Gastric Juice was: The Evils of Chewing Gum?

[Guest guest]

Hi Martha:

I have some more comments and a thought I wanted to mention, but first,

thanks for the links. I appreciate it and hope to have more time to do more

research.

If it's true that gastric juice is stimulated by smell, taste, etc., then

what about people who work in the food industry all day such as people who

work in restaurants, bakeries, food chemistry, food processing plants, etc.?

Are they continually producing gastric juices in their stomachs all day

long? And if so, how is that different from someone producing gastric

juices in their stomach from chewing gum? Is their environment ruining

their stomachs?

Also, regarding the articles you attached, a couple things stuck out for me

such as the colonic pressure and the pH electrodes on wires. Beaumont did

document that just touching the inside lining of the stomach released " some "

gastric juice, but did not release significant amounts without actual food

touching it. When food touched it, the gastric juice flowed freely. So, it

may be possible that just the electrode wires touching the lining of the

stomach could stimulate just enough gastric juice to make an acid reading

not necessarily caused by the outside stimuli of smell or thought. As far

as the colonic pressure, I question the accuracy of that form of

measurement. In discussing what causes hunger pains, Beaumont explained

that the stomach has lots of tiny papillae. (IIRC, that's what he called

them.) From these papillae is where the gastric juice is secreted in to the

stomach upon contact with food. If there is no food in the stomach, these

papillae become engorged and cause pain, but the gastric juice is not

actually in the stomach cavity. From this it seems that the body does

produce gastric juice without food, but is not necessarily in the stomach.

If food is not introduced in to the stomach after some time, the body

re-absorbs the fluid, and the hunger pains go away. He liken this

phenomenon with the male sperm wherein males get pressure when they have

sperm buildup, but don't necessarily have to release it, and the body will

re-absorb it. This displacement of fluid could possibly cause pressure

changes while there could also be other changes in the system causing

pressure that has nothing to do with the gastric juices. Just a thought.

The kind of study I was wondering if they had done was something similar to

Beaumont's where actual visual observation of the stomach is done. I find

Beaumont's studies compelling because he was able to look directly in to the

stomach without contamination of fluids from other parts of the body. He

could look in there without disturbing other areas which might cause

physical changes to occur in the stomach. He observed digestion from

breakfast, lunch, and dinner checking at various times such as before a

meal, 15 minutes, half an hour, etc. after meals. He was even able to see

when the food decended in to the stomach and feel the pressure of the

suction as the food passed to the small intestines. He would regularly take

out pure gastric juice to replicate digestion outside of the stomach and

compare it to progress inside the stomach to see what affected the processes

of digestion. As you know, he made many more observations. I was wondering

if there were any studies that were able to replicate the conditions of his

experiments. I realize that there probably aren't many (if any at all)

healthy people with holes in their stomachs who would allow digestion

observations. Beaumont's situation was apparently truly unique.

Well, thanks again,

Marla

P.S. I envy your textbook collection! ) Why do you have so many?

----- Original Message -----

From: darkstardog <darkstar@...>

< >

Sent: Wednesday, December 04, 2002 10:16 PM

Subject: Re: The Evils of Chewing Gum?

>

>

> > Thanks, I'm interesting in reading the studies. Do you have any

> references> that I can read? I'm interested how the studies were

> conducted,when and by> whom, and why Beaumont's work seems so

> contradictory. Were they done on> live humans? How? I realize that

> Beaumont only studied one live human, and> it's possible there are

> deviations, so this is interesting to me.

> >

>

> There have to be so many different studies - way too many to list.

> I'm not sure what the best thing would be for you to do to find the

> ones you're interested in. You could try looking up various topics in

> pubmed, or start with a medical physiology textbook. It would help if

> you have a university nearby with medical or biological journals in

> their library.

> Here's the URL for pubmed:

> http://www.ncbi.nlm.nih.gov/entrez/query.fcgi

>

> Here's one pubmed reference I pulled up in a few seconds - it's an

> abstract but unfortunately they don't tell how they did the

> measurements in this abstract and the whole paper isn't online. They

> made some kind of measurement of stomach acid though. Is this the

> kind of thing you're interested in?

