Gut serotonin and metabolic rate

[Kasper]

Ray Peat has talked a lot about gut serotonin. He thinks that serotonin lowers the bodies metabolic rate. I know RRM thinks ray peat is a little bit nuts, but this new study talks about something very similar:

http://www.nature.com/nm/journal/vaop/n ... .3766.html

Also explained in this article:
http://www.medicaldaily.com/serotonin-o ... age-313460

[RRM]

This is basic pharma logic.
'Obesity is characterized by elevated peripheral serotonin, which we may target with drugs'.

What does Peat say?
Obesity is caused by elevated gut serotonin?

[Kasper]

I think Ray Peat says that gut serotonin lowers the metabolic rate. He also thinks that estrogen, and prolactin lower the metabolic rate if I recall correctly. I don't know if he writes much about obesity, but he think many diseases are prevented or cured by fixing a low metabolic rate.

[Aytundra]

Kasper,
What is metabolic rate?
What is "lower" metabolic rate?

[Aytundra]

I think Ray Peat says that gut serotonin lowers the metabolic rate.

I can't figure it out:
I think:
a. if someone has low metabolic rate, i seem to think they metabolize things slowly.
b. if someone has high metabolic rate, i seem to think they metabolize things quickly.
c. if someone has low metabolic rate, does that mean? obesity?
d. if someone has high metabolic rate, does that mean? skinniness?
e. if serotonin intake in the gut lowers the metabolic rate, how does that help obesity? (if we assume statement c. is true)

[Kasper]

I see it like this, say you burn 1500 calories a day. But you eat 2000 calories, then you will likely get fat. But if you increase your metabolic rate so that you burn 2000 calories, you won't get fat.

So therefore increasing your metabolic rate, could be helpful with maintaining a good weight. Someone could say, just eat 1500 calories a day, and you will be fine as well. Ray Peat would however argue that having a low metabolic rate is not healthy.

[Aytundra]

1500 burn + 2000 eat = fat
1500 burn + 1500 eat = no change

increase your metabolic rate:
1500 burn (base metabolic rate) + 1500 eat + X amount of burn more = 3 options dependant on what X is: 1. fat, 2. no change, 3. loss fat

i don't get how you can burn less (lower metabolic rate compared to your base rate.)?

[Kasper]

Well, your base rate can get lower if you for example produce less thyroid hormone for some reason. That is called hypothyroidism.

This article suggests that high gut serotonin can lower the amount of brown fat cells. And brown fat cells increase the basal metabolic rate, so gut serotonin therefore would lower the metabolic rate.

According to Ray Peat, fibers can irritate the gut, and this irritation leads to the release of serotonin. This would make sense in some way as, according to Wikipedia:

"If irritants are present in the food, the enterochromaffin cells release more serotonin to make the gut move faster, i.e., to cause diarrhea, so the gut is emptied of the noxious substance."

So eating little fibre would be a good strategy, Ray Peat also recommends eating small meals, as big meals can irritate the gut and therefore release serotonin.

Note that gut serotonin and brain serotonin have different roles and seem to be independent of each other. Or maybe their is an inverse correlation as autistic child's have low brain serotonin and high gut serotonin.

[Aytundra]

Well, your base rate can get lower ... high gut serotonin.

This is what I am reading:
2000 eat + (BMR = 1500 calories/day) = 1500 burned = 500 calories excess
1500 eat + (BMR = 1500 calories/day) = 1500 burned = 0 calorie excess
2000 eat + (BMR = 2000 calories/day) = 2000 burned = 0 calorie excess <--- This is what I think, you think Ray Peat wants desire-to-lose-weight-people to do, eat same calories, but increase BMR, as to have zero calories excess.

To increase BMR to 2000 calorie/day, there are 2 options: <--- This is what I think, you think on what Ray Peat & the article thinks.
a) eat less serotonin foods to decrease gut serotonin, to increase brown fat, to increase BMR, to burn calories.
b) eat less fiber to decrease gut serotonin, to increase brown fat, to increase BMR, to burn calories.
To keep 0 excess calories, you may add in options: <--- I think
c) exercise, to burn calories
d) eat less calories
e) eat more fiber and more serotonin foods so to have bowel movements more often, hence quicker evacuation of food stuff from the digestive track and less food is absorbed, to consume less calories...{ this silly option is based on:

According to Ray Peat, fibers can irritate the gut, and this irritation leads to the release of serotonin. This would make sense in some way as, according to Wikipedia:

"If irritants are present in the food, the enterochromaffin cells release more serotonin to make the gut move faster, i.e., to cause diarrhea, so the gut is emptied of the noxious substance."

}
My logic says: removing serotonin and eating serotonin will make you lose calories, so it does not matter what you do with serotonin.
Valid options left for manipulating weight is back to c) and d).

[dime]

Why is higher metabolic rate healthier? Other than because of the potential weight loss?
I think it is quite widely accepted that lower metabolic rate = longer life expectancy.

Changing the metabolic rate is not so easy anyway.. going on extreme caloric restriction lowers metabolic rate by only 10%. Doing weightlifting and building a lot of muscles also doesn't affect much BMR.

A decrease in food intake can lower the metabolic rate as the body tries to conserve energy. Researcher Gary Foster, Ph.D., estimates that a very low calorie diet of fewer than 800 calories a day would reduce the metabolic rate by more than 10 percent.[27]

Higher metabolic rate is associated with not the best conditions for us, like various illnesses, hyperthyroidism etc.

