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The Evolutionary Argument Against Reality

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Amanda Gefter has an interesting interview with Donald Hoffman in Quanta:

As we go about our daily lives, we tend to assume that our perceptions — sights, sounds, textures, tastes — are an accurate portrayal of the real world. Sure, when we stop and think about it — or when we find ourselves fooled by a perceptual illusion — we realize with a jolt that what we perceive is never the world directly, but rather our brain’s best guess at what that world is like, a kind of internal simulation of an external reality. Still, we bank on the fact that our simulation is a reasonably decent one. If it wasn’t, wouldn’t evolution have weeded us out by now? The true reality might be forever beyond our reach, but surely our senses give us at least an inkling of what it’s really like.

Not so, says Donald D. Hoffman, a professor of cognitive science at the University of California, Irvine. Hoffman has spent the past three decades studying perception, artificial intelligence, evolutionary game theory and the brain, and his conclusion is a dramatic one: The world presented to us by our perceptions is nothing like reality. What’s more, he says, we have evolution itself to thank for this magnificent illusion, as it maximizes evolutionary fitness by driving truth to extinction.

Getting at questions about the nature of reality, and disentangling the observer from the observed, is an endeavor that straddles the boundaries of neuroscience and fundamental physics. On one side you’ll find researchers scratching their chins raw trying to understand how a three-pound lump of gray matter obeying nothing more than the ordinary laws of physics can give rise to first-person conscious experience. This is the aptly named “hard problem.”

On the other side are quantum physicists, marveling at the strange fact that quantum systems don’t seem to be definite objects localized in space until we come along to observe them — whether we are conscious humans or inanimate measuring devices. Experiment after experiment has shown — defying common sense — that if we assume that the particles that make up ordinary objects have an objective, observer-independent existence, we get the wrong answers. The central lesson of quantum physics is clear: There are no public objects sitting out there in some preexisting space. As the physicist John Wheeler put it, “Useful as it is under ordinary circumstances to say that the world exists ‘out there’ independent of us, that view can no longer be upheld.”

So while neuroscientists struggle to understand how there can be such a thing as a first-person reality, quantum physicists have to grapple with the mystery of how there can be anything but a first-person reality. In short, all roads lead back to the observer. And that’s where you can find Hoffman — straddling the boundaries, attempting a mathematical model of the observer, trying to get at the reality behind the illusion. Quanta Magazine caught up with him to find out more. An edited and condensed version of the conversation follows.

QUANTA MAGAZINE: People often use Darwinian evolution as an argument that our perceptions accurately reflect reality. They say, “Obviously we must be latching onto reality in some way because otherwise we would have been wiped out a long time ago. If I think I’m seeing a palm tree but it’s really a tiger, I’m in trouble.”

DONALD HOFFMAN: Right. The classic argument is that those of our ancestors who saw more accurately had a competitive advantage over those who saw less accurately and thus were more likely to pass on their genes that coded for those more accurate perceptions, so after thousands of generations we can be quite confident that we’re the offspring of those who saw accurately, and so we see accurately. That sounds very plausible. But I think it is utterly false. It misunderstands the fundamental fact about evolution, which is that it’s about fitness functions — mathematical functions that describe how well a given strategy achieves the goals of survival and reproduction. The mathematical physicist Chetan Prakash proved a theorem that I devised that says: According to evolution by natural selection, an organism that sees reality as it is will never be more fit than an organism of equal complexity that sees none of reality but is just tuned to fitness. Never.

You’ve done computer simulations to show this. Can you give an example?