>

> " Gastroenterology 1986 Feb;90(2):428-33

> Role of thought, sight, smell, and taste of food in the cephalic

> phase of gastric acid secretion in humans.

> Feldman M, CT.

> The relative importance of thought, sight, smell, and taste of food

> in the cephalic phase of gastric acid secretion has not been studied

> systematically. We found that discussing appetizing food for 30 min

> (without sight, smell, or taste) increased acid secretion from 4 to

> 13 mmol/h in healthy human subjects (p less than 0.001) and also

> increased serum gastrin concentrations significantly

> (p less than 0.02). Discussing food resulted in an acid secretory

> response that averaged 66% +/- 10% of the response to modified sham

> feeding, which activates thought, sight, smell, and taste. Discussing

> topics other than food (e.g., current events, sports) did not

> increase acid secretion significantly. The sight of appetizing food

> (without smell or taste), the smell of appetizing food

> (without sight or taste), or the combination of sight and smell

> (without taste) also increased acid secretion and serum gastrin

> concentrations significantly. However, sight and smell were

> significantly less potent stimulants of acid secretion than sham

> feeding, with responses averaging only 23%-46% of the

> response to sham feeding. These studies indicate that thinking about

> food is a potent stimulant of gastric secretion in healthy humans.

> Moreover, the sight and smell of food increase gastric acid secretion

> and serum gastrin concentrations, probably by provoking thoughts

> related to food. "

>

>

> Here's another one; again the paper isn't available online.

>

> " Gut 1993 Apr;34(4):537-43

> Cephalic phase of colonic pressure response to food.

> J, Raimundo AH, Misiewicz JJ.

> Department of Gastroenterology and Nutrition, Central Middlesex

> Hospital, London.

>

> A cephalic phase of colonic pressure response to food was sought in

> five normal subjects (mean age (22.6) years, 22-24), studied on six

> separate occasions by recording intraluminal pressures in the

> unprepared sigmoid colon. Gastric acid secretion was measured

> simultaneously by continuous aspiration through a nasogastric tube.

> After a 60 minute basal period, one of five 30 minute food

> related cephalic stimuli, or a control stimulus was given in random

> order; records were continued for a further 120 minutes. The cephalic

> stimuli were: food discussion, sight and smell of food without taste,

> smell of food without sight or taste, sight of food without smell or

> taste, and modified sham feeding; the control stimulus was a

> discussion of neutral topics. Colonic pressures were expressed as

> study segment activity index (area under curve, mm Hg.min) derived

> by fully automated computer analysis. Gastric acid output was

> expressed as mmol/30 min. Food discussion significantly (p < 0.02,

> Wilcoxon's rank sum test) increased colonic pressure activity

> compared with control or basal activity. Smell of food without sight

> or taste also significantly (p < 0.03) increased the colonic pressure

> activity compared with control and basal periods. Sham feeding

> and sight and smell of food without taste significantly (p < 0.02 and

> p < 0.03) increased colonic pressures compared with control but not

> basal activity. The increase in colonic activity after sight of food

> without smell or taste was not significantly different from control

> or basal activity (p = 0.44 and p = 0.34).

> Food discussion was the strongest colonic stimulus tested.(ABSTRACT

> TRUNCATED AT 250 WORDS) "

> The effect on stomach acid isn't described in the abstract (maybe

> it's in the truncated part) but as you can see they measured it to go

> along with their colonic measurements.

>

> I'm putting these examples in more to show that people are actually

> measuring these things than to make any point about the stomach.

> You would need to look at a number of references to see the different

> ways that research might be done on the stomach - I'm sure there are

> many approaches. Using radio-transmitting pH electrodes in capsules

> that can be swallowed or pH electrodes on wires that can be lowered

> into the stomach are two other ways of measuring acidity in the

> stomach.

> (One textbook I have does say that many of Beaumont's observations

> and conclusions remain unchanged today.)

>