Episode #189
In this Fasting Q&A episode, hosted by Coach Lisa Chance, Dr. Jason Fung answers questions from the TFM Community:
- I’ve been fasting for six months and was surprised to discover on my annual screening that I am in the early stages of iron deficiency. I am post-menopausal, typically eat red meat twice a week, and fast twice a week. I have been restricting my protein intake but have been taking iron supplements. Should I take iron supplements when I am fasting and are there other things I should consider with fasting as a way of life? [02:03]
- I recently found out I have high histamine, either from diet and/or not being able to process it. I was wondering if longer fasts, say over 24 hours, would help to get rid of high histamine and settle my body down? [05:37]
- I can physically feel when I am losing weight. I feel a mild tingling on the back of my thighs and glutes. It doesn’t really bother me and I look forward to the sensation as I know I am headed in the right direction. Is there a name for this sensation and is it a cellular, biochemical function? I like to think of it as fat cells dissolving! [09:41]
- What are your thoughts on dry fasting? [12:58]
- What is the allowable ketone level while fasting for two to three days (on a strict ketogenic/carnivore diet), and at what level should you break your fast? [15:36]
- If you have a lot of weight to lose and a lot of extra skin, how much dietary protein do you *really* need to eat during your meals? Don’t you want your body to scavenge that extra protein? Does it make a difference to fast with water, salt, and magnesium only, as opposed to using fasting aids such as bone broth? [17:47]
- How does fasting affect blood circulation? [20:16]
- Please can you explain the difference between autophagy and chaperone autophagy? [21:30]
- Can you please explain what is happening when you take vinegar to reduce the impact of blood sugar spikes after eating? [23:02]
- I don’t seem to be able to get beyond 50 hours when doing longer fasts. Is there a reason for this or is it just that 50 hours is my sweet spot when it comes to fasting? [27:43]
LINKS:
Fasting for Kidney Disease - Surprising Benefits
https://youtu.be/Uyjg5S_ef9k?si=6700whbBLEv8ouML
#106 Bitesize: Is ADF Fasting Better?
https://www.thefastingmethod.com/bitesize-is-adf-fasting-better/
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Episode Transcript
Available transcripts are automatically generated. Complete accuracy is not guaranteed.
(00:06):
Before we get started with today's episode,
I would like to quickly read you our podcast
disclaimer.
This podcast is for educational purposes
only, and it is not a substitute
for professional care by a doctor
or other qualified medical professional.
You should always speak with your physician
(00:27):
or other healthcare professionals before doing
any fasting, changing your diet
in any way, taking or adjusting
any medications or supplements, or
adopting any treatment plan
for a health problem.
The use of any other products or
services purchased by you as a result
of this podcast does not create
(00:50):
a healthcare provider-patient relationship
between you and any of the experts
affiliated with this podcast.
Any information and statements
regarding dietary supplements have not
been evaluated by the Food and Drug
Administration and are not intended
to diagnose, treat, cure, or
(01:11):
prevent any disease.
All right. And now we'll get started with
today's episode.
Hello, everyone.
Welcome, welcome. A warm welcome
to our podcast listeners who will be able to
listen to this Q&A with Dr. Fung in a few
weeks and, of course, to all our Community
members that get access to it right away.
(01:32):
This is a monthly Q&A with Dr. Jason
Fung, where he answers questions submitted
by our TFM Community members.
So, good morning, Dr. Fung.
I hope you're having a happy holiday season.
Yes, Thank you so much.
One person did send in a question about
the difference between 36-hour fasts and
48-hour fasts.
I wanted to direct them to podcast #60
(01:55):
and to #106.
Remember, always, the best fast is the
one you can do and consistency is
key.
So I'm going to start off the bat here
with kind of a questionable question that's
between kind of nutrition and medical,
so we'll skirt the edges of medical,
but this person said that she's been
fasting for six months and she learned on
(02:18):
her annual screening that she has
early-stage iron deficiency.
Her doctor ruled out all the other factors:
internal bleeding, stomach acid issues.
She typically eats red meat twice a week
and she is post-menopausal, so there's no
blood loss.
She's wondering how this could have happened.
She fasts two days a week, so that's about a
(02:38):
30% decrease in her meals.
She is also restricting protein more
than before.
She knows that iron comes from mainly from
meat. Of course, it has other-- you know,
dark, leafy greens and things like that also
have iron in them.
But she said she's surprised by this
and she's begun taking an iron supplement.
(02:58):
And I caution people what you take the iron
supplement with. Be sure to take it with
vitamin C, as opposed to something that's
going to block it. I had one client who was
using almond nut butter to take it
and almond blocks the iron
absorption. So her question is, "Should
I supplement with iron while I'm fasting
or am I going to have to do it forever?
(03:20):
What other micronutrients should I be
concerned about with fasting as a way of
life?"
Yeah, so really iron
deficiency is a whole topic, so I can't really
address that specifically because
there's more to it than just fasting.
Fasting - you don't take any nutrients,
obviously, during the fast, so,
certainly, if you're low in iron, then it
(03:41):
could be worse.
Certain foods, as mentioned, are higher
- so the red meats and stuff.
Limiting protein - you can do it,
but you don't have to do it. Like a lot of
these things, you want to try to adjust your
diet to what works for
you. For some people, eating more
protein works, and for some people, eating too
much protein doesn't work.
(04:01):
So it's-- you know, you don't necessarily
have to if there are other reasons that you
shou-- you think you should be taking more.
Really, the total iron losses
in a day are not that much because you
shouldn't be-- you know, iron is found mostly
in blood, and you shouldn't really be losing a
lot of blood on a chronic basis.
There's actually not that much iron in most
(04:22):
meals and stuff, most foods and stuff,
other than meats, and organ meats, and liver
in particular, but a lot of vegetarians
and stuff do get a bit iron deficient because
there's not that much iron sometimes in them.
So should fasting cause iron deficiency?
Probably not. We always check iron, actually,
in our clinics because we don't want to be
blamed for it.
(04:43):
So we pick up a lot of iron deficiency before
they even start, and it can certainly happen
while you're doing it. So it's not really-- I
wouldn't really considered it a cause of it,
but certainly it can happen in conjunction
with it.
But you should be eating nutrient dense
foods anyway when you're eating because you're
not fasting all the time.
So if you're fasting some of the time, then
(05:05):
you should be eating more of those foods
that-- you know, the micronutrients that you
need. So iron isn't one of the ones
that we typically see go
down. Magnesium is probably one of the
ones that we see go down a lot, where people
get cramps. Sodium is another one, so people
take these. You know, you can take some broth
and so on. But iron deficiency, it wouldn't
really be a cause of it, so
(05:27):
you just have treat it separately.
But it's not just because you're fasting, it
shouldn't be the only cause of iron
deficiency. Mostly you have to look for blood
loss.
This next question is interesting because I
know my personal results from it.
So this person asks, "I recently
found out that I struggle with having high
histamine, either from diet and/or
(05:49):
being able to process it.
And I'm wondering if longer fasts (say,
over 24 hours) would help get rid
of the high histamine and settle my body
down."
Yeah, that's a good question because there's
not a lot of data on fasting and histamines,
but a few people have mentioned that to me, as
well, that they had these-- you know, they
were always breaking out in hives, all these
(06:11):
allergic reactions and stuff.
And then once they started fasting, it really
sort of settled it down.
I'm not really sure the mechanism of why
that is, and I haven't seen a lot of data
as to why fasting would help.
But on the other hand, I have heard a couple
of cases. So there may be something to it.
There's just not a lot of research in it.
Fasting can help a lot of things because
(06:33):
a lot of, like, histamines, and autoimmune
diseases, and stuff are where you have, sort
of, this overactivity of the
inflammatory system.
So maybe cutting down certain foods or cutting
down all foods allows that inflammation to
settle down.
