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  • "Breakfast of champions."

  • What's the difference between eating less food and eating no food?

  • Well, Let's look at two different situations.

  • In 1944, a study called the Minnesota Starvation Experiment was conducted and was designed

  • to understand the effects of caloric restriction on the body in order to gain some knowledge

  • that would help people starving in the aftermath of World War 2.

  • Thirty-six healthy men with an average height of 178cm (about five foot ten) and average

  • weight of 69.3 kilograms (or 153 pounds) were selected.

  • For three months, they ate a diet of 3200 calories per day.

  • Then, for six months they ate only 1570 calories.

  • However, caloric intake was adjusted to attempt to have the men lose 1.1 kilograms per week,

  • meaning some men got less than 1000 calories per day.

  • The foods given were high in carbohydrates- things like potatoes, turnips, bread and macaroni.

  • Meat and dairy products were rarely given.

  • During the six months, the men experienced profound physical and psychological changes.

  • Everyone complained that they were too cold.

  • One subject talked about having to wear a sweater in July on a sunny day.

  • The subjects' body temperature dropped to an average of 95.8 degrees Fahrenheit (35.4

  • degrees celsius).

  • Physical endurance dropped by half, and strength showed a 21 percent decrease.

  • The men experienced a complete lack of interest in everything except for food, which they

  • were obsessed with.

  • They were plagued with constant and intense hunger.

  • There were several cases of neurotic behavior like hoarding cookbooks and utensils.

  • Two participants had to be cut from the experiment because they admitted to stealing and eating

  • several raw turnips and taking scraps of food from garbage cans.

  • At first, the participants were allowed to chew gum, until some of the men began chewing

  • up to 40 packages a day.

  • Now compare all this to the case of Angus Barbieri, a Scottish man who in 1965 fasted

  • for over 380 days straight.

  • That is he took in no food whatsoever -nothing but water, black coffee and straight tea for

  • just over a year.

  • He lost 276 pounds, going from from 456 pounds to 180.

  • A case report published by the Dundee University Department of Medicine in 1973 said “...the

  • patient remained symptom-free, felt well and walked about normally,” andProlonged

  • fasting in this patient had no ill-effects.”

  • There were no complaints of mind numbing hunger and he kept the weight off- for several years

  • his weight stayed around 196 pounds.

  • This of course is not a perfect comparison, with the case of Angus, there's only one

  • subject and his starting weight was drastically higher compared to those in the Minnesota

  • Experiment.

  • However, it does illustrate some very interesting points about just how different of a physiological

  • response you get from fasting (that is, eating nothing) compared to eating less, or caloric

  • restriction.

  • Dr. Jason Fung, a Toronto physician specializing in kidney disease, and author of the Obesity

  • Code, says that compared to fasting, Caloric Reduction will result in: less weight loss,

  • more lean mass loss (i.e. more muscle loss), and more hunger.

  • Let's start by talking about hunger.

  • In Upton Sinclair's 1911 bookThe Fasting Cure,” he writes about fasting as a means

  • to improve health.

  • In describing his first couple attempts at fasting he writes “I was very hungry for

  • the first day-the unwholesome, ravening sort of hunger that all dyspeptics know.

  • I had a little hunger the second morning, and thereafter, to my great astonishment,

  • no hunger whatever-no more interest in food than if I had ever known the taste of it.”

  • Sinclair recommends to do quite long fasts - around 12 days or so.

  • In a section addressing concerns about fasting he writesSeveral people have asked me

  • if it would not be better for them to eat very lightly instead of fasting, or to content

  • themselves with fasts of two or three days at frequent intervals.

  • My reply to that is that I find it very much harder to do that, because all the trouble

  • in the fast occurs during the first two or three days.

  • It is during those days that you are hungry.”

  • Then he says: “...perhaps, it might be a good thing to eat very lightly of fruit, instead

  • of taking an absolute fast-the only trouble is that I cannot do it.

  • Again and again I have tried, but always with the same result: the light meals are just

  • enough to keep me ravenously hungry...”

  • In the book he says you will know when you should finish fasting, because your hunger

  • willreturn.”

