Food cravings

Hi again. I read today that the reason you "must" get a fatty food item
when you walk past the food court in the mall is that, the moment you
smell food your body starts producing insulin because your body
"thinks" you're about to eat. Is there any evidence of this?

Ignoramus16317 wrote:
On 22 Apr 2005 19:03:10 -0700, Andrew wrote:

Hi again. I read today that the reason you "must" get a fatty food item
when you walk past the food court in the mall is that, the moment you
smell food your body starts producing insulin because your body
"thinks" you're about to eat. Is there any evidence of this?



Insulin is used for converting carbs into energy, not fat. So, I
cannot see how one would want fatty food items because of insulin.

I suspect that wanting food when walking past food court is because
food has attractive smell.


http://www.bnl.gov/bnlweb/pubaf/pr/2002/bnlpr052002.htm


New Food-Addiction Link Found
Mere sight/smell of food spikes levels of brain “pleasure” chemical

UPTON, NY — Scientists at the U.S. Department of Energy’s Brookhaven
National Laboratory have found that the mere display of food — where
food-deprived subjects are allowed to smell and taste their favorite
foods without actually eating them — causes a significant elevation in
brain dopamine, a neurotransmitter associated with feelings of pleasure
and reward. This activation of the brain’s dopamine motivation circuits
is distinct from the role the brain chemical plays when people actually
eat, and may be similar to what addicts experience when craving drugs.

“Eating is a highly reinforcing behavior, just like taking illicit
drugs,” said psychiatrist Nora Volkow, the study’s lead investigator.
“But this is the first time anyone has shown that the dopamine system
can be triggered by food when there is no pleasure associated with it
since the subjects don’t eat the food. This provides us with new clues
about the mechanisms that lead people to eat other than just for the
pleasure of eating, and in this respect may help us understand why some
people overeat.” The study will appear in the June 1, 2002 issue of
Synapse (now available online ).

Brookhaven scientists have done extensive research showing that
addictive drugs increase the levels of dopamine in the brain, and that
addicts have fewer dopamine receptors than non-addicts. Last year, in an
effort to understand the relationship of the dopamine system to obesity,
they found that obese individuals also had fewer dopamine receptors than
normal control subjects.

In the new study, the scientists investigated the role of dopamine in
food intake in healthy, non-obese individuals. The researchers used
positron emission tomography (PET), a brain-scanning technique, to
measure dopamine levels in 10 food-deprived volunteers. Each volunteer
was given an injection containing a radiotracer, a radioactive chemical
“tag” designed to bind to dopamine receptors in the brain. The PET
camera picks up the radioactive signal to measure the level of tracer.
Since the tracer competes with dopamine for binding to the receptor, the
amount of bound tracer can be used to infer the concentration of
dopamine (more bound tracer = less dopamine).

These brain scans can be used to infer brain dopamine levels in the four
experimental conditions (with and without food stimulation, paired with
and without an oral dose of Ritalin). Note that the tracer signal in the
Ritalin + food scan is significantly lower than the others. This is
because the radiotracer competes with natural brain dopamine for binding
to the receptor. When there is a lot of tracer bound (the first three
conditions), it means there is not as much natural brain dopamine. When
there is little tracer bound (as in the Ritalin + food scan), there is
more natural brain dopamine occupying the receptor sites. So, it is an
inverse relationship (a low tracer signal = a high dopamine level).
Hi-res image (300 dpi jpeg).

Study subjects’ brains were scanned four times over a two-day period,
with and without food stimulation, paired with and without an oral dose
of methylphenidate. Methylphenidate (Ritalin) is known to block the
reabsorption of dopamine into nerve cells. The researchers wanted to see
if it would amplify any subtle changes in dopamine levels.

For food stimulation, the volunteers were presented with foods they had
previously reported as their favorites. The food was warmed to enhance
the smell and the subjects were allowed to view and smell it, as well as
taste a small portion placed on their tongues with a cotton swab. As a
control, during scans when food stimulation was not used, subjects were
asked to describe in as much detail as possible their family genealogy.
Study participants were also instructed to describe, on a scale of 1 to
10, whether they felt hungry or desired food prior to food stimulation
and then at five-minute intervals for a total of 40 minutes.