Sometimes because insulin is a nutrient
sensor, it actually lowers the activity
of everything in the body, and maybe that's
(06:54):
one of the reasons that it may help.
So I don't know the specifics of it, but
certainly a couple of people have mentioned
the same thing. And if it helps, then it
doesn't even really matter why it helps.
As long as it helps, then I would just go with
that. The fact that it helps
is the most important thing.
Why it helps is secondary, right?
If it helps, it helps.
If it doesn't help, then it doesn't matter why
(07:16):
it should help, right?
So people always get confused because they
say, "Well, you know, this thing helped me,"
and then somebody says, "Well, it shouldn't,"
and then they stop doing it.
But it's like, well, why would you do that?
Perhaps it's the placebo effect, but it
doesn't matter because the placebo effect
is real. If you get better, you get
better. Whether it's due to a placebo
(07:36):
effect or whether it's due to a real effect,
I don't know, and it doesn't matter for the
individual person.
If you think it's helping you, then I would
keep doing it. If you don't think it helps,
then don't. But the research always
lags, you know, sometimes ten years,
15 years. If there's no money in it, you
know, sometimes the research lags for decades.
(07:56):
I found your YouTube video
'Fasting for Kidney Disease (07:59):
Surprising
Benefits' very informative.
I loved how you were talking about autophagy,
and I actually applied that to what happened
with me with histamines, which I would say
I'm less reactive to histamine now, probably
by 90%.
I've really improved my histamine
reaction, which I usually got a migraine from
(08:20):
that. And one of the things you talk about
on that is that decreasing that
inflammation allows the autophagy
to maybe do some healing, and that's what
they're looking at with the kidney.
So why not with the mast-cell reaction?
Yeah, thanks. That was the most recent video
and it was very interesting because,
as a nephrologist, kidney disease
(08:42):
is what I do, and it actually showed all
this benefit. So, interestingly enough,
it had all these benefits for
diabetic kidney disease, but that's expected
because the diabetes gets better.
What was unexpected, to me anyway, which
I talk about in this video, was that the
researchers-- they used the fasting-mimicking
diet, so it's not the same thing.
It's a specific protocol that they used.
(09:04):
Now, whether that applies to all fasting, I
don't know, but they showed that, in fact, for
all these other diseases (IgA nephritis,
membranous nephritis, all these things that
are actually very difficult to treat, and even
just chronic kidney disease by itself), it
improved it, and this autophagy, the
fibrosis-- so a lot of these mechanisms that
we talk about could certainly apply
to mast cells and other things.
(09:25):
So, you know, to me, it's super, super
interesting.
It's fascinating, the whole thing.
People are getting Nobel Prizes studying
autophagy. [laughter] I loved that video
because you went into so much that was
just causing epiphanies in my little brain,
so thank you.
This next question is, "I
can physically feel when I'm losing
(09:46):
weight. It's hard to describe, but
it's on the back of my thighs and my glutes,
and I feel a mild, tingling sensation.
Sometimes it's very mild, sometimes
it's a little more.
It's like when an arm or leg falls
asleep, but much, much milder
than that. It doesn't really bother me.
I rather look forward to the sensation because
(10:08):
I know I'm headed in the right direction.
Is there a name for this sensation
and is it a cellular, biochemical function?
I like to think of it as fat cells
dissolving!" [laughter]
Lisa, you were mentioning that you looked it
up. Maybe you can fill us in a little bit on
what you found.
I found that it's called l i
(10:29):
p o l y s i s - lipo--?
Lipolysis.
Lipolysis, sorry, and neural
activity.
When the fat cells break down with this
lipolysis they release fatty acids,
and this process involves blood flow
and nerve signaling in the fatty tissues.
These changes can trigger mild,
(10:49):
tingling sensation.
Adipose tissue changes.
Fat cells start shrinking and it can affect
local pressure on the nerve endings.
Changes in the tissue fluid happens
during fat loss and this causes a subtle
sensation in areas with more
subcutaneous fat.
It also has a hormonal effect.
(11:10):
During fat breakdown, various hormones
and signaling molecules are released.
These can affect local nerve endings.
Norepinephrine, in particular,
increases during fat breakdown.
While there isn't a specific medical
term for this exact sensation,
during weight loss, it is likely related
(11:31):
to increased local metabolism
in fat tissue, changes in
your circulation, and the neural response
to tissue remodeling,
which is very, very exciting.
Yeah, I actually think it's fascinating, and I
actually think it's true because I notice a
little bit of that as well when I fast.
(11:51):
Again, it's very mild, so I always just put
it down to, oh, well, maybe I'm just paying
more attention to it.
But now that you mention it, I actually also
notice similar things, usually with a little
bit of a longer fast.
Like, not the shorter ones, but with the
longer ones, I definitely think
that I've felt it, but it's so subtle that I
always think, "Oh, I think I'm just-- it's
(12:11):
nice, right, but I think it's in my
mind. So it's actually interesting.
I didn't even know that other people felt it.
And it does feel like that.
You start to feel it and you think, "Oh, it's
my fat cells dissolving." So that's amazing,
right? So I actually just thought it was
just-- you know, I thought it was all just
psychosomatic, sort of.
[laughs]
I had the weird feeling when I was losing a
(12:33):
lot of my weight that I could feel the smaller
person inside.
It's so hard to describe that feeling.
It was like, I can feel this smaller
person emerging out of this fat, so
it's interesting. So it's definitely nerve
tingling that's going on.
And people don't realize that the fat is
innervated with nerves throughout,
so, yeah, it's interesting.
(12:55):
So, this next question is,
"What are your thoughts on dry fasting?"
Dry fasting is interesting.
First of all, dry fasting means that you
don't drink anything, so, not only
are you not eating (which is fasting), you're
also not drinking anything, so no water and
stuff. Because you're not drinking anything,
you can become dehydrated.
So it's actually quite important to make sure
(13:18):
that you are watching yourself and
you're not getting sick and so on.
And it's limited because you
really can't go for more than 24 hours,
and you really shouldn't go for more than like
18 hours without drinking something.
So, again, it's one of these things that's
really interesting because I never thought it
was a great idea, at first, but
(13:38):
then people would say, "Well, it's actually a
lot easier." And then it happened
that I was doing some fasting, and, again,
not long stuff, it was just like I didn't eat
breakfast and I didn't wind up eating lunch,
but a couple of days I didn't drink anything
either. And that wasn't deliberate, it was
just because I got really busy.
So normally I have some coffee, I have some
tea and stuff, but that day I was
(13:58):
very busy and so I didn't drink anything.
I actually thought it was a lot easier.
It was strange.
And I was still urinating, which-- you know, I
just think about these things because,
you know, it interests me, but I still
urinating. So what happens, of course,
is that they say that when you're releasing
glycogen, when you're releasing during the
lipolysis, when your fat cells are releasing
(14:19):
fat, they actually realease some water as
well, which is true because you often
see this really quick drop in your weight,
initially, with fasting, and that's water
weight. So if your body has enough
water, then maybe you don't need to drink,
right? So the dry fasting I always
thought was doable but not something
that you needed to do.
But having done it a few times
(14:42):
(again, mostly inadvertently), I actually did
think it was a lot easier.
So it all depends on the person.
So again, you can't go more than a day.
So if you go 12 hours, 13, 14
hours at the most, then you'd want to start to
drink something.
But, for that period of time, if you wanted
to try the dry fasting, I think it's
reasonable to do because, if
it's easier, then you're
(15:04):
more likely to do it again, right?
And, of course, this is typical of
Ramadan fasting, which is a dry
fast from sunup to sundown, which is sort
of 12 to 14 hours, which is right in that
window where it would be okay not to drink
something. But, once you get more than that,
then, yeah, don't push it because you don't
want to get dehydrated.
