Posted on 07/20/2013 12:28:18 PM PDT by neverdem
Looks like an unbalanced equation to me.
Why, in the olden days, did many people subsist on mainly a hunk of bread in the morning, and a hunk of bread at night with some soup or meat? Throughout history, man has eaten breads. I don’t understand what’s so bad about bread. Without it, it seems to me that humans wouldn’t have fared so well.
"MODERATION IN ALL THINGS."
Actually, the mitochondria can use directly a number of short and medium chain fatty acids. Coconut oil, for instance, has a few.
Human breast milk is loaded with fats and has a lot of the MCFA’s.
Remember, babies can’t hardly digest anything at all till they are weaned.
I'll say it again - there is no requirement for dietary carbohydrates in humans.Incorrect.
Given that there have been a number of native cultures that subsisted on zero-carb diets for thousands of years, you should provide more than a bare assertion, if you want to convince...
). The Effects on Human Beings of a Twelve Months' Exclusive Meat Diet
Your Brain on KetonsThe brain is one big glucose sucking machine.
And now let's really get down to the mitochondrial level. Mitochondria are the power plants of our cells, where all the energy is produced (as ATP). Now, when I was taught about biochemical fuel-burning, I was taught that glucose was "clean" and ketones were "smokey." That glucose was clearly the preferred fuel for our muscles for exercise and definitely the key fuel for the brain. Except here's the dirty little secret about glucose - when you look at the amount of garbage leftover in the mitochondria, it is actually less efficient to make ATP from glucose than it is to make ATP from ketone bodies! A more efficient energy supply makes it easier to restore membranes in the brain to their normal states after a depolarizing electrical energy spike occurs, and means that energy is produced with fewer destructive free radicals leftover.
What does it all mean? Well, in the brain, energy is everything. The brain needs a great deal of energy to keep all those membrane potentials maintained - to keep pushing sodium out of the cells and pulling potassium into the cells. In fact, the brain, which is only 2% of our body weight, uses 20% of our oxygen and 10% of our glucose stores just to keep running. (Some cells in our brain are actually too small (or have tendrils that are too small) to accommodate mitochondria (the power plants). In those places, we must use glucose itself (via glycolysis) to create ATP.) When we change the main fuel of the brain from glucose to ketones, we change amino acid handling. And that means we change the ratios of glutamate and GABA. The best responders to a ketogenic diet for epilepsy end up with the highest amount of GABA in the central nervous system.
One of the things the brain has to keep a tight rein on is the amount of glutamate hanging out in the synapse. Lots of glutamate in the synapse means brain injury, or seizures, or low level ongoing damaging excitotoxicity as you might see in depression. The brain is humming along, using energy like a madman. Even a little bit more efficient use of the energy makes it easier for the brain to pull the glutamate back into the cells. And that, my friends, is a good thing.
Let me put it this way. Breast milk is very high in fat. Newborns spend time in ketosis, and are therefore to some extent ketoadapted. Breast milk is also high in sugar, but babies' brains are so big they can handle a lot more sugar than us full-grown folks. Being ketoadapted means that babies can more easily turn ketone bodies into acetyl-coA and into myelin. Ketosis helps babies construct and grow their brains. (For those interested in nitty gritty details - babies are in mild ketosis, but very young babies seem to utilize lactate as a fuel in lieu of glucose also - and the utilization of lactate also promotes the same use of acetyl-CoA and gives the neonates some of the advantages of ketoadaptation without being in heavy ketosis.)
We know (more or less) what all this means for epilepsy (and babies!). We don't precisely know what it means for everyone else, at least brain-wise. Ketosis occurs with carbohydrate and protein restriction, MCT oil use, or fasting. Some people believe that being ketoadapted is the ideal - others will suggest that we can be more relaxed, and eat a mostly low sugar diet with a bit of intermittent fasting thrown in to give us periods of ketosis. (A caveat - I don't recommend intermittent fasting for anyone with an eating disorder without some extra support and consideration). Ketosis for the body means fat-burning (hip hip hooray!). For the brain, it means a lower seizure risk and a better environment for neuronal recovery and repair.
Thanks so much for posting this.
Bookmarked.
Why, in the olden days, did many people subsist on mainly a hunk of bread in the morning, and a hunk of bread at night with some soup or meat?
Because it was what they had. That doesn't mean that it was optimal.
Neolithic agriculturalists were on average six inches shorter than their paleolithic hunter/gatherer ancestors, and had much worse health and bone structure.
Longevity & health in ancient Paleolithic vs. Neolithic peoples
In fact, the average height of paleolithic man was a full inch taller than the modern american.
