My Crackpot Theory RE: The Vagus Nerve

[lessnless 1]

For a while now, I've been trying to determine the reason for the difference between my pre-op and post-op satiety levels. First off, "full" and "sated" are two different feelings:

Full: I could eat more, but I ran out of room

Sated: ick, I'm done, take it away

Post-op, when I'm sated, I can't even look at food. Even the smell of food changes. It's dramatic--like the difference mentally between food on the counter and food in the garbage bin. It was edible, but now it's not.

I eat smaller amounts than ever before, I'm never full (overstuffed), and yet I'm completely satisfied. Is this what everyone else feels? It's like a freakin' drug. I catch myself "playing with my pouch"--I drink a cup of warm tea quickly, then bliss out for an hour.

Pre-surgery, I only had this sated/happy/sleepy feeling after the annual binge-feasts (Thanksgiving and Christmas), and it was offset by the misery of being full/bloated/stuffed. The rest of the year, I could eat a burger/fries/coke and an hour later I'd be ready for another meal. Not hungry, really, but I could never feel my last meal in my gut.

I used to say, "Doesn't matter what I eat--it's all Chinese to my stomach. An hour later, and it's hungry again..."

Pre-surgery, the idea of a 500-calorie day ranked right up there with a 26-mile marathon---torture! If you'd told me that I would have 500-calorie days without hunger, I'd have wept for joy.

---- So, here's my CRACKPOT thinking:

• Does the route the vagus nerve takes across/around the stomach and esophagus affect how much food is required to feel sated?
  
• Did I overeat because food was not pushing against the right nerve at the right time?
  
• Are the obese just "anatomically challenged"?

I started thinking about this after I read a study where they implanted a pacemaker-like thingy (I'm so technical) to stimulate the vagus nerve and control severe depression with suicidal urges.

Are humans really that simple? That unevolved? A full belly, and all's right with our world?

HHHHMMMMMMMMMMmmmmm.....

Or, rather,

UUUUUUUUUUUUMMMMMMMMMmmm...

...

...

[Daisalana 33]

Just curious, I went to look up info on Vagus nerve. I've heard something about this, but didn't know the name of it.

So anyway, in a nutshell nothing shows the Vagus nerve doing anything about hunger, and here's the wikipedia entry

Vagus nerve - Wikipedia, the free encyclopedia

Doesn't mention anything about it being a trigger for fullness. Is it possible you have the wrong name? I actually wanted to read up on this stuff, but didn't know the name of it..

[lessnless 1]

COOL Link!

Did you read this part?

Vagotomy (cutting of the vagus nerve) ... currently being researched as a less invasive alternative weight loss procedure to gastric bypass surgery[2]. The procedure curbs the feeling of hunger and is sometimes performed in conjunction with putting bands on patients's stomachs, resulting in average weight loss of 43% at six months with diet and exercise.

[Daisalana 33]

Obviously not! I skimmed through and didn't see anything about it having to do with the stomache (it mentions it connects at the abdomen at some point).

Now I see, wish it had more info. I was hoping to see pics of where it hits the stomach.

[new_me_2008 1]

Last July I was in North carolina for business and there was an article in the local paper about lab band and the vagus nerve (I think that is what they called it) the study involved 'regular' lap band patients and while in surgery they actually 'snipped' the nerve reducing its ability to send a 'hungry' signal to the brain.

The results were not published yet but they profiled one lady who had the procedure and was doing well - although now that I have been through this myself it seems like she lost at a 'normal' rate. She did discuss her complete lack of desire to eat - which is probably where the nerve thing comes in.

The article was great to read - I actually cut it out, brought it home and then held on to it for 3 months until I got the nerve (no pun intended) to discuss with my husband. Two weeks later I was in surgery (self pay).

LOVE the band - and not hungry!

[lessnless 1]

Here's another Link:

Universe Magazine - Knowing When to Stop Story

and another:

Treatment of obesity by bilateral vagus nerve stimulation - US Patent 6587719

and another:

Vagus Nerve Stimulation May Help Prevent Obesity

""i read. and sometimes it scares me...."" e e cummings

[Daisalana 33]

Might be a psychosis problem of mine, but I try to reason why something would or would not work.