It can be dangerous. And if you're on
(15:26):
diuretics and stuff, you want to be careful.
But I found it surprising that it was actually
much easier.
Okay, thank you.
This next question is, "What
is the 'allowable' ketone level while
fasting for two to three days?
If you're on a strict ketogenic or carnivore
diet, is it over 6 or under
(15:46):
7? Is that acceptable or allowable?
When should you break your fast?"
There's no good data on that because,
you know, ketones are supposed to rise
when you fast or when you're following an
ketogenic diet.
But then some people, because they're
measuring it, they find it really high and
then they always get worried about it.
The thing is that I don't know what level is
(16:07):
too high.
You know, there's ketoacidosis, which is
different - you see that with diabetes
where you have too little insulin.
It used to be called starvation ketosis.
So when you don't eat, when you starve or when
you fast, the ketones are supposed to go up.
But what level is too high?
That's actually not a question that's
knowable. A lot of people get worried because
(16:27):
of the association of diabetic ketoacidosis.
They say, "Well, maybe it's also
bad for you to have too many ketones." But the
point of the ketoacidosis is not the ketones
so much, it's the lack of insulin that causes
the acid part of it.
So when they talk about starvation ketosis,
it's not ketoacidosis, right?
It's a different entity completely.
(16:49):
So I don't actually have any data.
If you're not diabetic, if you're not on
one of these medications that can cause
ketoacidosis, then I'm not
sure that there is any upper limit of
ketones that is actually dangerous.
We usually say 6.9 - right there.
But if they're on like an
(17:10):
SGLT2, we sometimes say 4.0.
So it's very individualized.
Yeah, the SGLT2s cause ketoacidosis,
so, certainly, that would be a worry that
you're developing the ketoacidosis.
The question is the ketosis - how
bad is it? It's a good question.
You know, the data is not there.
I mean, if it's too high-- some people,
(17:31):
they go very high and then they break their
fast but then they can't lose any way because
their ketones always go high, in which case
then you have to start saying, "Well, maybe
you have to just monitor it and see,"
see what-- you know, how you feel and make
sure that you're always doing that.
This next question is, "If you have a lot
of weight to lose and a lot of extra skin,
(17:51):
how much dietary protein do you *really*
need to eat during your meals?
Don't you want your body to scavenge
that extra protein?
Does it make a difference to fast with water,
salt, and magnesium only, as opposed
to using a fasting aid such as bone broth?"
Yeah, I would think so.
The skin is an interesting question
(18:12):
because, again, there's not a lot of studies
on it. [laughs] We have just noticed it
ourselves, when we are treating a lot of
people. Skin is protein
and so is connective tissue.
Connective tissue is all the stuff that
holds the cells together.
It's like the scaffolding for your
cells, your body, and so on.
So, you know, in the past people would say,
(18:33):
"Well, burning protein, like you see with
gluconeogenesis that you get in fasting--
at around 24 to 30 hours or
so you get this gluconeogenesis.
People used to say, "Oh, that's really bad.
You're losing lean tissue," and so on.
But lean tissue is not the same as muscle.
In fact, people who are overweight, not
only have extra fat, but they need all these
(18:53):
sort of supporting structures for that fat,
which is the skin, which is the connective
tissue, and the blood vessels.
So that's why you see on those TV shows, you
know, where they lose a lot of weight and
stuff, they actually wind up going to surgery
to cut out like 20 pounds of skin
sort of thing. The skin is protein.
So you actually want your body-- your body can
(19:14):
break that down.
So, yes, I would think that--
to me, I would try to do the sort
of water and electrolytes only,
rather than the bone broth, because you're
really trying to get the body to break down
its own protein.
And then I would try to keep it in that
sort of 24 to 36-hour range,
because, remember, when you get past that,
(19:36):
you're burning fat (which is good) but
you're not burning protein.
So if you can get it into that stage
where you're getting a bit of that
gluconeogenesis, which we know happens
somewhere between 20 and 30 hours,
and then just keep going to there, going to
there, right? Once you're getting past that 30
hours, you're mostly breaking down fat.
So it's good too, you can do it occasionally,
(19:57):
but, if skin is your major issue,
try and keep into that 20 to 30-hour
range as much as you can, so doing it maybe
three, four times a week rather than
just doing a three-day, full fast, right,
because then at least you get that 20 to 30
hours three times as opposed to just once.
Thank you, Dr. Fung.
"How does fasting affect blood
(20:18):
circulation, generally?"
Fasting doesn't directly impact
it. I mean, it reduces
the blood sugars and so on.
So, over time, if you have less diabetes,
less obesity, you may have less
atherosclerosis, which is the major impediment
for blood flow.
So blood flow is-- when we
(20:39):
think about blood flow, the main problem we
have is that it doesn't get enough blood,
right? And that's caused by the
atherosclerosis, which is that plaque
in the artery that's blocking.
That causes heart attacks, and strokes, and
gangrene, and all this sort of stuff.
So the major risk for that, or one of the
major risks, is high blood pressure-- and
diabetes are two major, major risks.
(21:01):
Modifiable risks.
I mean, there's age, and sex, and genetics,
and stuff, but you can't do anything about
those. So, because
the fasting and the diet play a role in
hypertension and diabetes, then, over time,
it can certainly make it better.
They do these studies, too, sometimes where
they measure blood flow to the forearm and
stuff and, you know, you see short-term
(21:22):
changes, but it's mostly the long-term changes
that we're interested in.
Fascinating.
Somebody sent this in, and I have never heard
this term before.
It says, "Please explain the difference
between autophagy and chaperone
autophagy.
When autophagy happens, the damaged essential
amino acids are rebuilt as well.
Is that correct?"
(21:43):
Yeah.
Autophagy is sort of three things:
microautophagy, macroautophagy, and chaperone
autophagy [chaperone-mediated autophagy].
It's a little bit more complex.
And again, autophagy, itself is a
relatively new field,
so I'm not sure how much applies only
to chaperone autophagy versus
macroautophagy.
(22:03):
Mostly, what we talk about is macroautophagy,
actually, so I don't know too much about it.
I haven't seen too much about chaperone
autophagy, specifically.
The other thing they talk about with autophagy
is mitophagy, which is basically autophagy
as applies to mitochondria.
And the fasting is actually quite beneficial
in the mitophagy, which is making sure
(22:24):
that the mitochondria break down so that
you can sort of rebuild them, right, so
encouraging metabolic flexibility,
where you can use either glucose or fat as a
fuel. So all of those are related
because those are really important in terms,
not so much of diabetes, weight gain sort of
thing, but more for longevity and,
(22:44):
you know, overall health.
But it can play a role.
So I don't know that much about chaperone
autophagy, specifically, but for sure.
Me neither.
[laughter] I looked it up and I was like,
"Okay!" [laughs] Like I said,
Nobel Prize people are working on this stuff,
so--.
This person asks the question, "Can you please
explain what is happening when you take
(23:05):
vinegar to reduce the impact of
a blood- sugar spike after eating?
I know we want to avoid glucose spikes.
Doesn't that just shove more glucose into
the fat cells rather than keeping it
in the circulation where I presume
it would be burned more easily?"
Yeah, so vinegar is very interesting because,
remember, carbohydrates are chains
(23:27):
of glucose.
So if you look at bread, for example,
it's composed of starches, which is
composed of two structures called amylopectin
or amylose, and they're long chains of
glucose. If you take that, your body
can't absorb that.
It would just pass right through you if you
ate it, because your body can only absorb
glucose as a single molecule.
(23:48):
When you string hundreds, millions of these
molecules together, it's a big long chain.
So that's how they used to classify a complex
carbohydrate - had more than two, right?
A simple carbohydrate was
like sugar, which was glucose and fructose, so
two molecules versus a starch,
which was considered a complex carbohydrate
because it had like two million glucose
(24:08):
molecules all linked together.