Suppose in reality there’s a resource, like water, and you can quantify how much of it there is in an objective order — very little water, medium amount of water, a lot of water. Now suppose your fitness function is linear, so a little water gives you a little fitness, medium water gives you medium fitness, and lots of water gives you lots of fitness — in that case, the organism that sees the truth about the water in the world can win, but only because the fitness function happens to align with the true structure in reality. Generically, in the real world, that will never be the case. Something much more natural is a bell curve  — say, too little water you die of thirst, but too much water you drown, and only somewhere in between is good for survival. Now the fitness function doesn’t match the structure in the real world. And that’s enough to send truth to extinction. For example, an organism tuned to fitness might see small and large quantities of some resource as, say, red, to indicate low fitness, whereas they might see intermediate quantities as green, to indicate high fitness. Its perceptions will be tuned to fitness, but not to truth. It won’t see any distinction between small and large — it only sees red — even though such a distinction exists in reality.

But how can seeing a false reality be beneficial to an organism’s survival?

There’s a metaphor that’s only been available to us in the past 30 or 40 years, and that’s the desktop interface. Suppose there’s a blue rectangular icon on the lower right corner of your computer’s desktop — does that mean that the file itself is blue and rectangular and lives in the lower right corner of your computer? Of course not. But those are the only things that can be asserted about anything on the desktop — it has color, position and shape. Those are the only categories available to you, and yet none of them are true about the file itself or anything in the computer. They couldn’t possibly be true. That’s an interesting thing. You could not form a true description of the innards of the computer if your entire view of reality was confined to the desktop. And yet the desktop is useful. That blue rectangular icon guides my behavior, and it hides a complex reality that I don’t need to know. That’s the key idea. Evolution has shaped us with perceptions that allow us to survive. They guide adaptive behaviors. But part of that involves hiding from us the stuff we don’t need to know. And that’s pretty much all of reality, whatever reality might be. If you had to spend all that time figuring it out, the tiger would eat you.

So everything we see is one big illusion?

We’ve been shaped to have perceptions that keep us alive, so we have to take them seriously. If I see something that I think of as a snake, I don’t pick it up. If I see a train, I don’t step in front of it. I’ve evolved these symbols to keep me alive, so I have to take them seriously. But it’s a logical flaw to think that if we have to take it seriously, we also have to take it literally.

If snakes aren’t snakes and trains aren’t trains, what are they?

Snakes and trains, like the particles of physics, have no objective, observer-independent features. The snake I see is a description created by my sensory system to inform me of the fitness consequences of my actions. Evolution shapes acceptable solutions, not optimal ones. A snake is an acceptable solution to the problem of telling me how to act in a situation. My snakes and trains are my mental representations; your snakes and trains are your mental representations.

How did you first become interested in these ideas?

As a teenager, I was very interested in the question “Are we machines?” My reading of the science suggested that we are. But my dad was a minister, and at church they were saying we’re not. So I decided I needed to figure it out for myself. It’s sort of an important personal question — if I’m a machine, I would like to find that out! And if I’m not, I’d like to know, what is that special magic beyond the machine? So eventually in the 1980s I went to the artificial intelligence lab at MIT and worked on machine perception. The field of vision research was enjoying a newfound success in developing mathematical models for specific visual abilities. I noticed that they seemed to share a common mathematical structure, so I thought it might be possible to write down a formal structure for observation that encompassed all of them, perhaps all possible modes of observation. I was inspired in part by Alan Turing. When he invented the Turing machine, he was trying to come up with a notion of computation, and instead of putting bells and whistles on it, he said, Let’s get the simplest, most pared down mathematical description that could possibly work. And that simple formalism is the foundation for the science of computation. So I wondered, could I provide a similarly simple formal foundation for the science of observation?

A mathematical model of consciousness.

That’s right. My intuition was, there are conscious experiences. I have pains, tastes, smells, all my sensory experiences, moods, emotions and so forth. So I’m just going to say: One part of this consciousness structure is a set of all possible experiences. When I’m having an experience, based on that experience I may want to change what I’m doing. So I need to have a collection of possible actions I can take and a decision strategy that, given my experiences, allows me to change how I’m acting. That’s the basic idea of the whole thing. I have a space X of experiences, a space G of actions, and an algorithm D that lets me choose a new action given my experiences. Then I posited a W for a world, which is also a probability space. Somehow the world affects my perceptions, so there’s a perception map P from the world to my experiences, and when I act, I change the world, so there’s a map A from the space of actions to the world. That’s the entire structure. Six elements. The claim is: This is the structure of consciousness. I put that out there so people have something to shoot at.