And this nerve is one of those things I wanted to play with.

It's stupid stuff I do, like.. if I chew the crap out of a chewable Vitamin I think it will absorb better.. or, if I drink something cold my stomach will shrink and I can eat less, etc. So I thought maybe if I eat a certain way, I can hit the nerve. Just stuff I do out of boredom.. desperation..play with my 2nd calling to be a scientist.. I dunno.

[Catalystmb 2]

Laura,

Here is some info:

Pathophysiology of the Digestive System - Pregastric Digestion

The reason we(the obese) override even the vagus nerve is not known.

Too many other factors are in play; hormones(insulin, leptin, cholecystokinin), environment, and habit.

How many of us have eaten PAST that obvious signla to stop, I know I have.

I think we, well, I eat/ate too quickly. If I slowed down to the pace the band will force me I might "HEAR" that signal.

[Daisalana 33]

That's an interesting read!

Never eat a live mole! This seagull did, the mole tried to tunnel out and they both died. OH DEAR.

[travelgirl 3]

Faithmd posted a very interesting article (with pictures!!!!) on this very subject here somewhere......I'll see if I can find it, and I'll post the link or the article if I can.

[travelgirl 3]

I FOUND IT!!!!!!!!!

Why? Here's an explanation I copied from another WLS support site. It's really good info:

Vagus Nerve:

The Vagus nerve is the longest of the nerves.

Its name is derived from the same root word as "Vagrant," and "Vagabond." (A wanderer; a rover. - Wandering from place to place and lacking any means of support.) From the Middle English vagraunt, probably alteration of Old French wacrant, present participle of wacrer, to wander, of Germanic origin. This "Vagabond" originates in the Cranium but wanders from the brain stem through organs in the neck, thorax and abdomen, all the way to the first third of the colon. It has motor functions in the larynx (voice box), diaphragm, stomach, and heart, and sensory functions in the ears and tongue. It has both motor and sensory functions in the pharynx (sinuses) and esophagus.

Stimulation of the vagus nerve is thought to affect some of its connections to areas in the brain that are prone to seizure activity. It is a "Hot Topic" for research in areas of Depression, Obesity, Epilepsy, and is responsible for some phenomenal sensory and motor responses even without WLS.

Emotions running high? Feeling a lump at the back of your throat that you didn’t put there? That’s the Vagus Nerve at work.

Can’t tickle yourself, except the roof of your mouth? (try it) Because when you try to tickle your armpit-The same nerves that perceive the tickle also "know that it’s coming," and thus the "surprise" aspect that allows "tickling" to occur have been preempted. But- Roof of the mouth? Different selective dumping of info prior to reaching the brain. That’s the Vagus nerve "sharing" some info with sensory and motor controls while "not telling others."

The Vagus nerve is known as a "mixed nerve" meaning it both receives input from the body and sends signals to various muscles and organs of the body. It is the primary nerve of the Parasympathetic Nervous System. It isn’t an even mix, though, about 80% of the axons inside the vagus nerve are sending signals from the body to the brain.

The Vagus nerve consists of Five Components with distinct functions:

--Brancial motor:

(special visceral efferent) Supplies the voluntary muscles of the pharynx and most of the larynx, as well as one extrinsic muscle of the tongue.

--Visceral motor:

(general visceral efferent) Parasympathetic innervation of the smooth muscle and glands of the pharynx, larynx, and viscera of the thorax and abdomen.

--Visceral sensory:

(general visceral afferent) Provides visceral sensory information from the larynx, esophagus, trachea, and abdominal and thoracic viscera, as well as the stretch receptors of the aortic arch and chemoreceptors of the aortic bodies .

--General sensory:

(general somatic afferent) Provides general sensory information from the skin of the back of the ear and external auditory meatus, parts of the external surface of the tympanic membrane, and the pharynx.

--Special sensory:

(special afferent) A very minor component. Provides taste sensation from the epiglottis region.

A simplified explanation to describe "how it works"-

Rather than sending signals out from brain, or bringing sensory info back to the brain, it does both, and it allows "pieces parts" or "stations" along the way to communicate with each other without directly routing through the brain.

