Hi Vlad:

It seems to me that you've missed the point when you argue about whether the VMN or the arcuate nucleus is the mechanism for the change in appetite. (BTW the wikipedia article you quote doesn't cite the source of the information.) Two sentences beyond the portion you've chosen to highlight and quibble over, Taubes says this (copied and pasted from your own post):

"[I]nsulin secretion in VMH-lesioned animals increases dramatically within seconds of the surgery. The insulin response to eating also goes 'off the scale' with the very first meal. The more insulin secreted in the days after the surgery, the greater the ensuing obesity."

The point of this paragraph is that circulating levels of insulin can now be measured because of new technology, that levels of insulin rise dramatically immediately after the surgery, and that the more insulin is secreted the fatter the animal grows.

Here are a couple of abstracts of studies at the NIH site which seem to indicate that insulin increases hunger and eating:



http://www.ncbi.nlm.nih.gov/pubmed/3894001



http://www.ncbi.nlm.nih.gov/pubmed/6757987

Would you be so kind and tell us where exactly that quote come from? Book, page number, article name, publication name, etc. Thank you.

Edit--- nvm, it's in GCBC page #391, 1st paragraph after the figure showing hormones that regulate fat tissue. I have the book you see.

Let us talk about that paragraph for a moment. Half way, we get this:
"As investigators now reported, insulin secretion in VMH-lesioned aimals increases dramatically within seconds of the surgery."

What this means is that the VMH area of the brain controls insulin secretion, and destroying parts of it will affect insulin secretion.

Continuing with my own half-assed analysis.

"The insulin response to eating also goes "off the scale" with the very first meal."

This means the VMH part of the brain controls insulin secretion, and destroying parts of it will cause insulin secretion to rise disproportionately.

"The more insulin secreted in the days after the surgery, the greater ensuing obesity."

This means obesity grows in proportion to insulin secretion.

"Obesity in these lesioned animals could be prevented by short-curcuiting the exaggerated insulin response -- by severing the vagus nerve, for example, that links the hypothalamus with the pancreas."

This means the VMH part of the brain controls insulin secretion through the vagus nerve. It further means that lowering insulin secretion will reduce obesity.

"Similarly, the hypersecretion of insulin was reported to be the earliest detectable abnormality in genetic strains of obesity-prone mice and rats."

This means more insulin means more obesity. It further means that obesity is not due to overeating, but that overeating is due to obesity.

I have to agree with Costello on all points.


Vlad, I understand that you want to disagree with Taubes on certain points but it's obvious that what he says can be interpreted differently than you do. Please consider finishing GCBC. I am willing to give you a few pointers if you want.

costello22
here is proof enough for you

this and this


Rapid changes in the sensitivity of arcuate nucleus neurons to central ghrelin in relation to feeding status.

http://en.wikipedia.org/wiki/Arcuate_nucleus

M Levac
you are doing the best job presenting GT non sense into something worth responding to.

VMH is not involved in insulin or hunger and obesity at all but another part of hypothalamus called arcuate nucleus . That was just misplaced early thinking that GT used to make some desperate point on insulin.


GT point that insulin goes through the roof is pure nonsense when you consider that insulin and few other hormones get activated by the mere sight or even thought of food when you are hungry in order to prepare yourself for the meal. This is further proof that "controlling insulin" is impossible for a good reason. Also insulin is secreted in pulsatile form which means every 5 minutes or so and it doesn't go off all at the same time for a reason to make it effective of clearing the blood

Vlad, the quote from the Google book is from a psychology book. Are you saying that obesity is a problem of behavior, i.e. we eat too much? Are you saying the solution is to eat less? Are you saying fat tissue is inert, i.e. a big fat garbage dump that has no say on what happens to its content?

It's very ironic that you would use hormones in an attempt to contradict anything Gary Taubes said. The biggest point Gary Taubes makes is that obesity is controlled by hormones, i.e. a physiological problem. It makes very little sense to attempt to show that obesity is a psychological problem (i.e. we eat too much) by quoting stuff that talk about hormones that control hunger. It's like you're trying to tell us that this car's mechanical problems is due to driver error by pointing out all the mechanical systems failures the car suffered.

Fat tissue is controlled by hormones. So is hunger. They are both physiological problems. In fact, our behavior is a physiological problem because the brain is made of flesh, just like the rest of our body. The brain is controlled by hormones. Muscles, organs, fat tissue, all tissues are controlled by hormones.

It's entirely possible that as we grow fatter, fat cells send a signal to the brain "eat more". That's probably how we learned about ghrelin and leptin. We probably noticed a correlation between mysterious hormones not yet identified and fat tissue mass. And wouldn't you know, there is a correlation between ghrelin, leptin and fat tissue mass. Very obese people need to be injected with massive doses of leptin compared to leaner counterparts: They are leptin resistant. Obese people probably have loads of ghrelin floating around as well since ghrelin induces hunger. But you probably know all this since you're the one quoting stuff about those hormones anyway.

I don't see how anything you wrote so far in this forum contradicts or refutes anything Gary Taubes said or wrote. If anything, your arguments about hormones support and confirm Taubes' argument that obesity is a physiological problem of excess fat accumulation.

Vlad, you quoted Wikipedia about arcuate nucleus. In that quote, we can read:

But now you tell us that:

I'm sorry Vlad, I can't follow your arguments when they contradict themselves like that. If there's anybody that's not making any sense right now, it's certainly not Taubes.

the reason why insulin got such an undeserved bad rap was probably because of the so called insulin shock therapy


First of all it was criminal to take insulin in one huge dose when naturally insulin is released in pulsatile form as I've shown in the other post. What happens obviously is that this lowers blood sugar too much to induce coma no less which obviously releases adrenalin and cortisol which pump the blood sugar back up by breaking all soft tissue and producing obesity as a stress response . This really says not to mess with the natural ways of the body , nothing more or less.

You are arguing that controlling insulin is impossible due to our ability to respond to external stimuli that can affect insulin. That makes no sense at all. If we can affect insulin with external stimuli, then this is proof that we can control insulin by controlling these external stimuli.

The reason insulin gets a bad rap is because you keep calling it "evil" and now "criminal". I never call it evil or anything like that. Nor did Taubes. I, like Taubes, merely understand its role in obesity and there's nothing moral about that.

Perfect sense, one area is involved in food intake , the other area in play and sex behaviour.

Yeah right, giving people supraphysiological amounts of a hormone that would never happen naturally and that would kill them is indeed criminal . Insulin shock therapy killed many people which is the reason why it stopped I presume. If you follow Taubes though , I guess you can justify that non sense like all the rest of it

Play and sex behavior is also controlled by hormones, i.e. dopamine and endorphins and testosterone/estrogen. So what's your point?

Making a moral judgment by calling insulin "criminal" and "evil" has no bearing on the nature of insulin. Insulin does what it does because that's how physiology works. Insulin is amoral, i.e. it has no moral code of behavior.

Insulin is secreted everytime you eat a meal and in a pulse form every 5 minutes or so . Insulin is synthesized and released from pancreatic beta cells
in response to elevations in plasma glucose concentrations,
specific amino acids (e.g. arginine), potassium and parasympathetic nervous system tone. Insulin is too important to be "controlled" and is largely automatic and can be triggered by the mere thoughts .

I have called insulin shock therapy as "criminal" , don't try to put your words into my mouth or go on some random moralizing