They don't use that anymore because it doesn't
really matter. What matters is how quickly
you absorb that glucose.
So the question is how do you absorb that
glucose? Well, you break it down
and you use enzymes called amylase.
So amylase is something that breaks these
chains. So if you have all these chains, you
have two million glucose molecules, you
(24:30):
use amylase to break them up, and then you
break them into single or double molecules.
Now your body can absorb that glucose.
If you can break it down very quickly,
then you absorb it quickly and you get this
huge glucose spike.
The problem with the huge glucose spike is
that insulin also spikes along with it, and
insulin drives a lot of weight gain.
If you add vinegar or
(24:51):
lemon juice or fermented foods, which
are acidic foods, what happens is
that you inhibit salivary amylase.
So the amylase in your saliva
is working at breaking down the starch
as soon as you eat it.
And when it goes down into the stomach, it's
still working on it, right?
If you inhibit it (that is, you take
(25:11):
the acidic food like the vinegar), then
your amylase gets blocked, so
it's not working nearly as well.
So these long chains are not getting broken
down and, therefore, not getting absorbed.
So the rise in your glucose is much,
much slower.
If it eventually passes through, then you
don't absorb it because it's gone through,
(25:32):
you haven't broken it down, and the intestines
can't absorb these huge, you know,
million-long chains of glucose, right?
They don't absorb like single or double
glucose. So that's the reason that
you get less of this glucose spike.
Then you can measure the so-called 'area
under the curve', which is that if you eat a
food and it spikes really high
(25:53):
but it comes down really quick, versus how
much area is under the curve, you get the sort
of total glucose and total insulin
effect over time.
So not how high it spikes up,
but how much effect it has *total*
over that period of time.
And what you see is that the vinegar is
actually going to reduce that by a significant
amount - 30, 40, 50%.
(26:14):
So that is if you take bread versus
if you take bread with vinegar,
the total effect, the total glucose
that your body is seeing is going to
be about 30, 40, 50% less
than that. So that's good.
You're not getting as much glucose.
Basically, it's not getting into your body
nearly the same. You're not being exposed to
(26:35):
the same amount of insulin that
you normally would.
You know, it's not the carbohydrate,
necessarily, it's the insulin that's driving
all this effect. So if there's a way that you
can sort of reduce it--
You see the same thing with processed
carbs versus natural carbs.
So you can take oatmeal.
If you compare steel-cut oats (where they
have the whole oat and they just cut it)
(26:56):
versus instant oats (which is ground
up really fine), it's the same calories,
the same carbohydrates, in fact, the very same
food, but, just the way that
you prepare it (steel-cut versus instant),
again, there's a huge difference.
One has a very, very high glycemic index,
one has a medium glycemic index.
The total exposure of your body
(27:19):
to the glucose is about 50%
less. This is the very same food.
It's not the carbohydrates, necessarily, it's
not even the calories.
It's the way that your body breaks it down
does make a real difference.
And that's where the vinegar and stuff can be
very useful. If you are taking carbohydrates,
then, yeah, it's an easy sort of thing to
add or put into your diet
(27:41):
there.
Okay, so this person has been struggling
with longer fasts.
She goes 50 hours.
She's been doing this for about a year,
all right? She does carnivore or
ketovore, switches back and forth.
And she's tried to do the longer
fasts, like a three-day fast or a five-day
fast. Her max is 50 [hours]
(28:02):
and then she starts having the signs
and symptoms that people usually get when they
first begin fasting and they're first trying
to get to like a 24.
And she's taking her salt, she's taking
magnesium, she's even taking a little bit of
potassium.
And she's finding that they're not helpful
at that point in time, whereas they're helpful
at the beginning of the fast.
And so she's just wondering, is it just
(28:24):
that she needs to continue to build her
fasting muscle or is
there some other explanation?
Has she just hit her sweet spot at 50?
It could certainly be that.
What I would say, though, is that it's not
necessary to do a
five-day fast with just water-only
because more and more of these
(28:45):
studies that are coming out are using
this sort of fasting, but not
a full fast.
So I'll tell you, one of the companies,
L-Nutra, which does the fasting-mimicking
diet, which has done a lot of studies.
To their credit, they've actually put a lot of
money into research at these major
universities and stuff.
It's a five-day fast every month, but it's not
a full fast, they actually take some food with
(29:07):
it. So it's very low-glycemic-index,
sort of low-protein sort of thing.
They're trying not to stimulate insulin,
but have you take some food.
So basically you could do the same with
vegetables.
There's also a lot of data on the 5:2
diet, which is another fasting regimen -
five days of eating normally, two days of
fasting - but, again, that's not a full fast.
(29:28):
It's 500 calories per day for that
fast. So more and more of these studies
are coming out using these sort of regimens,
and they're just seeing crazy benefits,
like, as-good benefits.
So, you know, I don't think it's necessary
to-- if you're going to do five days,
and you're getting problems at day three, day
four, maybe just take a bit of vegetables
(29:50):
or something like that, a little bit of soup,
that will help you.
And I've done that, actually, because the last
two five-day fasts that I did,
because of some of the studies, I thought,
"Well, let me try this instead," which is
fast-- instead of full fast, I'll just do it
with food.
And there's two major benefits.
One, is that it actually makes it easier
because, from a social standpoint, it's a
(30:11):
little awkward sometimes when you're doing a
long fast and you're going out for-- you're
having dinner with your family or something
and you're just sitting there.
On the other hand, if I'm just sitting there,
but I'm eating a little bit of vegetables,
it's not a lot of calories, it's not a lot of
carbohydrates, it's usually, like, you know,
a bit of steamed broccoli and some soup,
right, but at least I'm there.
So socially it's a lot easier.
(30:31):
So it makes it a lot easier to do.
Physiologically, I find myself not thinking
about food as much because I did eat a little
bit, and the benefits were almost the
same. Everything seemed about the same
to me. It didn't make a huge difference.
So, again, if it makes it easier and
you're getting like 80, 90% of the benefits,
then, hey, why not?
(30:52):
So because the data is starting to show
that, hey, it doesn't have to be a full fast,
I think that it's probably-- and you're
having trouble, then do that - take a little
bit of vegetables. So what I do, and
I don't know if this is the right thing-- I
mean, you could always get the
fasting-mimicking [diet] where they do it
every day, but I usually fast for two to three
(31:13):
days, and then, by day three, day four, I
take a little bit of vegetables, right?
And that seemed pretty good
to me. And it's a good compromise between
being like a strict purist and saying,
"Well, I'm getting most of the benefits,
like it's 50% easier, but
I'm getting 80% of the benefits." That's a net
plus, right?
It makes it a lot easier overall.
(31:34):
So that's something to consider.
And everybody can do their own thing.
But, if you are having trouble, then I would
say, yeah, absolutely, try that - a little bit
of vegetables, green vegetables, you
know, on day three and day four -
and see if that is enough to just push you
through so that you get the continued
benefits. Remember, the little bit of
calories-- even though you're getting the
calories, you're not stimulating the insulin a
(31:56):
lot. It's about lowering the insulin, lowering
the mTOR, so that's not a lot of protein
there. There's not a lot of calories there,
there's not a lot of carbohydrates there, but
it's something right?
There's something in your stomach.
I get a lot less of this rumbling in my
stomach, which is sometimes annoying at times.
So, yeah, try that and see
how it goes because it can really be useful.
Thank you, Dr. Fung, and I highly recommend
(32:19):
everyone watch his latest video,
which is 'Fasting for Kidney Disease:
Surprising Benefits'.
He talks a lot about the different autophagy
in there, so I highly recommend it.
Thank you so much, Dr. Fung, and I look
forward to seeing you next month in the New
Year. Woohoo!
