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6 Eylül 2014 Cumartesi

Another penny drops: Why severe hyperinsulinamia can occur with a small increase in exogenous carbohydrate intake.

This blog post is a result of Vim's comments in the previous blog post. A penny suddenly dropped!
From http://bja.oxfordjournals.org/content/85/1/69.full

Insulin has a Chalonic (inhibitory) action on blood glucose level (via the liver, muscle mass & fat mass), blood FFA level (via fat mass) and blood ketone body level (via the liver).

As mentioned in the comments, GHB has a stimulant effect - up to a certain level of blood GHB. Beyond that level, there's a powerful sedative effect. This is because at low levels of exogenous ketone body input, insulin secretion increases slightly to reduce hepatic ketogenesis.

At a certain level of exogenous ketone body input, hepatic ketogenesis falls to zero and cannot be reduced any further. Any slight increase beyond this point in exogenous ketone body input, results in a large increase in insulin secretion, as the pancreas increases Ketone body-Stimulated Insulin Secretion to maximum in a (failed) attempt to reduce blood ketone body level.

Exactly the same thing happens with exogenous carbohydrate or BHB input.

At a certain level of exogenous carbohydrate input, hepatic glucogenesis falls to zero and cannot be reduced any further. Any slight increase beyond this point in exogenous carbohydrate input, results in a large increase in insulin secretion, as the pancreas increases Glucose-Stimulated Insulin Secretion to maximum in a (failed) attempt to reduce blood glucose level.

13 Ağustos 2014 Çarşamba

Dear ItsTheWoo, how do you do?

This post is attacking what I consider to be faulty reasoning. It's not a personal attack on ItsTheWoo, who I like (even though she drives me up the wall, sometimes!).
From http://hypetrak.com/2011/10/mayer-hawthorne-how-do-you-do-full-album-stream/

See What I believe and what I don't.
The basic The Energy Balance Equation:- Change in body stores = Ein - Eout
For a detailed mathematical analysis of weight change, see Completing the trine: vive la différence!

From Back to black, CIAB, pharmaceutical drug deficiencies & nerds:-
Where body weight is concerned, calories count (but don't bother trying to count them).
Where body composition is concerned, partitioning counts.
Where health is concerned, macronutrient ratios, EFAs, minerals, vitamins & lifestyles count.


The faulty reasoning is in Dear Nigel and other CICO zealots: you are ignorant. Charming!

I'll quote passages from it and refute them, one by one.

  • "With a zero caloric deficit, there is zero weight change"
"FACT: Calories neither determine weight OR body composition with certainty. Nigel / some CICO zealots may agree body composition changes are privy to nutrition, but wt is 100% controlled by calories. This is something they pretty much made up and biological science does not at all support this idea. Calories neither control body composition OR body weight/mass with any certainty. The bulk consumed with fork and spoon does not need to stick on your body in the form of a mass laden tissue, ever."
Calories determine weight change. See Bray et al shows that a calorie *is* a calorie (where weight change is concerned). It would have been nice if Fig. 6 had contained a plot of "Effect of energy intake on change in body weight", but it didn't.
LBM = Lean Body Mass
FM = Fat Mass = Body Fat

Weight change = LBM change + FM change
Weight change varies from ~+3.5kg (@ +2,500kJ/d) to ~+9.1kg (@ +5,900kJ/d).
(Maximum weight increase)/(minimum weight increase) = 2.6
(Maximum kJ/day increase)/(minimum kJ/day increase) = 2.36
∴ A calorie IS a calorie (where weight change is concerned).
Insufficient protein can result in loss of LBM (bad).

The main thrust of ItsTheWoo's argument is that inter-personal variations in weight gain from subject to subject, invalidates Bray's conclusion. It doesn't.
Some subjects become more energetic on a 40% caloric surplus, which increases their NEAT & TEA, which increases their Eout, which reduces their weight gain.
Some subjects don't change their energy on a 40% caloric surplus, which doesn't change their NEAT & TEA, which results in intermediate weight gain.
Some subjects become less energetic on a 40% caloric surplus, which decreases their NEAT & TEA, which decreases their Eout, which increases their weight gain.

I believe that the Insulin Sensitivity (IS) of the subject determines which category they fall into and by how much. The higher the IS, the higher the energy, as high IS results in low serum insulin, which minimises sedation. Energy Balance always applies.

I've never stated that Calories exactly determine weight change. That's a strawman.
I've never stated that Calories determine body composition. That's a strawman.