But if there’s a W, are you saying there is an external world?

Here’s the striking thing about that. I can pull the W out of the model and stick a conscious agent in its place and get a circuit of conscious agents. In fact, you can have whole networks of arbitrary complexity. And that’s the world.

The world is just other conscious agents?

I call it conscious realism: Objective reality is just conscious agents, just points of view. Interestingly, I can take two conscious agents and have them interact, and the mathematical structure of that interaction also satisfies the definition of a conscious agent. This mathematics is telling me something. I can take two minds, and they can generate a new, unified single mind. Here’s a concrete example. We have two hemispheres in our brain. But when you do a split-brain operation, a complete transection of the corpus callosum, you get clear evidence of two separate consciousnesses. Before that slicing happened, it seemed there was a single unified consciousness. So it’s not implausible that there is a single conscious agent. And yet it’s also the case that there are two conscious agents there, and you can see that when they’re split. I didn’t expect that, the mathematics forced me to recognize this. It suggests that I can take separate observers, put them together and create new observers, and keep doing this ad infinitum. It’s conscious agents all the way down.

If it’s conscious agents all the way down, all first-person points of view, what happens to science? Science has always been a third-person description of the world. . .

Continue reading.

Written by LeisureGuy

1 May 2016 at 12:45 pm

Posted in Evolution, Science

Southerners Weren’t ‘Lazy,’ Just Infected With Hookworms

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Hookworm

Sarah Emerson reports in Motherboard:

Stereotypes are almost always the conclusions of lazy science—they’re just empirical generalizations that are stripped of their variances and encoded as fact into the collective consciousness of a general population. They’re the tools of propagandists, xenophobes, and oppressors, and tend to stick around through the ages like a bad smell.

However, sometime a stereotype will reveal a hidden truth that provides an origin to the myth.

The trope of the “lazy Southerner” dates back to America’s postbellum period following the end of the Civil War. No one really knew where it came from, but the image of a lethargic, filthy, drawling farmer has pervaded art, literature, and popular culture up until this very moment.

One argument, recently published by Rachel Nuwer for PBS Nova Next, presents some compelling evidence for the theory that a hookworm epidemic was responsible for this rural stereotype.

The hookworm (Necator americanus) is a parasite that’s been called “the germ of laziness,” due to the exhaustion and mental fogginess it tends to inflict upon its victims. Historical evidence shows the parasite ravaged the American South throughout the early 20th century, as a result of poor sanitation and a lack of public health programs among the poor.

By 1905, the parasitologist Charles Stiles estimated that 40 percent or more of the Southern population was infected with hookworms. The parasite thrives in fecal matter, and the combination of shoddy waste disposal and the rarity of shoes allowed hookworm larvae to enter people’s bodies through the webbing between their toes.

Once hookworms have penetrated the skin, they’ll travel through their host’s lungs and into their intestines, where they’ll survive on a diet of blood they suck out from the intestinal wall. A female hookworm can lay up to 10,000 eggs in a single day, which gives you an idea of how rampant a localized infestation can become in a very short time.

The “laziness” that’s synonymous with hookworm infections is a symptom of iron deficiency anemia, due to blood loss. . .

Continue reading.

 

Written by LeisureGuy

30 April 2016 at 11:34 am

Posted in Daily life, Science

One minute a day of strenuous exercise has same health and fitness benefit as 45 minutes of moderate exercise

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Very interesting article in the NY Times by Gretchen Reynolds. The core:

. . . One group was asked to change nothing about their current, virtually nonexistent exercise routines; they would be the controls.

A second group began a typical endurance-workout routine, consisting of riding at a moderate pace on a stationary bicycle at the lab for 45 minutes, with a two-minute warm-up and three-minute cool down.