Antithyroid agents, drugs used to treat hyperthyroidism, such as propylthiouracil and methimazole, bring the metabolic rate down to normal and restore euthyroidism.
...
The metabolic rate may be elevated in stress, illness, and diabetes.

Lower metabolic rate because of some illness however is of course not good, but trying to bring it higher if you're otherwise healthy and normal doesn't sound too good either.

Serotonin lowers the energy expenditure of brown fat, which is pretty much non-existent in adult humans as far as I know (they have just found some around the neck and upper chest). So again removing this serotoning block on brown fat functioning will not make a huge change in BMR. But maybe it is important in the early development of babies, as they have a lot of brown fat.

Further, recent studies using Positron Emission Tomography scanning of adult humans have shown that it is still present in adults in the upper chest and neck. The remaining deposits become more visible (increasing tracer uptake, that is, more metabolically active) with cold exposure, and less visible if an adrenergic beta blocker is given before the scan. The recent study could lead to a new method of weight loss, since brown fat takes calories from normal fat and burns it. Scientists were able to stimulate brown fat growth in mice, but human trials have not yet begun.[6][7][8][9] However, recently published results from study of mouse models demonstrate that cold exposure promotes atherosclerotic plaque growth and instability from activation of brown fat.[10]

[Kasper]

Serotonin lowers the energy expenditure of brown fat, which is pretty much non-existent in adult humans as far as I know (they have just found some around the neck and upper chest). So again removing this serotoning block on brown fat functioning will not make a huge change in BMR. But maybe it is important in the early development of babies, as they have a lot of brown fat.

This article does say that there is significant change in BMR. That brown fat cells are non-existent in adults is indeed a myth. The iceman is able to warm himself up by activating brown fat cells:
http://www.maastrichtuniversity.nl/web/ ... thing1.htm

If the icemand and his brother are able to warm them self up using brown fat cells, then I don't think you can say that brown fat activation can not mean a huge chance in BMR.

About if a fast metabolic rate is healthy or not, I don't understand most of the details of Ray Peat articles. I'm not sure if he advocates an extremely high metabolism or anything, he mostly warns for the dangers of a low metabolism.

For me, I've always had an extremely low heart rate. When I was tested 8 years ago, my heart fluctated between 29 and 45 bpm throughout the day. They always told me that it was a sign of health etc. sport heart blabla. But I didn't feel healthy at all. Maybe you age slower with a low heart rate and a low metabolism, but I think you also think slower, feel less alive and look less alive (especially my eyes).

Anyway, tried different things, throughout the years, and if my measure my heart rate, (sitting, non-stressed), and it is faster than the clock, than I feel good. When my hearts ticks slower than the clock, then I don't feel good. This better reflects how I feel than measuring my CP.

[RRM]

If the icemand and his brother are able to warm them self up using brown fat cells, then I don't think you can say that brown fat activation can not mean a huge chance in BMR.

Hmm.
Isn't that ulization of brown fat cells in response to exposure to low temperatures?
When it is cold, you need more energy to keep yourself warm.
BMR is not necessarily related, i think.

Anyway, tried different things, throughout the years, and if my measure my heart rate, (sitting, non-stressed), and it is faster than the clock, than I feel good. When my hearts ticks slower than the clock, then I don't feel good. This better reflects how I feel than measuring my CP.

How you feel may not reflect how good it is for you.
A lack of energy induces autophagy. Having plenty of energy available makes you feel better. Yet, autophagy extends lifespan.
What you feel, may actually be very good for you. Maybe you should count your blessings...

maybe it is important in the early development of babies, as they have a lot of brown fat.

Babies are very vulnerable to coldness. The brown fat serves as a protective buffer.

[Kasper]

How you feel may not reflect how good it is for you.
A lack of energy induces autophagy. Having plenty of energy available makes you feel better. Yet, autophagy extends lifespan.
What you feel, may actually be very good for you. Maybe you should count your blessings...

It is not only how I feel, but also how I look. Especially my eyes, I believe that eyes do reflect health in some way. I noticed that your childs have beautiful eyes. When my heart beats very slow, my eyes look more red, the skin under the eyes is more dark. I don't think this indicates good health.

I don't understand what you say about autophagy in this relationship, do you think that low metabolic rate or hypothyrodism could induce autophagy earlier ? I would think the more energy you use, the quicker you have a lack of energy (if you stop eating) and the quicker you induce autophagy.

[RRM]

When my heart beats very slow, my eyes look more red, the skin under the eyes is more dark. I don't think this indicates good health.

Sometimes our observations are tainted by how we feel.
Maybe you feel bad, and then you see something that reflects how you feel.
Im not saying that your observations are incorrect. Not at all. But maybe you can take a picture of how your eyes look when your heart beats slowly,
and then another picture of your eyes when you feel good. Then see for yourself, objectively, if you can see a difference.

I don't understand what you say about autophagy in this relationship, do you think that low metabolic rate or hypothyrodism could induce autophagy earlier ?

If your food is digested slowly, and taken up slowly, and utilized by your cells slowly,
there may be a relative lack of energy in the meantime, which may induce autophagy.
Or maybe not.
But my example was just meant to illustrate that how you feel does not necessarily reflect health.
When autophagy is induced, there is a relative lack of energy, which will make you not feel energetic.

I would think the more energy you use, the quicker you have a lack of energy (if you stop eating) and the quicker you induce autophagy.

A high metabolism is correlated with accelerated ageing; the more energy is used per unit, the faster that unit will age.
The less energy utilized per unit, the more ageing is inhibited.
So, the slower your metabolism, the longer you may live, potentially.
The result of autophagy is that you need less energy from the food that you eat, similar to a slower metabolism.