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Yael Grauer
10-12-2008, 02:05 PM
I heard some dude with a PhD blame child obesity on decreased dopamine and serotonin. And here I thought it was all about insulin. He said it was the other chemicals that caused insulin resistance. And here I thought obesity and insulin resistance was based on diet... Anyone ever heard anything like that?

George Mounce
10-12-2008, 03:32 PM
I found this:

Tryptophan is an amino acid found in beef, chicken, dairy products and turkey. It helps the body produce more serotonin, the neurotransmitter or brain chemical which makes us feel good.

Serotonin is released by eating carbohydrate foods, and once released, suppresses the desire for carbohydrates via the action of insulin. This is believed to be a survival mechanism which has evolved to protect people from consuming too many carbohydrates at the expense of essential protein.

However, it is thought that in some people, the carbohydrate-serotonin mechanism goes wrong, causing carbohydrate cravings.

It is easy to conclude that eating more foods rich in tryptophan might help stop carbohydrate cravings by producing more serotonin. However researchers have discovered that when you eat a protein-containing food, the protein is digested into its constituent amino acids and the tryptophan is blocked from entering the brain by the other five amino acids that compete with it. For this reason, eating lots of protein does not raise the levels of tryptophan or serotonin in the brain.

One way to enhance brain serotonin production might be to take tryptophan itself. However tryptophan is not sold legally in many countries any longer due to serious adverse effects caused by products containing it in the past.

From: http://www.lowcarbiseasy.com/stop_sugar_and_carbohydrate_cravings.htm

I'm currently looking into more on Medscape. Drugs that increase serotonin production are used to help fight obesity.

My guess is that its in relation to kids getting way too many carbs (mainly of the processed variety) and their bodies pouring out tons of serotonin and just not being able to keep up. Fix? Don't give kids crap to eat.

Yael Grauer
10-12-2008, 08:58 PM
My guess is that its in relation to kids getting way too many carbs (mainly of the processed variety) and their bodies pouring out tons of serotonin and just not being able to keep up. Fix? Don't give kids crap to eat.

That was my guess too, but I keep forgetting that I'm not supposed to heckle speakers who have way more scientific knowledge than I do esp. at their events. :o But when I looked I found a 2001 study that showed that there were less dopamine receptors in people who are obese but the correlation etc. is unknown.

http://the-mouse-trap.blogspot.com/2007/09/obesity-dopamine-connection.html

I bet Robb might know...

Mike ODonnell
10-12-2008, 09:28 PM
Many hormones go on at night...melatonin, serotinin, GH, cortisol, insulin.....lack of sleep means messed up hormones.....always the same old message....go to bed and you will be better off. If seratonin is low, cravings go up.....seratonin is converted into melatonin at night....all interconnected.

Yael Grauer
10-12-2008, 09:42 PM
Well Robb pointed out to me that seratonin and dopamine are neurotransmitters, not hormones.

http://www.washingtonpost.com/wp-dyn/content/article/2007/08/31/AR2007083101860.html?wpisrc=newsletter&wpisrc=newsletter&wpisrc=newsletter

Mike ODonnell
10-12-2008, 10:22 PM
Well Robb pointed out to me that seratonin and dopamine are neurotransmitters, not hormones.

Tomato...Tomatoe....Technically....so is Norepinephrine as well but many call that a hormone too. But that just defines the way in which it is secreted and distance travelled (travel across a synaptic cleft and have a more rapid effect). Both are still chemical messengers at heart.

No one knows when the obese people in the study lost their dopamine receptors in the brain or if that loss could be reversed with weight loss.
Same message....get sleep, stay away from sugar, eat fat esp Omega 3s for healthy brain function. Science looks for specific issues when the main issue could be the lifestyle compounded over time....not some genetic defect. But if the brain gets messed up for any reason....the body sure will reflect it.

Yael Grauer
10-13-2008, 07:18 AM
Well, there ARE reasons neurotransmitters could be affected over time that have nothing to do with diet or sleep.

But I am just trying to figure out if it's those or the hormones that are most responsible. Where are all the science geeks?

I wish I was smart enough to be a science geek.

George Mounce
10-13-2008, 07:48 AM
Well, there ARE reasons neurotransmitters could be affected over time that have nothing to do with diet or sleep.

But I am just trying to figure out if it's those or the hormones that are most responsible. Where are all the science geeks?

I wish I was smart enough to be a science geek.