The final group was assigned to interval training, using the most abbreviated workout yet to have shown benefits. Specifically, the volunteers warmed up for two minutes on stationary bicycles, then pedaled as hard as possible for 20 seconds; rode at a very slow pace for two minutes, sprinted all-out again for 20 seconds; recovered with slow riding for another two minutes; pedaled all-out for a final 20 seconds; then cooled down for three minutes. The entire workout lasted 10 minutes, with only one minute of that time being strenuous.

Both groups of exercising volunteers completed three sessions each week for 12 weeks, a period of time that is about twice as long as in most past studies of interval training.

By the end of the study, published in PLOS One, the endurance group had ridden for 27 hours, while the interval group had ridden for six hours, with only 36 minutes of that time being strenuous.

But when the scientists retested the men’s aerobic fitness, muscles and blood-sugar control now, they found that the exercisers showed virtually identical gains, whether they had completed the long endurance workouts or the short, grueling intervals. In both groups, endurance had increased by nearly 20 percent, insulin resistance likewise had improved significantly, and there were significant increases in the number and function of certain microscopic structures in the men’s muscles that are related to energy production and oxygen consumption.

There were no changes in health or fitness evident in the control group. . .

The research was done by scientists at McMaster University in Hamilton, Ontario.

Written by LeisureGuy

27 April 2016 at 4:18 pm

Slime molds and slant razors

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I periodically get into a discussion about whether slant razors work—well, obviously they work, but whether the slant of the blade has anything to do with the ease of cutting and the high efficiency of a good slant. I think it does, and the main counter-argument (so far as I can understand it) is “The slant cannot make a difference in cutting ease because the slant is too small to make a difference.” I interpret this to mean that the person making the statement is, in effect, “I don’t see how such a small slant could make a perceptible difference.”

But of course we fairly often observe phenomena that we can explain how they’re happening even though it is obvious that they are happening. Indeed, that’s one common way for science to advance. As Isaac Asimov commented, the statement that accompanies a major scientific discover is not “Eureka!” but “Huh! That’s odd.”

For example, if one were told that a one-celled lifeform without a brain or nervous system was capable of learning, he would probably deny it. And if it were demonstrated that, yes, the single cell can indeed learn, I think most would say, “I don’t see how.” But the demonstration is fairly solid, and even though we don’t (yet) understand exactly how, we have to recognize that learning does occur. And (so far as I’m concerned) even though we don’t see how a small slant in the blade can make a razor better, it is my experience that it does—that is, with equally well-designed razors, the one with a slanted blade cuts more easily and efficiently, in my experience.

Regarding the observation that slime molds learn, read this article in the LA Times by Amina Khan:

You don’t need a brain to learn something new – not if you’re a slime mold, anyway. Scientists who watched Physarum polycephalum search for food found that the slime mold could learn to ignore certain chemical threats.

The findings, described in the Proceedings of the Royal Society B, contradict the idea that learning always requires neurons, and may shed light on the early evolution of learning in living things.

Learning and memory are essential tools in this critter-eat-critter world; they allow animals to use information from their past experiences to make better decisions in the present. And for a long time, scientists thought only creatures with nerves and noggins truly had access to these special skills.

“We usually think of learning as a trait that is limited to organisms with brains and nervous systems,” the study authors wrote. “Indeed, learning is often equated with neuronal changes such as synaptic plasticity, implicitly precluding its existence in non-neural organisms.”

But that view has been changing in recent years as scientists have been confronted with the astounding abilities of brainless creatures. Take the slime mold, for example. It’s an amoeba-like, single-celled organism filled with multiple nuclei, part of a primitive lineage that’s been munching on bacteria, fungi and other forest detritus for hundreds of millions of years. And yet, this very simple living thing manages all kinds of intellectual feats. . . . [examples in article of surprising slime-mold feats. – LG]

Cunning as the slime mold may seem, can it actually learn? To find out, scientists at Toulouse University in France tested slime molds’ behavior in the lab, focusing on a very basic form of learning: habituation, when a living thing’s behavioral response decreases to a repeated stimulus — whether good or bad — over time.