It controls much of the movement of the mouth and let’s the esophagus "synch up" with back of tongue motions in order to make swallowing possible. And signals the lower organs of the digestive tract to adjust activity when "food is on the way!"

The Vagus nerve also sends signals to and for those "unconscious" or reflex reactions- such as swallowing when not thinking about it consciously. Often the example given is- "swallowing while sleeping so you don’t drown in saliva." It is associated with Nausea governing factors, Relaxation, (particularly pulse rate) digestion synchronization, etc..

It’s "Fence-sitting" behavior as both Voluntary and Involuntary signal provider, makes it a key factor in most Bio-Feedback processes for reducing stress levels.

How does this effect or associate with Bariatric Post-Op patients?

Signals from the Stomach are "distorted somewhat" and often Disrupted or damaged by the Gastric Bypass. The signals from the pouch often trigger the Vagus nerve to "fire" unique reflex responses. The Vagus nerve transmits the signal to the brain when we are full. It seems to "drop off" some info to other stations on the way to the brain. It is responsible for Diaphragmatic "Dry Heaves" that some experience in the early days following Bariatric Procedures, and longer term is often associated with rapid gastric emptying.

Many Post-ops claim to have their nose start running when they take "that last bite" just before feeling too full. Some experience sneezing or hiccups if they eat a bite too much. Both are actions inextricably bound to Vagus nerve signals. Many claim to get a "runny nose" with one bite too much food for their pouch, and hiccups from eating too fast.

Many Gastric Bypass Post-ops have similar odd signals associated with the connections that the Vagus nerve makes along it’s wandering path.

Complements of DxE...he originally posted this on March 5th, 2007 & I found this very helpful. He is a wealth of information.

[Kat817 19]

At the lap band seminar I attended prior to surgery he mentioned this. Stated that the nerve (s) ending sat at the top of the stomach, which is why we only ever felt full after totally gorging ourselves, and why the old diet guideline of drinking a large glass of Water before we eat, did help to a certain extent, it allowed our food to get to the top of our stomach without eating so much.

He did say that occasionally the mere placement of the band caused enough pressure on the nerve to eliminate the hunger signal. These are the patients we all hear about that have never required a fill. Even then one must be able to tell the difference and deal with the difference between actual hunger and head hunger....as this nerve does nothing for the head hunger. However, for almost all patients, will require fills, which will hold food in our pouch and reach those nerves quickly. And the more efficient our band is working, allowing the food to process very slowly, it will keep us with that sated feeling for longer periods of time than pre band.

I found that amazing information back then, and have seen articles supporting it, I never ever thought though to link them!

He also told us interesting facts concerning the Gruehlin production, being eliminated, or reduced, and how it affects diabetes, that there were studies being conducted world wide, in conjunction with WLS---and those studies just come out in the last few days!!

One of the biggest pushes to banding vs. bypass is all this study---and we are free to pursue any future methods of weight control they discover!!

Kat

[kbinaz 0]

I thought one of the reasons the band worked was because it allowed the food to stay at the point at the top of the stomach where the full signal comes from - I don't know if that is the vagus nerve or what, but that is what I was told. They say obese people don't get that full sensation and I don't remember why- (could have something to do with the largeness of our stomachs not allowing food to ever get to that place where our hunger turns off...) Anyway, sorry to be not such a huge help but I think there is some truth to what you are thinking but I'm not sure it is the vagus nerve. The band is allowing some fullness message to be sent!

[Akbar 0]

Ahh, yes, that initial feeling of restriction was a revelation to me too.

The physiology of appetite is much more complicated than the vagus nerve. Control of body mass, energy expenditure, appetite, are regulated by redundant systems at several levels. It is likely that you will adapt over time (years) to the new signals from your effectively smaller stomach and will not have such a dramatic satiety... but you won't return to your preoperative state. The downside, as you may soon learn, is that if you get too much dense food in your pouch too quickly your stomach will let you know that you have an outlet obstruction - with a feeling of distension, hiccups, increased salivation, maybe even tearing eyes or running nose, and "PB". (If you keep in mind your new small stomach and go slow, though, this is far less likely to happen).