Yael, good reads:

http://serendip.brynmawr.edu/bb/neuro/neuro99/web1/Byrd.html
http://www.ncbi.nlm.nih.gov/pubmed/8697046
http://www.ncbi.nlm.nih.gov/pubmed/6381575
http://www.ncbi.nlm.nih.gov/pubmed/3527063
http://www.ncbi.nlm.nih.gov/pubmed/3056265

Mike ODonnell
10-13-2008, 08:25 AM
Well, there ARE reasons neurotransmitters could be affected over time that have nothing to do with diet or sleep.

I am not that much of a geek to know the intricate details....but my "guess" would be diet still as a major contributor...namely a high insulin environment/insulin resistance by excessive sugar/processed carb intake and lack of EFAs like DHA would greatly impair proper brain function. That and any other chemicals that come to find a home in the brain like Mercury or whatever else is in the environment.

Dave Van Skike
10-13-2008, 09:32 AM
Well, there ARE reasons neurotransmitters could be affected over time that have nothing to do with diet or sleep.

But I am just trying to figure out if it's those or the hormones that are most responsible. Where are all the science geeks?

I wish I was smart enough to be a science geek.

I think you just asked one of the BIG questions. I wouldn't look for a definitive answer on this one for a while (ever).

I've tinkered with brain chemistry and this is an area where I split the difference with the naturopaths: control your diet, get fish oil and some moderate excercise outside, and talk therapies sorted first, then look at interventions.

SSRI's and Dopamine whoosey whatsits are super powerful drugs that really do help a lot of people, for amny many others, their serotonin problems get fixed by talk therapy alone. obviously, diet helps hugely as does excercise and sunlight. If the system is so easily altered, why use the nuclear option unless you have to?

Yael Grauer
10-15-2008, 12:52 AM
Oh, I didn't mean drugs!! I meant controlling one's environment, having better support networks, etc. Though I do think it's perfectly acceptable to tweak neurotransmitters on a temporary basis with things like 5HTP or tryptophan or GABA or whatnot. But B vitamins for me are just as effective.

I've got lots more to write on this but will have to put it off until the weekend... Stay tuned! :)

Steven Low
10-15-2008, 06:28 AM
Well, there ARE reasons neurotransmitters could be affected over time that have nothing to do with diet or sleep.

But I am just trying to figure out if it's those or the hormones that are most responsible. Where are all the science geeks?

I wish I was smart enough to be a science geek.
It's both. As MOD said.. everything is interconnected.. much as performance depends on input from exercise/workouts, diet and sleep so does the body's overall health from those 3 and other factors too (stress, etc.).

In any case, LIKE insulin I would speculate (having not googled this) that the reason why the pathway gets messed up is much like the downregulation of receptors. For instance, abnormally high insulin levels cause insulin receptors on cells to be removed eventually causing resistance at target tissue level or the other way which is the pancreatic B-cells just stop working b/c of too much insulin. In any case, downregulation does pretty much affect all receptors of the body.. so if too much serotonin is being produced, there would be a downregulation effect with less receptors or the axons that produce them to provide less of a response.

George's first link on SSRIs as antidepressents makes me pretty much sure of that hypothesis namely because inhibiting uptake of serotonin is basically like increased serotonin output (by allowing the serotonin to exist longer and bind to more receptors).

Emily Mattes
10-17-2008, 01:19 PM
Steven, if I am not mistaken the serotonin uptake problems you describe (serotonin/dopamine receptors being overloaded, and the body learning to uptake less as a result) are also used to explain addiction, correct?

This cycle is a physiological explanation for why food can be such a psychological comfort . . . It would be interesting to compare the brain scans of a very obese person eating a candy bar with a heroin addict receiving an injection of methadone (as I highly doubt any research facility would be allowed to use tarballs!).

Brian Lau
10-18-2008, 12:17 PM
This cycle is a physiological explanation for why food can be such a psychological comfort . . . It would be interesting to compare the brain scans of a very obese person eating a candy bar with a heroin addict receiving an injection of methadone (as I highly doubt any research facility would be allowed to use tarballs!).

Good idea Emily! Thought you might be interested in a paper published yesterday on this very topic (http://www.sciencemag.org/cgi/content/short/322/5900/449) (Stice et al., 2008; abstract below). It's been known for some time that obsese individuals have fewer dopamine receptors in a specific brain area (e.g., Wang et al. 2001 (http://www.ncbi.nlm.nih.gov/pubmed/11210998?dopt=Abstract)), which may be due to genentic predisposition or dopamine receptor downregulation. The paper by Stice et al. adds to this by showing that activity in this brain area in response to food (a chocolate milkshake) is blunted in overweight subjects, and is in fact negatively correlated with BMI across the subject pool (higher the BMI the more blunted the response).

