engine, where you put
in fuel, add oxygen, combust and use the energy. The digestive system is more
like a mining operation which extracts coal from the bedrock that is your
food, and which then throws it over the wall where billions of consumers burn
the coal for energy.

That process isn't anywhere near 100% efficient. There is a huge amount of
complexity in how food is digested and broken down into protein/sugars/fats.
Some people can't even break down certain foods. Even more complexity in how
those macronutrients are then dealt with.

Sure, in any system energy in == energy out. But without a way of reliably
measuring how much _available_ energy there _really_ is in food for a
_specific body_ , there's really no way you can say "calories in, calories
out".

~~~
jcoffland
It's a simple matter of measuring the calorie content of the food going in
minus that of the waste going out. There are many things that contain calories
that humans don't digest well but the things we tend to eat have pretty
consistent calorie digestion to waste ratios, regardless of the eater. Beliefs
to the contrary are mostly driven by the food fad industry.

------
overcast
A 16 hours fast is so easily achievable that many probably do it without even
knowing. If you stop eating by 8PM, and skip breakfast till lunch at noon.
That's a 16 hour fast. I've done that basically my entire adult life without
even consciously thinking about it. These days I push it out to anywhere from
18-20 hours, and limit my calorie intake from 2pm-8pm. I've been slim my whole
life, 175lbs at 6'1\. Never get sick, last time I've been to the doctors was
easily 20 years ago as a child. Haven't had an antibiotic since grade school.
Cardio exercise daily, hiking mountains, no loss of energy.

------
octygen
Am interesting read. IF is supported by much science and I even studied it in
a Coursera course on brain hacking. Along with Mediterranean diet and Keto,
it's great for the brain and body apparently.

That said, the best advice my Cirque-coach gave me: match food intake with
exercise in a given day. So if do a killer workout today, intermittent fasting
is not going to give me enough fuel. But if I sit around in meetings/writing
6AM-10PM, fasting for 16h and eating in 8h of that day could work as it'll
simply be lessening how much you one eats.

------
matachuan
Never thought I'd see this on here...There is no need for all the
complications like IF, etc. This game is only about your caloric deficient and
surplus.

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freecodyx
as a muslim, i have to fast for a whole month (non stop) each year, it's hard,
but i can clearly see the benefits during and after.

~~~
swebs
What do you mean by non stop? Does that mean you consume 0 calories for the
entire month?

~~~
wishinghand
Just during daylight hours.

------
embwbam
For athletes, how does one reconcile IF with the idea that one should eat
protein at regular intervals? They seem to conflict.

[https://www.climbing.com/skills/climbing-nutrition-how-
much-...](https://www.climbing.com/skills/climbing-nutrition-how-much-protein-
does-a-climber-need/)

~~~
vlasev
I'm not able to look for articles on this right now, but I believe that it was
shown that your overall daily intake of protein is more important than the
time of ingestion.

~~~
embwbam
That’s the exact opposite result as the studies listed in the article I
posted. Weird.

------
tw1010
My main qualm with intermittent fasting is that it makes me hungry, which
depletes my will-power budget for the day (which prevents me from being
productive later in the day). Is there any diet that works better than IF (or
just as well), given the constraint that it also needs to minimize use of your
daily self-dicipline resevoire?

~~~
martin-adams
I find that happens when I also have carbs during my eating window. By
reducing carbs and increasing fat, I’ve noticed less hunger feelings and more
mental clarity.

------
jordache
>It was likely the successful efforts of snack-food companies advertising to
dietitians, and doctors, clueless about nutrition at the best of times, who
simply went along for the ride.

How did he make that determination? Oh I see "likely"

------
mark_l_watson
I am participating right now in one of these studies (Stanford University).

Amazingly, you really don’t get hungry at night after a breaking in period. I
eat between 9am and 6pm, so not quite the same time period as in the article.

------
projektir
This doesn't sound like it was controlled for simply eating less calories.

~~~
oxymoran
Because it wasn’t and that’s not the point. Everybody already knows a caloric
deficit results in weight loss. The point, and the control, was that the same
person, eating the exact same caloric intake exhibited different outcomes
solely based on the time of day the ate.

~~~
projektir
> Everybody already knows a caloric deficit results in weight loss.

I can assure you "everybody" doesn't already know that, in fact, this seems to
be a _minority_ opinion.

The vast majority of people seem to think they need a diet (i.e., restriction
on type of food) to lose weight. The only people I know who are actually on
CICO are people I encouraged to try it.

~~~
gore90-
I can't get over how many people on here are suggesting that knowing about
CICO is "useless". Why? Because it is an oversimplification?

They underestimate how many people literally do not believe that eating at a
caloric deficit would result in weight loss.

------
jgrahamc
Am I meant to know who Jason Fung is? Means nothing to me.

~~~
wishinghand
Just the same as some readers not knowing Alan Kay or Richard Stallman.

------
sys_64738
I fast for 18 hours every day and only eat during a six hour window. I've done
this for 5 months now and lost about 15 pounds.

------
barbecue_sauce
THE Jason Fung?

------
tzs
This needs a title change to the article's actual title:

"A diet guru explains why you should eat dinner at 2pm"

The submitted title:

"Jason Fung explains why intermittent fasting and ADF diets work"

is bad because the article doesn't appear to [1] use the term "ADF" anywhere.
Google tells me that probably stands for "Alternate Day Fasting", which also
doesn't appear to be anywhere in the article.

[1] I'm saying "appear to" because I've been burned before by browser search
functions missing something because the site did something like have some
markup interrupt a word or maybe have some invisible character in the middle
of it.

~~~
ionforce
And who is Jason Fung? Does his name have any cachet?

~~~
fbnlsr
Jason Fung is Canadian nephrologist. He's been working with obese and type 2
diabetes patients for years. He's been advocating fasting and time-restricted
eating for years to fight obesity and diabetes. He's mostly known for this
book "The Obesity Code" in which he details how modern eating habits are wrong
and the main cause for the obesity epidemic.

I hope I summed it up well. You might want to look him up on Youtube, he has
some really interesting talks.

------
atomical
> This was not merely an American phenomenon. More recently, China has
> followed in America’s footsteps with increased snacking. Large-scale surveys
> show that from 1991 to 2009, the percentage of children and adults who
> regularly snack has skyrocketed. Among children aged 13 to 18, those who
> snacked went from 8.7% to 46.3% — a more than fivefold increase. Adults
> showed the a similar rise from 8.7% to 35.6%.

Even so obesity rates are still low in Asian countries. I guess Asians are
enjoying eating throughout the day while still outperforming Americans.

[https://www.oecd.org/els/health-systems/Obesity-
Update-2017....](https://www.oecd.org/els/health-systems/Obesity-
Update-2017.pdf)

------
aviv
Fasting, in particular prolonged fasting (up to 40 days of water fasting or 8
days of dry fasting) is the best gift you can give to your body.

~~~
viach
Saying this in public can cause someone to actually follow your advice without
consulting a doctor and, well, u know, die.