The researchers placed the slime molds near a bridge; across the bridge, they placed a delicious pile of oats. Some of the bridges were made of plain agar gel, and the slime molds crossed those with ease. But for other slime molds, the scientists left an unpleasant surprise: bitter-tasting quinine or caffeine, which in large amounts can be toxic for some creatures.

At first, there was a clear difference between the slime molds with a bitter bridge and those without. With a plain agar bridge, the slime molds sped across and pounced on the oats in about an hour. With quinine, slime molds entered the bridge only after two and a half hours, and it took them four hours in all to cross. On caffeine-covered bridges, the slime molds took almost five hours to enter the bridge but then quickly sped across.

For both bitter bridges, the slime mold didn’t simply move its body across; it extended a long, thin tendril across the bridge, minimizing the area that touched the surface, as if it were trying to tiptoe over hot sand. When it reached the oats, it quickly moved the rest of its body over through that tendril and over to the oats. Once the slime mold had consumed the food source, the scientists connected it to another bridge, with a fresh food source at the other end. If the slime mold wanted its next meal, it would have to brave the bridge again.

Here’s the strange thing: The slime molds dealing with the alarmingly bitter compounds seemed to get used to it, realizing that it wasn’t a threat. With every bitter bridge they crossed, they moved more quickly and easily and seemed less concerned with minimizing their “footprint” that touched the surface. By the sixth day, Boisseau said, the slime molds were acting essentially as if the bitter compounds were not there.

So had the slime molds learned anything in the first place? Or was it simply that their receptors became dulled to the chemical onslaught, or that they grew too tired to keep their bodies away from the bitter compounds?

To make sure, the scientists took slime molds that had learned to cross a quinine bridge without flinching and exposed them to caffeine. After all, if the slime molds were simply just tired from the effort of carefully crossing the bridge, they should react to the caffeine the same way they did to the quinine, with nonchalance. But no dice: Slime molds that had been habituated to the quinine reacted with extreme prejudice to the caffeine. The slime molds, it seemed, really had learned a specific reaction to a specific chemical.

The researchers also gave the slime molds a couple of days of rest, allowing them to potentially “forget” this lesson. Sure enough, after a couple of days away from the bitter compounds, the slime molds reacted to a quinine or caffeine-laced bridge as if they had never touched one before. They had forgotten that the bitter bridges were safe.

“They were behaving as if it was the first day they had ever encountered the bitter compound,” Boisseau said.

How these critters manage this feat is still a great mystery to scientists, Boisseau said, and will have to await future study. But it does show that we may have to start thinking about the nature of this particular aspect of intelligence in a very different light. . .

Continue reading.

More in these articles:

In Motherboard, by Sarah Emerson: “Scientists Think Intelligent Life Could Have Evolved Before Brains

In the Washington Post, by Fred Barbash: “Slime mold: The next wet thing in computing?

In the NY Times, by Andrew Adamatzky and Andrew Ilachkinski: “The Wisdom of Slime

I sure don’t see how the slime mold does it, but I can see that it does. And I don’t understand how the slight slant adds a perceptible advantage, but I experience that it does—and so do others.

Written by LeisureGuy

27 April 2016 at 1:13 pm

Posted in Science, Shaving

A Study on Fats That Doesn’t Fit the Story Line

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Aaron Carroll reports in the NY Times:

There was a lot of news this week about a study, published in the medical journal BMJ, that looked at how diet affects heart health. The results were unexpected because they challenged the conventional thinking on saturated fats.

And the data were very old, from the late 1960s and early 1970s.

This has led many to wonder why they weren’t published previously. It has also added to the growing concern that when it comes to nutrition, personal beliefs often trump science.

Perhaps no subject is more controversial in the nutrition world these days than fats. While in the 1970s and 1980s doctors attacked the total amount of fat in Americans’ diets, that seems to have passed. These days, the fights are over the type of fat that is considered acceptable.