  •  " Every subject [in bray's overfeeding study] gained weight (mostly fat mass) during the 40% energy excess overfeeding period. "
"Again, making crap up. There is NO RULE IN BIOLOGY which states all consumed energy must be retained as body mass. Indeed most typical people gain fat during overfeeding (with great resistance/inefficiency of fat gain), but it is indeed possible to hardly gain any or none at all as in constitutional thinness. What happens during calorie consumption among different people (and perhaps, different DIETS and different TIMES and different ENDOCRINE situations...) is a wild card determined by the biology i.e. neuroendocrine functions of the animal in question. There is NOTHING about physics which reflects / informs physiology other than the basic fact the latter exists within the former (which, again, tells us NOTHING ultimately). How organisms process consumed nutrition is not a physics question. There is no freakin' law of physics or physiology for that matter which states nom nom time = thigh chub. You don't have to wear that pizza as a popeye's muscle or as a shelf butt."
Somewhere within all of the irrelevant waffle about rules & laws, ItsTheWoo raises an interesting point. Although a caloric surplus is always required for weight gain, eating more Calories can sometimes result in zero weight gain. How so? From ItsTheWoo's link:-
"Conclusion: This data is the first to demonstrate a resistance to weight gain in constitutional thinness (CT) population in response to 4-week fat overfeeding, associated with an increase in resting energy expenditure and an emphasised anorexigenic hormonal profile.
In CT people, their energy expenditure increases in line with their energy intake. Therefore, even though they're eating more Calories, there's no caloric surplus, therefore there's no weight gain. Energy Balance always applies.

  • "Yes, kcals do get wasted. You don't understand things quantitatively i.e. how many kcals get wasted."
"I know anxious/obsessional people like the safe feeling of balancing calories. The fact reality is more complex and you can't just enter things in a phone app and be ASSURED of what is going on in your body, doesn't invalidate the truth of the fact metabolic reactions are more complex THAN CALORIES.

Just because it is *impossible* for a reasonable free living human to quantify all of the metabolic, endocrine, nervous system factors influencing adipocyte growth changes does not mean they don't fucking exist."
ItsTheWoo left out my calculations. Here they are:-"if I eat 2000 calories of a ketogenic diet in 3 hrs, most of it is wasted as heat, physical energy (I know, because I am EXTREMELY warm/energetic) and then the rest of time i am using a relatively greater percent of stored fat."
Do you know at what rate you're burning-off extra energy intake as heat energy output when you're "EXTREMELY warm/energetic"? Here's an estimate:-
If the mean TEF for your meal is 11% (assuming your meal is 50%E protein & 50%E fat), that's 220kcals (921kJ) "wasted" as heat energy. That'll make you feel EXTREMELY warm, as 220kcal raises the temperature of 57kg of water (your body) by 3.84°C.

A 2,000kcal meal (a whole day's worth of food) takes a lot longer than 3 hours to digest & absorb. I'll guesstimate it as 24 hours. 921kJ of extra heat power over the course of 24 hours = 10.7W, which is an increase of 17.7% over your normal Metabolic Rate of ~60W heat power (~1kcal/minute).
It's easy to "prove" something by being vague. That's PSEUDOSCIENCE. I do science. If you do the maths, you can see that, of the 2,000kcal ketogenic meal, most of it isn't wasted as heat, because if most of it is wasted as heat, ItsTheWoo would spontaneously combust!

  • "Dr. Robert C. Atkins made the same fundamental cock-up when he said that humans pissed-out loads of kcals of ketones each day, giving a Metabolic Advantage to ketogenic diets."
"1) The advantage of a ketogenic diet (non-fasting) does exist, so it's not a 'cock up", even if his mechanism was wrong.
2) If atkins was wrong (you pee out all LCHF food) who cares? That was 30+ years ago. He was a cardiologist who observed a VLC diet made him slim. He used his medical education to hypothesize a reason why. His hypothesis was wrong, but his observations were right. This happens all the time in science or basic human reasoning; make observations, form hypothesis. The hypothesis may be wrong, the findings are STILL RIGHT (i.e. low carb diets DO make slim, just not via peeing away ketones)."
1) There is no Metabolic Advantage to ketogenic diets. See http://www.jbc.org/content/92/3/679.full.pdf
2) Atkins' observations were wrong. See The Battle of the Diets: Is Anyone Winning (At Losing?)
a) Low-Carb diets work better than High-Carb diets for people who are Insulin Resistant.
b) Low-Carb diets work worse than High-Carb diets for people who are Insulin Sensitive.
c) Low-Carb diets work the same as High-Carb diets for everybody in Metabolic Ward Studies.
If there's a Metabolic Advantage to ketogenic diets, they would work better than high-carb diets all the time. They don't. See How low-carbohydrate diets result in more weight loss than high-carbohydrate diets for people with Insulin Resistance or Type 2 Diabetes for my hypothesis, which explains a), b) and c).

30 Temmuz 2014 Çarşamba

The Ketogenic Diet: Uses in Epilepsy and Other Neurologic Illnesses.