The researchers found that food stimulation in combination with oral
methylphenidate produced a significant increase in extracellular
dopamine in the dorsal striatum. There was also a correlation between
the increase in dopamine triggered by food stimulation and
methylphenidate and the changes in self-reports of ‘hunger’ and ‘desire
for food.’ “This suggests the dopamine increases during the
food/methylphenidate condition reflect the responses to food stimulation
and not the isolated effects of methylphenidate,” Volkow said.

The study demonstrates that methylphenidate, when used at low doses,
amplifies weak dopamine signals. It also shows, for the first time, that
the dopamine system in the dorsal striatum plays a role in food
motivation in the human brain.

This relationship was not observed in the ventral striatum, which
includes the nucleus accumbens, the area of the brain thought to be
responsible for food reward. “We and others previously thought the
nucleus accumbens was the primary brain region associated with
regulating food intake by modulating reward and pleasure while eating,”
said study coauthor Gene-Jack Wang. “These findings challenge that belief.”

This study was funded by the U.S. Department of Energy, which supports
basic research in a variety of scientific fields, and the National
Institute on Drug Abuse.

Andrew wrote:
Hi again. I read today that the reason you "must" get a fatty food
item
when you walk past the food court in the mall is that, the moment you
smell food your body starts producing insulin because your body
"thinks" you're about to eat. Is there any evidence of this?

I don't generally get this feeling; I walk past the fast food court
pretty easily. I guess the only thing that makes me want to eat is the
smell of the pizza (the cheese, really). I think we just like the taste
of these things, and we associate the smell with the taste. I think
sometimes we forget that eating food is a very pleasurable experience,
no matter how much we want to think of food as only fuel.

I only get the feeling that I *must* have chocolate if I see it, and
it's during my PMS period. Which I have right now, which is causing me
to eat far too much chocolate than I should. So far tonight I've eaten
1 raspberry-cream truffle, 1 chocolate-dipped dried apricot, five of
those mini cadbury eggs, 1 small square of dark chocolate, and 2
newman-o chocolate sandwich cookies. I even tried to eat some cashews,
a no-sugar added energy bar and some baby carrots but nothing has
helped. I still want to eat chocolate. Excuse the irrelevance but I'm
starting to get ****ed that I'm so insatiable. I would go for a walk or
something but it's raining and cold.

I wonder if this has to do with my rushed breakfast this morning, or
the fact that I couldn't eat enough during the day and was so starving
before dinner I could have eaten just about anything. I had to eat one
of those Dannon Light 'n Fit yogurts and some vegan 'suncakes' on the
go when I usually eat something like eggs or oatmeal with protein
powder. Breakfast had enough protein but maybe too much sugar. Oh well.

"Stacey Bender" wrote in message
...
Ignoramus16317 wrote:
On 22 Apr 2005 19:03:10 -0700, Andrew wrote:

Hi again. I read today that the reason you "must" get a fatty food item
when you walk past the food court in the mall is that, the moment you
smell food your body starts producing insulin because your body
"thinks" you're about to eat. Is there any evidence of this?



Insulin is used for converting carbs into energy, not fat. So, I
cannot see how one would want fatty food items because of insulin.

I suspect that wanting food when walking past food court is because
food has attractive smell.


http://www.bnl.gov/bnlweb/pubaf/pr/2002/bnlpr052002.htm

Article snipped

That makes sense _ I've got a whole load of brazil nut butter toiletries
that smell just like chocolate caramel and they really do seem to have a
"feel good factor"!

Rachael
176/117/111

"Andrew" wrote in message
oups.com...
Hi again. I read today that the reason you "must" get a fatty food item
when you walk past the food court in the mall is that, the moment you
smell food your body starts producing insulin because your body
"thinks" you're about to eat. Is there any evidence of this?

I don't think it necessarily relates to fatty foods. With so many different
foods being served in those places, we're attracted to the smell of things
we like best and if you don't like certain foods you may be repulsed by that
smell. Your reaction can be very different according to the circumstances:
if you're hungry or have been avoiding those foods for a while you may feel
you can't resist, if you've just stuffed yourself elsewhere you may feel
like getting out of the place quickly.