Most of our fat comes from two main sources. The first is saturated fats. Usually solid at room temperature, they’re in red meat, dairy products and partly in chicken. The second is unsaturated fats, usually softer and more liquid at room temperature. They’re in fish, nuts and vegetable oils. Many doctors and nutritionists still argue, quite strongly, that the key to health is to emphasize the unsaturated fats. Others believe that’s misguided.

This week’s news came to us by way of a randomized controlled trial, which I’ve argued repeatedly is the best kind of study to determine how one thing causes another.

The Minnesota Coronary Experiment was a well-designed study that was conducted in one nursing home and six state mental hospitals from 1968 to 1973. More than 9,400 men and women, ages 20 to 97, participated. Data on serum cholesterol were available on more than 2,300 participants who were on the study diets for more than a year.

At baseline, participants were getting about 18.5 percent of their calories from saturated fat, and about 3.8 percent from unsaturated fats. The intervention diet was considered a more “heart healthy” one. It encouraged a reduction in the amount of calories from saturated fats (like animal fats and butter) and more from unsaturated fats, particularly linoleic acids (like corn oil). The intervention diet lowered the percent of calories from saturated fats to 9.2 percent, and raised the percent from unsaturated fats to 13.2 percent.

Continue reading the main story

The average follow-up for these participants was just under three years. In that time, the total serum cholesterol dropped significantly more in those on the intervention diet (-31.2 mg/dL) than in those on the control diet (-5 mg/dL).

There was, however, no decreased risk of death. If anything, there seemed to be an increased mortality rate in those on the “heart healthy” diet, particularly among those 65 years and older. More concerning, those who had the greater reduction in serum cholesterol had a higher rate of death. A 30mg/dL decrease in serum cholesterol was associated with a 22 percent increase in the risk of death from any cause, even after adjusting for baseline cholesterol, age, sex, adherence to the diet, body mass and blood pressure.

Of course, this is only one study. It involved only institutionalized patients. Only about a quarter of the participants followed the diet for more than a year. The diets don’t necessarily look like what people really ate, then or now. But this is still a large, randomized controlled trial, and it’s hard to imagine we wouldn’t at least discuss it widely.

Moreover, the researchers conducted a meta-analysis of all studies that looked at this question. . .

Continue reading.

Written by LeisureGuy

27 April 2016 at 9:07 am

The idiot’s guide to low-carb high-fat eating

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I keep my net carbs (total carbs minus dietary fiber) below 50g/day, and it has put my type 2 diabetes into remission. The calories lost by restricting carbs to that extent are replaced by eating more fat— protein intake stays the same. The high-fat diet staves off hunger quite well—fat in general is more slowly digested than carb and in particular more slowly than refined carbs (sugar, flour products such as bread, pasta, pastries, boxed breakfast cereals, and the like). And the slow digestion prevents insulin spikes.

One still must watch caloric intake, of course, but the absence of hunger pains makes it easier to keep calorie intake reasonable. I’ve lost 20 lbs since the beginning of the year, which amounts to 5 lbs/month, a reasonable rate of loss.

Marika Sboros at FoodMed.net has a post introducing LCHF to those unfamiliar with it:

Some doctors and dietitians still say a low-carb, high-fat (LCHF) diet is dangerours. That’s despite compelling evidence to show both safety and efficacy of LCHF for weight loss, diabetes, heart disease, cancer and even dementia. Some specialists call dementia type 3 diabetes because of its links with diet.

LCHF is a global phenomenon. In South Africa there are three million “Banters”, as fans of LCHF regimens are known in that country. Banting pioneer is UCT emeritus professor Dr Tim Noakes, a world-renowned scientist rated A1 by the National Research Foundation for expertise in both sports science and nutrition. He documented his theories in the best selling The Real Meal Revolution, co-authored with chef Jonno Proudfoot and nutrition therapist Sally Ann Creed that is known as the “Tim Noakes Diet”. Here, in a Q&A, Noakes gives the basics and an Idiot’s Guide to getting started on the LCHF path. First question:

Is LCHF a diet?