  • He quotes a letter he received from a 72 year old man sayingAfter fasting twenty-eight

  • days I began to be hungry, and broke my fast with a little grape juice, followed the next

  • day with tomatoes, and later with vegetable soup.

  • He quotes several other letters he received from readers and this disappearance and reappearance

  • of hunger is a common theme.

  • Everyone who wrote to him fasted for at least 10 days, saying they only broke their fast

  • when hungerreturned.”

  • This phenomenon runs contrary to the idea one would get hungrier and hungrier as long

  • as they don't eat.

  • However, most people have experienced for themselves that this is not the case.

  • Some will find that they are not hungry at all in the morning or at least they are not

  • as hungry as they are for lunch or dinner.

  • But unless you are eating in your sleep, the morning is when you have gone the longest

  • without food.

  • Some of this can be explained by the hormone Ghrelin.

  • Ghrelin, known as thehunger hormonehas been found to increase appetite and weight

  • gain.

  • A study at the Medical University of Vienna looked at patients participating in a 33 hour fast.

  • Their ghrelin levels were checked every 20 minutes.

  • Here's how the levels changed over time.

  • What's interesting is ghrelin is lowest at 9:00AM, which is when they have gone the

  • longest without eating.

  • And, Ghrelin comes in waves and overall doesn't rise during the period the subjects were fasting.

  • Then, As you can see, ghrelin rises in sync with normal lunch and dinner times, as if

  • the body had learned to expect food at that time.

  • However, that ghrelin rise spontaneously decreases after 2 hours without food.

  • I've experienced this kind of spontaneous decrease in hunger myself many times when

  • I was working as a consultant.

  • Lunch time would come and I would be hungry, but I was too busy to eat so I just kept working.

  • Pretty quickly I forgot about eating and wasn't particularly hungry until dinner time.

  • This is very helpful to keep in mind if you're doing a long fast or even if you're starting

  • intermittent fasting - you're going to get annoying waves of hunger, especially around

  • the times that you usually eat.

  • But, it won't get worse, the hunger will simply go away if you are patient.

  • Another study concerning ghrelin was done at Aarhus University Hospital in Denmark and

  • it shows what happens if you do a longer fast.

  • They looked at the ghrelin levels of 33 subjects who fasted for 84 hours.

  • So, did they get increasingly hungrier throughout the fasting period?

  • Well, No.

  • Their ghrelin followed similar rhythms each day but actually decreased the longer they

  • fasted.

  • Going longer without food actually made them less hungry.

  • This gives credence to what Upton Sinclair and his readers said about hunger disappearing

  • after the first 3 days of fasting.

  • I've done a couple 5 and 6 day fasts in the past myself and this was indeed the case.

  • Actually, I did a 4 day fast last week and again the 4th day was when I had the least

  • hunger.

  • Another thing that may be contributing to this phenomenon is that you are entering ketosis.

  • Ketosis is a physiological state where your metabolism switches to using primarily fat

  • for energy.

  • For this reason ketosis is popular as a weight loss method, but it has many other benefits

  • including better physical and mental efficiency.

  • Ketosis occurs when you restrict carbohydrates down to 50 grams or less and you don't eat

  • too much protein.

  • Everyone's body is a bit different so you might have to eat even less carbohydrate or

  • may have room for more, but the recommended ratio of a ketogenic diet is to get 5% of

  • your calories from carbs, 25% from protein and 75% from good fat.

  • A simpler way to enter ketosis is just don't eat anything for a long enough time.

  • This is one of the major points in the difference between fasting and caloric restriction.

  • The problem with the subjects in the Minnesota Starvation experiment was that they were eating

  • just enough to keep them out ketosis and keep their metabolism primed for burning carbohydrate

  • (glucose), so they couldn't use their body fat for energy.

  • This explains a lot of things like why they were losing their strength and were very sluggish

  • and cold.

  • It also clears up why Upton Sinclair said fruit or light meals were just enough to keep

  • him ravenously hungry and far weaker than if he had just eaten nothing.

  • As I explained in my last video, insulin is necessary for glucose to get into the cell

  • to be used for energy.