Fools claim that I am anti-ketogenic diets. Am I ****! beta-Hydroxybutyric acid has its uses...
From http://www.fuelforthought.co/the-ketogenic-diet-uses-in-epilepsy-and-other-neurologic-illnesses-2/

From The Ketogenic Diet: Uses in Epilepsy and Other Neurologic Illnesses:-

"Inconsistencies in studies attempting to correlate seizure protection with levels of ketone bodies suggest that another mechanism may be involved in the diet’s beneficial effects on seizures. Several mechanisms have been proposed, including changes in ATP production making neurons more resilient in the face of metabolic demands during seizures; altered brain pH affecting neuronal excitability; direct inhibitory effects of ketone bodies or fatty acids on ion channels; and shifts in amino acid metabolism to favor the synthesis of the inhibitory neurotransmitter GABA."

GABA is an interesting neurotransmitter, as it's the chief inhibitory neurotransmitter in the mammalian central nervous system.

I know of two other substances that enhance GABA's effects - Alcohol and Benzodiazepines.


In conclusion:

I'm in favour of ketogenic diets under medical supervision, as therapy for neurologic conditions etc.

I'm not in favour of ketogenic diets under lay supervision, as a supposed aid for weight loss.

16 Temmuz 2014 Çarşamba

Jumping through hoops, and my Blog List.

I'm seeing a curious thing. The VLC "camp" seems to be "jumping through hoops" to prove a point.
From http://davidbressler.com/2013/08/26/easier-harder/

From Neuron fuel and function (emphasis & formatting, mine):-
"Ketones and lactate do not drive reverse electron flow through complex I. Glucose can. Palmitate certainly can. What you want from a metabolic fuel depends on the remit of your cell types. Neurons within the brain preserve information by their continued existence.

This is best done by burning lactate or ketones. NOT glucose and, of course, not FFAs.

Anyone who claims that glucose is the preferred metabolic fuel of the brain has not though (sic) about what a neuron has to do and what an astrocyte actually does do. Or much about the electron transport chain."

Basically, glucose is bad mmm-kay. Also, anyone who claims that glucose is the preferred metabolic fuel of the brain is a dumb-ass. Damn our livers & kidneys churning out glucose! Are they trying to kill us?

∴ Carbohydrates are bad and must be avoided at all cost! This, of course, is utter nonsense.

Glucose can drive reverse electron flow through complex I. Can means that it's possible. Is it probable?

On a hypercaloric Western diet of excessive crap-in-a-bag/box/bottle, yes.

On a Kitavan diet of ~70%E from tubers, no.

On a diet of Basmati rice & beans, no.

On a diet of whole fruits, no.

See also Another crash and burn on low carb paleo and CrossFit. Enough of the 'carbs are evil' nonsense. Carbphobia is hurting a lot of people.

I have a list of blogs that I read on a regular basis. As a result of the bad science & cherry-picking displayed in various VLC blogs, I have deleted them from my Blog List.

See also Guest post: Denialism as Pseudoscientific Thinking.

7 Temmuz 2014 Pazartesi

Why Calories count (where weight change is concerned).

I have to add the words "where weight change is concerned", as calories have little to do with body composition or general health (unless somebody becomes morbidly obese).
From https://docs.google.com/file/d/0Bz4TDaehOqMKSXZHUUVxWnl5VTQ/edit?usp=sharing

Arguments used by Calorie Denialists include:-

1) Calories don't count because the human body isn't a Bomb Calorimeter and treats different macronutrients differently.
 
100g of liquid paraffin burns in a Bomb Calorimeter, yielding 900kcals. In a human, it passes through completely undigested. Ah-ha!, I hear you saying. This proves that the Energy Balance Equation is invalid. Uh, nope!

Calories in = Calories entering mouth - Calories exiting anus

As 100% of liquid paraffin calories entering the mouth exit the anus, Calories in = 0

This is why Sam Feltham's "Smash the Fat" "experiment" is nonsense. A high percentage of the large amount of raw almonds he ate would have exited his anus incompletely chewed, undigested & unabsorbed.

See the picture above? In the late 1800's, W.O. Atwater established Atwater Factors (3.75kcals/g for digestible Carbohydrates, 4kcals/g for Proteins, 5kcals/g for Ketones, 7kcals/g for Alcohols & 9kcals/g for Fats*) using Human Calorimeters, not Bomb Calorimeters. Atwater Factors are pretty accurate.

*Fats containing different fatty acids have slightly different kcals/g. Fats containing long-chain fatty acids are 9kcals/g. Fats containing medium-chain fatty acids e.g. coconut oil are ~8kcals/g.

For more information, see Calories ...


2) Calories don't count because Dietary Efficiency varies for different macronutrients.

Uh, nope! The Heat Power generated by the body is regulated by a NFB loop involving the Hypothalamus, Pituitary, Thyroid Axis, also Uncoupling Proteins (UCP's), also shivering, so as to maintain a body temperature of 37°C ±3°C. If this wasn't the case, different amounts & types of foods (also, changes in ambient temperature & clothing) would cause large variations in body temperature resulting in death, as the enzymes in our bodies function correctly over a limited range of temperatures.

Heat Power generated by the body (W) = Temperature difference between the body & ambient (°C) divided by Thermal resistance between the body & ambient (°C/W)

∴ Dietary Efficiency is irrelevant.