Yeah, absolutely. And I do have a YouTube
live, as well, that I do
(32:39):
once a month. So if you join my YouTube
community, you can go on there.
It's a little different. I don't answer the
questions so much.
I try to answer a few questions, but not
nearly as many as I do here.
It's about a half an hour as well.
Mostly, I just go over sort of what's
happening, and what's new, and all that sort
of thing, but, if you want, you can go on the
YouTube live.
I forgot to mention people are loving the new
cohort that we started, the 12-week thing.
(33:01):
So I know you and Megan put a lot of work into
that, and people are really, really
taking to it like ducks to water.
Good, good. I was hoping-- yeah, we
were trying to get something a lot more
prescriptive and guiding people more
through it, like pointing out specific things
that they should be doing and trying to do it
all together because, remember, that's what
we're here for, is we're trying to help each
(33:23):
other. So if everybody is doing the same
thing, it'll be a lot easier.
We can talk about the same things, we can
watch the same things, and it'll give us a bit
of, you know, that emotional support
that most of us need to get through it.
So yeah, I'm hoping that that's going to be
very helpful for people.
So I'm glad to hear that.
Thank you so much, Dr. Fung.
Bye.
Before we get started with today's episode,
I would like to quickly read you our podcast
disclaimer.
This podcast is for educational purposes
only, and it is not a substitute
for professional care by a doctor
or other qualified medical professional.
You should always speak with your physician
(00:27):
or other healthcare professionals before doing
any fasting, changing your diet
in any way, taking or adjusting
any medications or supplements, or
adopting any treatment plan
for a health problem.
The use of any other products or
services purchased by you as a result
of this podcast does not create
(00:50):
a healthcare provider-patient relationship
between you and any of the experts
affiliated with this podcast.
Any information and statements
regarding dietary supplements have not
been evaluated by the Food and Drug
Administration and are not intended
to diagnose, treat, cure, or
(01:11):
prevent any disease.
All right. And now we'll get started with
today's episode.
Hello, everyone.
Welcome, welcome. A warm welcome
to our podcast listeners who will be able to
listen to this Q&A with Dr. Fung in a few
weeks and, of course, to all our Community
members that get access to it right away.
(01:32):
This is a monthly Q&A with Dr. Jason
Fung, where he answers questions submitted
by our TFM Community members.
So, good morning, Dr. Fung.
I hope you're having a happy holiday season.
Yes, Thank you so much.
One person did send in a question about
the difference between 36-hour fasts and
48-hour fasts.
I wanted to direct them to podcast #60
(01:55):
and to #106.
Remember, always, the best fast is the
one you can do and consistency is
key.
So I'm going to start off the bat here
with kind of a questionable question that's
between kind of nutrition and medical,
so we'll skirt the edges of medical,
but this person said that she's been
fasting for six months and she learned on
(02:18):
her annual screening that she has
early-stage iron deficiency.
Her doctor ruled out all the other factors:
internal bleeding, stomach acid issues.
She typically eats red meat twice a week
and she is post-menopausal, so there's no
blood loss.
She's wondering how this could have happened.
She fasts two days a week, so that's about a
(02:38):
30% decrease in her meals.
She is also restricting protein more
than before.
She knows that iron comes from mainly from
meat. Of course, it has other-- you know,
dark, leafy greens and things like that also
have iron in them.
But she said she's surprised by this
and she's begun taking an iron supplement.
(02:58):
And I caution people what you take the iron
supplement with. Be sure to take it with
vitamin C, as opposed to something that's
going to block it. I had one client who was
using almond nut butter to take it
and almond blocks the iron
absorption. So her question is, "Should
I supplement with iron while I'm fasting
or am I going to have to do it forever?
(03:20):
What other micronutrients should I be
concerned about with fasting as a way of
life?"
Yeah, so really iron
deficiency is a whole topic, so I can't really
address that specifically because
there's more to it than just fasting.
Fasting - you don't take any nutrients,
obviously, during the fast, so,
certainly, if you're low in iron, then it
(03:41):
could be worse.
Certain foods, as mentioned, are higher
- so the red meats and stuff.
Limiting protein - you can do it,
but you don't have to do it. Like a lot of
these things, you want to try to adjust your
diet to what works for
you. For some people, eating more
protein works, and for some people, eating too
much protein doesn't work.
(04:01):
So it's-- you know, you don't necessarily
have to if there are other reasons that you
shou-- you think you should be taking more.
Really, the total iron losses
in a day are not that much because you
shouldn't be-- you know, iron is found mostly
in blood, and you shouldn't really be losing a
lot of blood on a chronic basis.
There's actually not that much iron in most
(04:22):
meals and stuff, most foods and stuff,
other than meats, and organ meats, and liver
in particular, but a lot of vegetarians
and stuff do get a bit iron deficient because
there's not that much iron sometimes in them.
So should fasting cause iron deficiency?
Probably not. We always check iron, actually,
in our clinics because we don't want to be
blamed for it.
(04:43):
So we pick up a lot of iron deficiency before
they even start, and it can certainly happen
while you're doing it. So it's not really-- I
wouldn't really considered it a cause of it,
but certainly it can happen in conjunction
with it.
But you should be eating nutrient dense
foods anyway when you're eating because you're
not fasting all the time.
So if you're fasting some of the time, then
(05:05):
you should be eating more of those foods
that-- you know, the micronutrients that you
need. So iron isn't one of the ones
that we typically see go
down. Magnesium is probably one of the
ones that we see go down a lot, where people
get cramps. Sodium is another one, so people
take these. You know, you can take some broth
and so on. But iron deficiency, it wouldn't
really be a cause of it, so
(05:27):
you just have treat it separately.
But it's not just because you're fasting, it
shouldn't be the only cause of iron
deficiency. Mostly you have to look for blood
loss.
This next question is interesting because I
know my personal results from it.
So this person asks, "I recently
found out that I struggle with having high
histamine, either from diet and/or
(05:49):
being able to process it.
And I'm wondering if longer fasts (say,
over 24 hours) would help get rid
of the high histamine and settle my body
down."
Yeah, that's a good question because there's
not a lot of data on fasting and histamines,
but a few people have mentioned that to me, as
well, that they had these-- you know, they
were always breaking out in hives, all these
(06:11):
allergic reactions and stuff.
And then once they started fasting, it really
sort of settled it down.
I'm not really sure the mechanism of why
that is, and I haven't seen a lot of data
as to why fasting would help.
But on the other hand, I have heard a couple
of cases. So there may be something to it.
There's just not a lot of research in it.
Fasting can help a lot of things because
(06:33):
a lot of, like, histamines, and autoimmune
diseases, and stuff are where you have, sort
of, this overactivity of the
inflammatory system.
So maybe cutting down certain foods or cutting
down all foods allows that inflammation to
settle down.
Sometimes because insulin is a nutrient
sensor, it actually lowers the activity
of everything in the body, and maybe that's
(06:54):
one of the reasons that it may help.
So I don't know the specifics of it, but
certainly a couple of people have mentioned
the same thing. And if it helps, then it
doesn't even really matter why it helps.
As long as it helps, then I would just go with
that. The fact that it helps
is the most important thing.
Why it helps is secondary, right?
If it helps, it helps.
If it doesn't help, then it doesn't matter why
(07:16):
it should help, right?
So people always get confused because they
say, "Well, you know, this thing helped me,"
and then somebody says, "Well, it shouldn't,"
and then they stop doing it.
But it's like, well, why would you do that?
Perhaps it's the placebo effect, but it
doesn't matter because the placebo effect
is real. If you get better, you get
better. Whether it's due to a placebo
(07:36):
effect or whether it's due to a real effect,
I don't know, and it doesn't matter for the
individual person.
If you think it's helping you, then I would
keep doing it. If you don't think it helps,
then don't. But the research always
lags, you know, sometimes ten years,
15 years. If there's no money in it, you
know, sometimes the research lags for decades.