Stice et al. (Science, Oct 17, 2008) abstract:
"The dorsal striatum plays a role in consummatory food reward, and striatal dopamine receptors are reduced in obese individuals, relative to lean individuals, which suggests that the striatum and dopaminergic signaling in the striatum may contribute to the development of obesity. Thus, we tested whether striatal activation in response to food intake is related to current and future increases in body mass and whether these relations are moderated by the presence of the A1 allele of the TaqIA restriction fragment length polymorphism, which is associated with dopamine D2 receptor (DRD2) gene binding in the striatum and compromised striatal dopamine signaling. Cross-sectional and prospective data from two functional magnetic resonance imaging studies support these hypotheses, which implies that individuals may overeat to compensate for a hypofunctioning dorsal striatum, particularly those with genetic polymorphisms thought to attenuate dopamine signaling in this region."

Yael Grauer
10-18-2008, 01:00 PM
Fascinating! Thanks, Brian.

Jared Buffie
10-18-2008, 04:27 PM
What I recall from Lights Out....

Seratonin is released with insulin. Seratonin is responisible for happy moods. This explains why we crave sweets when depressed/stressed.

Problem: with over consumption of carbs over time, insulin receptors burn out (downregulation), which leads to insulin resistance and eventually Type II diabetes. At the same time in the brain, seratonin receptors burn out, thus the brain is incapable of feeling happy (depression).

The way the MD treats diabetes is by giving drugs to either create more insulin to bombard the already burnt out receptors with (metformin) or have the body to create new fat cells to increace the number of receptosr (Glyboride).

The way the MD treats the downregulation of seratonin receptors in the brain is similar - he presribes SSRI's, which increaase the amount of seratonin circulating in the brain by binding to the sites in the synapse where the seratonin reenters the neuron after creating the action potential in the adjoining neuron. This will work for a while, but over time, the receptors will burn out alltogether. That's why when you meet someone who has been on SSRI's for an extended period, it's like their soul is missing - they have lost the capability to really "feel".

The problrem arises when other duties of seratonin become affected - seratonin is a neurotransmitter that plays a role in impulse control. So now you have a population of people who cannot feel joy and have no impulse control - thus the black box warnings for SSRI's and suicidality.

Anyway, there are tons of studies linking diabetes and depression.

Yael Grauer
10-18-2008, 10:51 PM
Thee are also other things at play, too. For example social relations change brain chemicals like dopamine, serotonin, opiates, etc. Dopamine may be triggered by eating but it is also triggered by succeeding at something. Being bullied or chronically teased reduces serotonin. Puberty depletes dopamine and serotonin. Lack of exercise reduces serotonin and dopamine, etc.

Dave Van Skike
10-19-2008, 05:43 AM
That's why when you meet someone who has been on SSRI's for an extended period, it's like their soul is missing - they have lost the capability to really "feel".
.....

...seratonin is a neurotransmitter that plays a role in impulse control. So now you have a population of people who cannot feel joy and have no impulse control - thus the black box warnings for SSRI's and suicidality.


That is a fairly strong assertion you have made there. I gotta tell ya, that comes off as alternately judgmental and totally insane.

Jared Buffie
10-19-2008, 08:27 AM
That is a fairly strong assertion you have made there. I gotta tell ya, that comes off as alternately judgmental and totally insane.

Um.....

Meant to be more matter of fact than judgemental. And based on the physiology and research, not insane at all.

Spend a few moments googling SSRI + suicide and diabetes + depression.

Normally when I have a response like that after talking about SSRI's, it's based more on the person's personal experience/philosophy than anything I've stated. Everything I said (with the exception of the "losing ability to feel thing - that is based on personal experience dealing with literally hundreds of people who have been very sick for a long period and on a least one antidepressant, but more ofter two or three over extended periods) you can find in any neurophysiology/endocrinology textbook.

And yes, there are WAY more things that effect hormones and neurotransmitters - almost everything does! For example, in almost every study done, exercise beats SSRI's for depression. I was just looking at one part of it with the diabetes link.

Sorry if I cam across judgemental/insane. The good news is that if I am indeed insane, there are plenty of drugs out there for me....

Dave Van Skike
10-19-2008, 09:54 AM
Sorry, I googled "missing soul" + study + SSRI and didn't get a fount of scientificals....

I understand what the med lit says, it's the spin that's judgey, your experience notwithstanding. I'm sure, as a Dr., you'll appreciate the baby/bathwater analogy. Certainly there are terrible sides and certain populations for whom SSRI's lead to terrible effects...then there's another set of populations for whom they are lifesavers.


JK about the google part...google is not researching, it's just changing the channel. and for the record, all my psychoactive drug use is self prescribed.

Yael Grauer
10-19-2008, 05:03 PM
I googled "missing soul" + study + SSRI and this is what I found:

http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=103x238742