  • When you eat carbohydrates, the pancreas secretes insulin to deal with it and too much insulin

  • hampers the action of something called hormone sensitive lipase which is necessary to mobilize

  • fat and use it for fuel.

  • Though, keep in mind that grains or refined carbohydrates will provoke a much higher insulin

  • response than say green vegetables.

  • Now because the body is having a hard time using its fat for fuel, it will do a couple

  • things: One, it will simply slow down metabolism to preserve energy.

  • In the Minnesota Starvation experiment, the subjects metabolism dropped by 40 percent.

  • Their bodies didn't have access to its stored energy, and their restricted calorie diets

  • don't provide much fuel so there's no choice but to slow down the metabolism.

  • Ironically, in the case of fasting, as Jason Fung points out - metabolism actually goes

  • up.

  • "If you don't do anything about your insulin and just reduce your calories, your metabolism

  • goes down.

  • But what happens during fasting?

  • Well, here's a study of 4 consecutive days of fasting.

  • What happens to your REE - this is this middle line here, that's the resting energy expenditure.

  • It doesn't go down, it goes up.

  • You're burning more energy than you did."

  • The other thing the body will do when it can't use fat for fuel is break down muscle into

  • glucose through a process called gluconeogenesis.

  • The body doesn't want do this too much because it's not very smart to completely eat through

  • something as important as muscle, but when it can't access its own stored energy it's

  • more likely to resort to this.

  • This is why you'll experience more muscle loss on caloric restriction than if you ate

  • nothing.

  • When you are fasting, Human Growth Hormone is released.

  • As the name implies, Human Growth Hormone is an anabolic hormone - a hormone conducive

  • to growth.

  • In Leningher's Principles of Biochemistry textbook they give the example of how injecting

  • the human growth hormone gene into a mouse makes it unusually large.

  • As explained in Guyton's Textbook of Medical Physiology: "...growth hormone also mobilizes

  • large quantities of free fatty acids from the adipose tissue, and these in turn are

  • used to supply most of the energy for the body cells, thus acting as a potent "protein

  • sparer."

  • "That is human growth hormone is protecting your muscles from breaking down.

  • The study I referred to earlier about subjects undergoing an 84 hour fast shows that growth

  • hormone rises significantly after the second day of fasting.

  • As mentioned earlier, you should enter ketosis sometime within the first 3 days or so of

  • fasting, and it depends on how much you are moving around and what your diet was like

  • before starting the fast.

  • The state of ketosis is a great indicator that your body is making good use of its stored

  • body fat for energy.

  • In Tim Ferriss' bookTools of Titans,” Tim talks about his first clinically supervised

  • 7 day fast.

  • For some sort of liability reasons, he wasn't allowed to exercise or leave the facility.

  • Considering exercise is a potent stimulator of human growth hormone and will help deplete

  • glucose stores, not getting any exercise is a great way to prevent yourself from getting

  • into ketosis during a fast.

  • It's also a great way to lose muscle.

  • Tim says he lost 12 pounds of muscle during the overly restrictive clinically supervised

  • 7 day fast.

  • But, when following a protocol designed to get him into ketosis as soon as possible - involving

  • things like 4 hours of brisk walking, he did a ten day fast and apparently lost zero muscle

  • mass.

  • One last factor in Ketosis preserving muscle is leucine.

  • When you're in ketosis, you have a higher fasting blood leucine level.

  • And leucine is a key branch chain amino acid that has an anabolic effect on the body so

  • it preserves lean body mass.

  • A lot of people interested in building muscle may be worried that fasting or a ketogenic

  • diet wouldn't work for them because insulin and therefore carbohydrates are necessary

  • for protein synthesis (i.e. muscle growth), but actually this leucine fills that role

  • and is a good trigger for protein synthesis.

  • So, just to sum all this up: compared to a conventional calorie restricted diet, fasting

  • means you lose more weight in the form of fat, you keep more muscle, you have more energy,

  • and you are less hungry . If proper weight loss is your goal, it might be better to eat

  • nothing at all rather than eating a conventional low calorie diet.

"Breakfast of champions."

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断食 vs 食べる量を減らす (Fasting vs Eating Less)

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    Ming に公開 2021 年 01 月 14 日
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