(07:56):
I found your YouTube video
'Fasting for Kidney Disease (07:59):
Surprising
Benefits' very informative.
I loved how you were talking about autophagy,
and I actually applied that to what happened
with me with histamines, which I would say
I'm less reactive to histamine now, probably
by 90%.
I've really improved my histamine
reaction, which I usually got a migraine from
(08:20):
that. And one of the things you talk about
on that is that decreasing that
inflammation allows the autophagy
to maybe do some healing, and that's what
they're looking at with the kidney.
So why not with the mast-cell reaction?
Yeah, thanks. That was the most recent video
and it was very interesting because,
as a nephrologist, kidney disease
(08:42):
is what I do, and it actually showed all
this benefit. So, interestingly enough,
it had all these benefits for
diabetic kidney disease, but that's expected
because the diabetes gets better.
What was unexpected, to me anyway, which
I talk about in this video, was that the
researchers-- they used the fasting-mimicking
diet, so it's not the same thing.
It's a specific protocol that they used.
(09:04):
Now, whether that applies to all fasting, I
don't know, but they showed that, in fact, for
all these other diseases (IgA nephritis,
membranous nephritis, all these things that
are actually very difficult to treat, and even
just chronic kidney disease by itself), it
improved it, and this autophagy, the
fibrosis-- so a lot of these mechanisms that
we talk about could certainly apply
to mast cells and other things.
(09:25):
So, you know, to me, it's super, super
interesting.
It's fascinating, the whole thing.
People are getting Nobel Prizes studying
autophagy. [laughter] I loved that video
because you went into so much that was
just causing epiphanies in my little brain,
so thank you.
This next question is, "I
can physically feel when I'm losing
(09:46):
weight. It's hard to describe, but
it's on the back of my thighs and my glutes,
and I feel a mild, tingling sensation.
Sometimes it's very mild, sometimes
it's a little more.
It's like when an arm or leg falls
asleep, but much, much milder
than that. It doesn't really bother me.
I rather look forward to the sensation because
(10:08):
I know I'm headed in the right direction.
Is there a name for this sensation
and is it a cellular, biochemical function?
I like to think of it as fat cells
dissolving!" [laughter]
Lisa, you were mentioning that you looked it
up. Maybe you can fill us in a little bit on
what you found.
I found that it's called l i
(10:29):
p o l y s i s - lipo--?
Lipolysis.
Lipolysis, sorry, and neural
activity.
When the fat cells break down with this
lipolysis they release fatty acids,
and this process involves blood flow
and nerve signaling in the fatty tissues.
These changes can trigger mild,
(10:49):
tingling sensation.
Adipose tissue changes.
Fat cells start shrinking and it can affect
local pressure on the nerve endings.
Changes in the tissue fluid happens
during fat loss and this causes a subtle
sensation in areas with more
subcutaneous fat.
It also has a hormonal effect.
(11:10):
During fat breakdown, various hormones
and signaling molecules are released.
These can affect local nerve endings.
Norepinephrine, in particular,
increases during fat breakdown.
While there isn't a specific medical
term for this exact sensation,
during weight loss, it is likely related
(11:31):
to increased local metabolism
in fat tissue, changes in
your circulation, and the neural response
to tissue remodeling,
which is very, very exciting.
Yeah, I actually think it's fascinating, and I
actually think it's true because I notice a
little bit of that as well when I fast.
(11:51):
Again, it's very mild, so I always just put
it down to, oh, well, maybe I'm just paying
more attention to it.
But now that you mention it, I actually also
notice similar things, usually with a little
bit of a longer fast.
Like, not the shorter ones, but with the
longer ones, I definitely think
that I've felt it, but it's so subtle that I
always think, "Oh, I think I'm just-- it's
(12:11):
nice, right, but I think it's in my
mind. So it's actually interesting.
I didn't even know that other people felt it.
And it does feel like that.
You start to feel it and you think, "Oh, it's
my fat cells dissolving." So that's amazing,
right? So I actually just thought it was
just-- you know, I thought it was all just
psychosomatic, sort of.
[laughs]
I had the weird feeling when I was losing a
(12:33):
lot of my weight that I could feel the smaller
person inside.
It's so hard to describe that feeling.
It was like, I can feel this smaller
person emerging out of this fat, so
it's interesting. So it's definitely nerve
tingling that's going on.
And people don't realize that the fat is
innervated with nerves throughout,
so, yeah, it's interesting.
(12:55):
So, this next question is,
"What are your thoughts on dry fasting?"
Dry fasting is interesting.
First of all, dry fasting means that you
don't drink anything, so, not only
are you not eating (which is fasting), you're
also not drinking anything, so no water and
stuff. Because you're not drinking anything,
you can become dehydrated.
So it's actually quite important to make sure
(13:18):
that you are watching yourself and
you're not getting sick and so on.
And it's limited because you
really can't go for more than 24 hours,
and you really shouldn't go for more than like
18 hours without drinking something.
So, again, it's one of these things that's
really interesting because I never thought it
was a great idea, at first, but
(13:38):
then people would say, "Well, it's actually a
lot easier." And then it happened
that I was doing some fasting, and, again,
not long stuff, it was just like I didn't eat
breakfast and I didn't wind up eating lunch,
but a couple of days I didn't drink anything
either. And that wasn't deliberate, it was
just because I got really busy.
So normally I have some coffee, I have some
tea and stuff, but that day I was
(13:58):
very busy and so I didn't drink anything.
I actually thought it was a lot easier.
It was strange.
And I was still urinating, which-- you know, I
just think about these things because,
you know, it interests me, but I still
urinating. So what happens, of course,
is that they say that when you're releasing
glycogen, when you're releasing during the
lipolysis, when your fat cells are releasing
(14:19):
fat, they actually realease some water as
well, which is true because you often
see this really quick drop in your weight,
initially, with fasting, and that's water
weight. So if your body has enough
water, then maybe you don't need to drink,
right? So the dry fasting I always
thought was doable but not something
that you needed to do.
But having done it a few times
(14:42):
(again, mostly inadvertently), I actually did
think it was a lot easier.
So it all depends on the person.
So again, you can't go more than a day.
So if you go 12 hours, 13, 14
hours at the most, then you'd want to start to
drink something.
But, for that period of time, if you wanted
to try the dry fasting, I think it's
reasonable to do because, if
it's easier, then you're
(15:04):
more likely to do it again, right?
And, of course, this is typical of
Ramadan fasting, which is a dry
fast from sunup to sundown, which is sort
of 12 to 14 hours, which is right in that
window where it would be okay not to drink
something. But, once you get more than that,
then, yeah, don't push it because you don't
want to get dehydrated.
It can be dangerous. And if you're on
(15:26):
diuretics and stuff, you want to be careful.
But I found it surprising that it was actually
much easier.
Okay, thank you.
This next question is, "What
is the 'allowable' ketone level while
fasting for two to three days?
If you're on a strict ketogenic or carnivore
diet, is it over 6 or under
(15:46):
7? Is that acceptable or allowable?
When should you break your fast?"
There's no good data on that because,
you know, ketones are supposed to rise
when you fast or when you're following an
ketogenic diet.
But then some people, because they're
measuring it, they find it really high and
then they always get worried about it.
The thing is that I don't know what level is
(16:07):
too high.
You know, there's ketoacidosis, which is
different - you see that with diabetes
where you have too little insulin.
It used to be called starvation ketosis.
So when you don't eat, when you starve or when
you fast, the ketones are supposed to go up.
But what level is too high?
That's actually not a question that's
knowable. A lot of people get worried because
(16:27):
of the association of diabetic ketoacidosis.
They say, "Well, maybe it's also
bad for you to have too many ketones." But the
point of the ketoacidosis is not the ketones
so much, it's the lack of insulin that causes
the acid part of it.