No, it’s a lifestyle.

Do you say your diet’s right for everyone – a one-size-fits-all?

There’s no such thing. No diet is right for everyone. LCHF is best for people who have insulin resistance (the inability to tolerate carbohydrate).

Is it correct to call it “Banting”?

It’s probably more correct to call it Ebstein – after German physician Dr Wilhelm Ebstein who first made it high-fat. That was the diet Sir William Osler promoted in his monumental textbook: The Principles and Practices of Medicine published in the US in 1892.

Is LCHF a fad?

Anyone who claims Banting or Ebstein diets are fads knows nothing about medical nutrition history. Nutrition did not begin in 1977 as our students seem to be taught.

Is LCHF the same as Paleo?

The Paleo diet is slightly different; it promotes consumption of only those foods that would have been available to Paleolithic man from about 2.5 million years ago to the Agricultural Revolution starting about 12 000 years ago.  Foods allowed on Banting but excluded on Paleo  are dairy;  fruits are allowed on Paleo but excluded on Banting.

What about Atkins?

The Atkins diet is similar to Banting. Perhaps Banting promotes the use of low-carb vegetables rather more than Atkins did, but the differences are trivial. This shows that (i) first priority, and the commonality of all these diets, is to cut carbs and sugar (and vegetable oils) and (ii) whether you go Paleo or Banting or Atkins is determined by how you respond to the different options in the different diets.  To find the ideal low-carb diet you need to experiment to see how you respond.

Is LCHF extreme?

It depends what you mean by extreme. Moderation is a smug, puritanical word. No mammal eats in moderation. In nature all diets are extreme: lions eat only meat, polar bears mainly fat, panda bears only bamboo shoots, giraffes only acacia leaves.

Is it balanced?

Balance is what has worked for each of these species for millions of years. LCHF can be extremely low in carbohydrate – the one nutrient for which humans have absolutely no essential requirement, but that depends on how sick you are. In 1977, when we were told to eat diets extremely high in carbohydrates, human health started to fail on a global scale.

Your recommended carb range is <200g to <25g, correct? What are the indications?

It depends how insulin resistant you are and how much exercise you do. If you are completely insulin sensitive (that is, you tolerate carbohydrates well, have low fasting blood glucose, insulin and triglyceride concentrations, low small LDL particle numbers; low HbA1c; high HDL-cholesterol concentrations; and absence of fatty liver) and exercise regularly a few hours a week, then it is can be safe to ingest up to 200g carb per day, or at least until your HbA1c rises above 5.5% . That’ll be time to start reducing the carbs.

On the other hand, if you are profoundly insulin resistant with type 2 diabetes, morbidly obese, or with heart disease, cancer or dementia, you’ll probably do best on a very low-carb  diet of about 25 grams carbs per day. This won’t  change even if you do more exercise. Exercise is helpful but doesn’t obviate the need to eat very few carbs, even if you exercise for many hours a week.

What carb-fat-protein ratio is best?

It depends how sick you are. If you’re diabetic, we say 20% to 30% protein, 60% to 70% fat, 5% carbs. The sicker you are, the more fat you need because fat is insulin-neutral. The more insulin resistant you are, the more fat you can eat, because even when the pancreas fails, fat is the only fuel you can metabolise safely without requiring insulin. It’s perfect for blood sugar control.

Any weighing of food on your diet? . . .

Continue reading.

I highly recommend Nina Teicholz’s The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet and/or Gary Taubes’s Why We Get Fat and What to Do About It.

Written by LeisureGuy

27 April 2016 at 7:59 am

Researchers Built a Wind Tunnel to Study Birds and Build Better Drones

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Very interesting article by Louise Matsakis in Motherboard. The article is worth reading, and here’s the video from it:

Written by LeisureGuy

26 April 2016 at 2:01 pm

Posted in Science, Video

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