Of course, paleolithic hunting practices could not sustain neolithic population densities, let alone modern.
>>Burning fat is aerobic, burning sugar is anaerobic.
“Fat burns in a carbohydrate flame.”
Been 30 years since I took exercise physiology, but looks like that’s still the case.
Carbohydrate management is essential to avoiding “bonking” in endurance events. I can maintain a 75% of Max HR continuous pace for about two hours on just water. Efforts longer than that require carb replenishment.
Also, the primary fuel for the brain is glycogen. (sugar).
Got Gluconeogenesis?
http://en.wikipedia.org/wiki/Gluconeogenesis
>>Throughout history, man has eaten breads.
And starchy roots and fruits, including squash.
Big difference between those, which are COMPLEX carbohydrates that require digestion, VS refined sugar (and worse, liquified sugar) that goes straight into the bloodstream and hammers the endocrine system.
[The notion that cells need free glucose to burn is false. Most cells do very well burning fat.]
What’s your Marathon PR?
Just WHERE, in the bible, can this be found?
Of COURSE?
WHY not?
I don't know. I don't run marathons. And doubt that the great majority of humankind ever has or will push their bodies to such unnatural extremes. My aim is good health, not world-class sports performance.
But I will tell you this. Before embarking on a high-fat/low carb diet. I was 10-15 lbs overweight and took blood pressure medication. I also had to avoid salt. My endurance on hot days was nil. I couldn't mow the lawn in summer without wilting.
Now, my weight dropped 15 lbs. My blood pressure dropped back to 115/70. I stopped the medication. My fasting blood sugar dropped into the 80s. No more mid-morning dizzy spells. No more energy highs and lows. And I take extra salt every day in the form of bouillon drinks. Now I can endure the heat without fading.
So the low-carb business is working for me. And, once again, my aim is a good healthy life without the burden of the widespread metabolic diseases that afflict so much of our population. If I were endeavoring to become an extreme athlete of some sort, then I may need to rethink my nutritional requirements. But is extreme performance really healthy?
Carbohydrate management is essential to avoiding “bonking” in endurance events.
http://www.mensjournal.com/health-fitness/nutrition/paleos-latest-converts-20130618
>>But is extreme performance really healthy?
Depends on what the definition of “extreme is.
The post-modern sedentary lifestyle in the context of caloric overabundance is an unnatural and temporary anomaly.
Migrated lately?
"5. Since oxaloacetate is depleted by gluconeogenesis, Dr. Atkins has postulated that fat calories won’t be utilized in
the absence of carbohydrate. Based on what you now know about the citric acid cycl
e, what is the basic falacy of this hypothesis? (Where does oxaloacetate come from when we break down protein?) "
http://www.med.unc.edu/neurology/files/documents/child-teaching-pdf/CITRIC%20ACID%20CYCLE.pdf
>>But is extreme performance really healthy?
Ask the Talibani who run rings around the Burger-King fodder in the Himalayan foothills that question.
My mistake. However, regardless of its source, it's still very practical.
Aristotle wisely advised moderation in all things. Gluttons and fanatics self-destruct by refusing to make the tradeoffs necessary to lead a good life. “Don’t tell me that I can’t drink and carouse every night and not succeed in my career!” insists the fool. “I can have it all.”
Well, he can’t. No one can. Aristotle wisely advised moderation in all things. Gluttons and fanatics self-destruct by refusing to make the tradeoffs necessary to lead a good life. “Don’t tell me that I can’t drink and carouse every night and not succeed in my career!” insists the fool. “I can have it all.” Well, he can’t. No one can.
Aerobic and Anaerobic metabolisms are not mutually exclusive but, rather, synergistic
The great misunderstanding of the "fat burning zone" myth is the idea that fat burning decreases as intensity increases. The percentage decreases, but that's as a proportion of an increased total. The absolute numbers do not decline.
[myth is the idea that fat burning decreases as intensity increases.]
The relationship between anaerobic high intensity and muscle glycogen isn’t a myth. Nor is the difference between the metabolism of fast and slow twitch muscle fibers.
A 100m sprinter is burning glycogen during the sprint, not fat.
It’s less commonly recognized that “waste” products of high-intensity anaerobic effort (lactic acid for example) are metabolized aerobically.
Thus, the more developed the Aerobic physiology is, the great the Anaerobic effort that can be maintained over a longer period of time.
The associated fitness can be measured by observing recovery HR - as Anaerobic byproducts are metabolized, oxygen debt is reduced, and the HR is reduced to below the Anaerobic Threshold.
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