So when they talk about starvation ketosis,
it's not ketoacidosis, right?
It's a different entity completely.
(16:49):
So I don't actually have any data.
If you're not diabetic, if you're not on
one of these medications that can cause
ketoacidosis, then I'm not
sure that there is any upper limit of
ketones that is actually dangerous.
We usually say 6.9 - right there.
But if they're on like an
(17:10):
SGLT2, we sometimes say 4.0.
So it's very individualized.
Yeah, the SGLT2s cause ketoacidosis,
so, certainly, that would be a worry that
you're developing the ketoacidosis.
The question is the ketosis - how
bad is it? It's a good question.
You know, the data is not there.
I mean, if it's too high-- some people,
(17:31):
they go very high and then they break their
fast but then they can't lose any way because
their ketones always go high, in which case
then you have to start saying, "Well, maybe
you have to just monitor it and see,"
see what-- you know, how you feel and make
sure that you're always doing that.
This next question is, "If you have a lot
of weight to lose and a lot of extra skin,
(17:51):
how much dietary protein do you *really*
need to eat during your meals?
Don't you want your body to scavenge
that extra protein?
Does it make a difference to fast with water,
salt, and magnesium only, as opposed
to using a fasting aid such as bone broth?"
Yeah, I would think so.
The skin is an interesting question
(18:12):
because, again, there's not a lot of studies
on it. [laughs] We have just noticed it
ourselves, when we are treating a lot of
people. Skin is protein
and so is connective tissue.
Connective tissue is all the stuff that
holds the cells together.
It's like the scaffolding for your
cells, your body, and so on.
So, you know, in the past people would say,
(18:33):
"Well, burning protein, like you see with
gluconeogenesis that you get in fasting--
at around 24 to 30 hours or
so you get this gluconeogenesis.
People used to say, "Oh, that's really bad.
You're losing lean tissue," and so on.
But lean tissue is not the same as muscle.
In fact, people who are overweight, not
only have extra fat, but they need all these
(18:53):
sort of supporting structures for that fat,
which is the skin, which is the connective
tissue, and the blood vessels.
So that's why you see on those TV shows, you
know, where they lose a lot of weight and
stuff, they actually wind up going to surgery
to cut out like 20 pounds of skin
sort of thing. The skin is protein.
So you actually want your body-- your body can
(19:14):
break that down.
So, yes, I would think that--
to me, I would try to do the sort
of water and electrolytes only,
rather than the bone broth, because you're
really trying to get the body to break down
its own protein.
And then I would try to keep it in that
sort of 24 to 36-hour range,
because, remember, when you get past that,
(19:36):
you're burning fat (which is good) but
you're not burning protein.
So if you can get it into that stage
where you're getting a bit of that
gluconeogenesis, which we know happens
somewhere between 20 and 30 hours,
and then just keep going to there, going to
there, right? Once you're getting past that 30
hours, you're mostly breaking down fat.
So it's good too, you can do it occasionally,
(19:57):
but, if skin is your major issue,
try and keep into that 20 to 30-hour
range as much as you can, so doing it maybe
three, four times a week rather than
just doing a three-day, full fast, right,
because then at least you get that 20 to 30
hours three times as opposed to just once.
Thank you, Dr. Fung.
"How does fasting affect blood
(20:18):
circulation, generally?"
Fasting doesn't directly impact
it. I mean, it reduces
the blood sugars and so on.
So, over time, if you have less diabetes,
less obesity, you may have less
atherosclerosis, which is the major impediment
for blood flow.
So blood flow is-- when we
(20:39):
think about blood flow, the main problem we
have is that it doesn't get enough blood,
right? And that's caused by the
atherosclerosis, which is that plaque
in the artery that's blocking.
That causes heart attacks, and strokes, and
gangrene, and all this sort of stuff.
So the major risk for that, or one of the
major risks, is high blood pressure-- and
diabetes are two major, major risks.
(21:01):
Modifiable risks.
I mean, there's age, and sex, and genetics,
and stuff, but you can't do anything about
those. So, because
the fasting and the diet play a role in
hypertension and diabetes, then, over time,
it can certainly make it better.
They do these studies, too, sometimes where
they measure blood flow to the forearm and
stuff and, you know, you see short-term
(21:22):
changes, but it's mostly the long-term changes
that we're interested in.
Fascinating.
Somebody sent this in, and I have never heard
this term before.
It says, "Please explain the difference
between autophagy and chaperone
autophagy.
When autophagy happens, the damaged essential
amino acids are rebuilt as well.
Is that correct?"
(21:43):
Yeah.
Autophagy is sort of three things:
microautophagy, macroautophagy, and chaperone
autophagy [chaperone-mediated autophagy].
It's a little bit more complex.
And again, autophagy, itself is a
relatively new field,
so I'm not sure how much applies only
to chaperone autophagy versus
macroautophagy.
(22:03):
Mostly, what we talk about is macroautophagy,
actually, so I don't know too much about it.
I haven't seen too much about chaperone
autophagy, specifically.
The other thing they talk about with autophagy
is mitophagy, which is basically autophagy
as applies to mitochondria.
And the fasting is actually quite beneficial
in the mitophagy, which is making sure
(22:24):
that the mitochondria break down so that
you can sort of rebuild them, right, so
encouraging metabolic flexibility,
where you can use either glucose or fat as a
fuel. So all of those are related
because those are really important in terms,
not so much of diabetes, weight gain sort of
thing, but more for longevity and,
(22:44):
you know, overall health.
But it can play a role.
So I don't know that much about chaperone
autophagy, specifically, but for sure.
Me neither.
[laughter] I looked it up and I was like,
"Okay!" [laughs] Like I said,
Nobel Prize people are working on this stuff,
so--.
This person asks the question, "Can you please
explain what is happening when you take
(23:05):
vinegar to reduce the impact of
a blood- sugar spike after eating?
I know we want to avoid glucose spikes.
Doesn't that just shove more glucose into
the fat cells rather than keeping it
in the circulation where I presume
it would be burned more easily?"
Yeah, so vinegar is very interesting because,
remember, carbohydrates are chains
(23:27):
of glucose.
So if you look at bread, for example,
it's composed of starches, which is
composed of two structures called amylopectin
or amylose, and they're long chains of
glucose. If you take that, your body
can't absorb that.
It would just pass right through you if you
ate it, because your body can only absorb
glucose as a single molecule.
(23:48):
When you string hundreds, millions of these
molecules together, it's a big long chain.
So that's how they used to classify a complex
carbohydrate - had more than two, right?
A simple carbohydrate was
like sugar, which was glucose and fructose, so
two molecules versus a starch,
which was considered a complex carbohydrate
because it had like two million glucose
(24:08):
molecules all linked together.
They don't use that anymore because it doesn't
really matter. What matters is how quickly
you absorb that glucose.
So the question is how do you absorb that
glucose? Well, you break it down
and you use enzymes called amylase.
So amylase is something that breaks these
chains. So if you have all these chains, you
have two million glucose molecules, you
(24:30):
use amylase to break them up, and then you
break them into single or double molecules.
Now your body can absorb that glucose.
If you can break it down very quickly,
then you absorb it quickly and you get this
huge glucose spike.
The problem with the huge glucose spike is
that insulin also spikes along with it, and
insulin drives a lot of weight gain.
If you add vinegar or
(24:51):
lemon juice or fermented foods, which
are acidic foods, what happens is
that you inhibit salivary amylase.
So the amylase in your saliva
is working at breaking down the starch
as soon as you eat it.
And when it goes down into the stomach, it's
still working on it, right?
If you inhibit it (that is, you take
(25:11):
the acidic food like the vinegar), then
your amylase gets blocked, so
it's not working nearly as well.
So these long chains are not getting broken
down and, therefore, not getting absorbed.
So the rise in your glucose is much,
much slower.
If it eventually passes through, then you
don't absorb it because it's gone through,
(25:32):
you haven't broken it down, and the intestines
can't absorb these huge, you know,
million-long chains of glucose, right?
They don't absorb like single or double
glucose. So that's the reason that
you get less of this glucose spike.
Then you can measure the so-called 'area
under the curve', which is that if you eat a
food and it spikes really high
(25:53):
but it comes down really quick, versus how
much area is under the curve, you get the sort
of total glucose and total insulin
effect over time.
So not how high it spikes up,
but how much effect it has *total*
over that period of time.
And what you see is that the vinegar is
actually going to reduce that by a significant
amount - 30, 40, 50%.
(26:14):
So that is if you take bread versus
if you take bread with vinegar,
the total effect, the total glucose
that your body is seeing is going to
be about 30, 40, 50% less
than that. So that's good.
You're not getting as much glucose.
Basically, it's not getting into your body
nearly the same. You're not being exposed to
(26:35):
the same amount of insulin that
you normally would.
You know, it's not the carbohydrate,
necessarily, it's the insulin that's driving
all this effect. So if there's a way that you
can sort of reduce it--
You see the same thing with processed
carbs versus natural carbs.
So you can take oatmeal.
If you compare steel-cut oats (where they
have the whole oat and they just cut it)
(26:56):
versus instant oats (which is ground
up really fine), it's the same calories,
the same carbohydrates, in fact, the very same
food, but, just the way that
you prepare it (steel-cut versus instant),
again, there's a huge difference.
One has a very, very high glycemic index,
one has a medium glycemic index.
The total exposure of your body
(27:19):
to the glucose is about 50%
less. This is the very same food.
It's not the carbohydrates, necessarily, it's
not even the calories.
It's the way that your body breaks it down
does make a real difference.
And that's where the vinegar and stuff can be
very useful. If you are taking carbohydrates,
then, yeah, it's an easy sort of thing to
add or put into your diet
(27:41):
there.
Okay, so this person has been struggling
with longer fasts.
She goes 50 hours.
She's been doing this for about a year,
all right? She does carnivore or
ketovore, switches back and forth.
And she's tried to do the longer
fasts, like a three-day fast or a five-day
fast. Her max is 50 [hours]
(28:02):
and then she starts having the signs
and symptoms that people usually get when they
first begin fasting and they're first trying
to get to like a 24.
And she's taking her salt, she's taking
magnesium, she's even taking a little bit of
potassium.
And she's finding that they're not helpful
at that point in time, whereas they're helpful
at the beginning of the fast.
And so she's just wondering, is it just
(28:24):
that she needs to continue to build her
fasting muscle or is
there some other explanation?
Has she just hit her sweet spot at 50?
It could certainly be that.
What I would say, though, is that it's not
necessary to do a
five-day fast with just water-only
because more and more of these
(28:45):
studies that are coming out are using
this sort of fasting, but not
a full fast.
So I'll tell you, one of the companies,
L-Nutra, which does the fasting-mimicking
diet, which has done a lot of studies.
To their credit, they've actually put a lot of
money into research at these major
universities and stuff.
It's a five-day fast every month, but it's not
a full fast, they actually take some food with
(29:07):
it. So it's very low-glycemic-index,
sort of low-protein sort of thing.
They're trying not to stimulate insulin,
but have you take some food.
So basically you could do the same with
vegetables.
There's also a lot of data on the 5:2
diet, which is another fasting regimen -
five days of eating normally, two days of
fasting - but, again, that's not a full fast.
(29:28):
It's 500 calories per day for that
fast. So more and more of these studies
are coming out using these sort of regimens,
and they're just seeing crazy benefits,
like, as-good benefits.
So, you know, I don't think it's necessary
to-- if you're going to do five days,
and you're getting problems at day three, day
four, maybe just take a bit of vegetables
(29:50):
or something like that, a little bit of soup,
that will help you.
And I've done that, actually, because the last
two five-day fasts that I did,
because of some of the studies, I thought,
"Well, let me try this instead," which is
fast-- instead of full fast, I'll just do it
with food.
And there's two major benefits.
One, is that it actually makes it easier
because, from a social standpoint, it's a
(30:11):
little awkward sometimes when you're doing a
long fast and you're going out for-- you're
having dinner with your family or something
and you're just sitting there.
On the other hand, if I'm just sitting there,
but I'm eating a little bit of vegetables,
it's not a lot of calories, it's not a lot of
carbohydrates, it's usually, like, you know,
a bit of steamed broccoli and some soup,
right, but at least I'm there.
So socially it's a lot easier.
(30:31):
So it makes it a lot easier to do.
Physiologically, I find myself not thinking
about food as much because I did eat a little
bit, and the benefits were almost the
same. Everything seemed about the same
to me. It didn't make a huge difference.
So, again, if it makes it easier and
you're getting like 80, 90% of the benefits,
then, hey, why not?
(30:52):
So because the data is starting to show
that, hey, it doesn't have to be a full fast,
I think that it's probably-- and you're
having trouble, then do that - take a little
bit of vegetables. So what I do, and
I don't know if this is the right thing-- I
mean, you could always get the
fasting-mimicking [diet] where they do it
every day, but I usually fast for two to three
(31:13):
days, and then, by day three, day four, I
take a little bit of vegetables, right?
And that seemed pretty good
to me. And it's a good compromise between
being like a strict purist and saying,
"Well, I'm getting most of the benefits,
like it's 50% easier, but
I'm getting 80% of the benefits." That's a net
plus, right?
It makes it a lot easier overall.
(31:34):
So that's something to consider.
And everybody can do their own thing.
But, if you are having trouble, then I would
say, yeah, absolutely, try that - a little bit
of vegetables, green vegetables, you
know, on day three and day four -
and see if that is enough to just push you
through so that you get the continued
benefits. Remember, the little bit of
calories-- even though you're getting the
calories, you're not stimulating the insulin a
(31:56):
lot. It's about lowering the insulin, lowering
the mTOR, so that's not a lot of protein
there. There's not a lot of calories there,
there's not a lot of carbohydrates there, but
it's something right?
There's something in your stomach.
I get a lot less of this rumbling in my
stomach, which is sometimes annoying at times.
So, yeah, try that and see
how it goes because it can really be useful.
Thank you, Dr. Fung, and I highly recommend
(32:19):
everyone watch his latest video,
which is 'Fasting for Kidney Disease:
Surprising Benefits'.
He talks a lot about the different autophagy
in there, so I highly recommend it.
Thank you so much, Dr. Fung, and I look
forward to seeing you next month in the New
Year. Woohoo!
Yeah, absolutely. And I do have a YouTube
live, as well, that I do
(32:39):
once a month. So if you join my YouTube
community, you can go on there.
It's a little different. I don't answer the
questions so much.
I try to answer a few questions, but not
nearly as many as I do here.
It's about a half an hour as well.
Mostly, I just go over sort of what's
happening, and what's new, and all that sort
of thing, but, if you want, you can go on the
YouTube live.
I forgot to mention people are loving the new
cohort that we started, the 12-week thing.
(33:01):
So I know you and Megan put a lot of work into
that, and people are really, really
taking to it like ducks to water.
Good, good. I was hoping-- yeah, we
were trying to get something a lot more
prescriptive and guiding people more
through it, like pointing out specific things
that they should be doing and trying to do it
all together because, remember, that's what
we're here for, is we're trying to help each
(33:23):
other. So if everybody is doing the same
thing, it'll be a lot easier.
We can talk about the same things, we can
watch the same things, and it'll give us a bit
of, you know, that emotional support
that most of us need to get through it.
So yeah, I'm hoping that that's going to be
very helpful for people.
So I'm glad to hear that.
Thank you so much, Dr. Fung.
Bye.
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