Fasting Inhibits Proper Thyroid Function

[Dhair]

I'm not sure if this has been posted before, but I thought it was interesting in light of our recent discussions about fasting.
Fasting-induced changes in the hypothalamus-pituitary-thyroid axis. - PubMed - NCBI
. "The observed decrease in serum thyroid hormone concentrations results to some extent from diminished thyroidal secretion of thyroid hormones, especially in rodents. Decreased thyroxine (T4) and T3 contribute to the downregulation of T3-responsive genes such as liver D1. The overall result of these complex HPT axis changes in various tissues during fasting is downregulation of the HPT axis, which is assumed to represent an energy-saving mechanism, instrumental in times of food shortage."

 

[Westside PUFAs]

That's not fasting. That's calorie restriction.

They say "The alterations observed in humans and rodents are similar in many ways, although they may be more pronounced and more acute in rodents."

Rodent calorie restriction is not the same as human, water-only.

The true definition of fasting for humans who would be reading this and not aliens or rodents is the complete abstinence from all substances except pure water, in an environment of complete rest, anywhere from 5 to 40 days. It's called clinical fasting or therapeutic fasting.



"In a fasted state, increased autophagy (breakdown and recycling of damaged and non-essential tissue) provides a source of amino acids, fatty acids, and minerals, and the energy previously used for digestion may be directed towards cellular regeneration.

The physiological adaptations that occur in the fasted state may produce various health improvements. Clinical evidence in humans suggests that fasting may improve hypertension, rheumatoid arthritis, cardiovascular disease, metabolic syndrome, osteoarthritis, fibromyalgia, chronic pain, chemotherapy side effects, and quality of life.

Despite the possible good outcomes, water-only fasting is also not a cure or treatment in the traditional sense; it is simply intended to promote the body’s self-healing mechanisms. In order to maintain the results obtained by water-only fasting, it is necessary to adhere to a health-promoting lifestyle that includes a healthy diet, adequate sleep, and proper exercise."

 

[Westside PUFAs]

I sent Ray Peat a study on human, water-only fasting once and his response was "Thanks. That’s reminiscent of Johanna Brandt’s grape cure and Max Gerson’s program. Fasting has often eliminated all symptoms of rheumatoid arthritis. I think intestinal toxins (indole breakdown products, etc.) are big factors in cancer."

I don't think it's something he would recommend but he seemed to think it was okay for rheumatoid arthritis.

All other Peat comments on fasting are on calorie restriction and not the definition above.

 

[Dhair]

I sent Ray Peat a study on human, water-only fasting once and his response was "Thanks. That’s reminiscent of Johanna Brandt’s grape cure and Max Gerson’s program. Fasting has often eliminated all symptoms of rheumatoid arthritis. I think intestinal toxins (indole breakdown products, etc.) are big factors in cancer."

I don't think it's something he would recommend but he seemed to think it was okay for rheumatoid arthritis.

All other Peat comments on fasting are on calorie restriction and not the definition above.

Thanks for responding to this.
I'm surprised that Ray was aware of those effects.
Have you found any connection between fasting and nitric oxide ?

 

[TubZy]

That's not fasting. That's calorie restriction.

They say "The alterations observed in humans and rodents are similar in many ways, although they may be more pronounced and more acute in rodents."

Rodent calorie restriction is not the same as human, water-only.

The true definition of fasting for humans who would be reading this and not aliens or rodents is the complete abstinence from all substances except pure water, in an environment of complete rest, anywhere from 5 to 40 days. It's called clinical fasting or therapeutic fasting.



"In a fasted state, increased autophagy (breakdown and recycling of damaged and non-essential tissue) provides a source of amino acids, fatty acids, and minerals, and the energy previously used for digestion may be directed towards cellular regeneration.

The physiological adaptations that occur in the fasted state may produce various health improvements. Clinical evidence in humans suggests that fasting may improve hypertension, rheumatoid arthritis, cardiovascular disease, metabolic syndrome, osteoarthritis, fibromyalgia, chronic pain, chemotherapy side effects, and quality of life.

Despite the possible good outcomes, water-only fasting is also not a cure or treatment in the traditional sense; it is simply intended to promote the body’s self-healing mechanisms. In order to maintain the results obtained by water-only fasting, it is necessary to adhere to a health-promoting lifestyle that includes a healthy diet, adequate sleep, and proper exercise."

Yup, he keeps confusing a low carb diet versus pure fasting.

 

[Diokine]

I think that continued thyroid output during extreme stress could ultimately be fatal, so I would consider a drop in hormone levels to be proper functioning during a situation like that.

 

[Dhair]

Yup, he keeps confusing a low carb diet versus pure fasting.

The word "fasting" is literally in the title of the study. But I know what you are referring to, and I do know the difference. As we discussed before, there is hardly any verifiable research available concerning water-only long term fasting.

I think that continued thyroid output during extreme stress could ultimately be fatal, so I would consider a drop in hormone levels to be proper functioning during a situation like that.

Are you talking about a possible adrenergic crisis situation?

 

[Diokine]

Are you talking about a possible adrenergic crisis situation?

essentially

Thyroid hormone works in concert with the sympathetic nervous system to generate a driving force or "pressor" action upon metabolism. It does this primarily through altering the way the body handles calcium. So in a situation where there is a reduction of food, there will usually also be a drop in calcium. The sympathetic nervous system actually tends to increase activity during fasting, generally explained by an increase in catecholamine levels and increase in "receptor sensitivity." I like to think that the body is encouraging you to find and eat food.

But this increased pressing action from fasting requires a constant flux of ionized calcium, roughly speaking, to maintain the proper electrical gradients driving the continued rhythm of the cell. So here thyroid hormone levels must drop, or there could be a situation where the electrical reductive state of the cell is so great that it could not maintain life. Of course there are also factors like estrogen, cortisol, etc., helping to maintain this balance. Parathyroid is critical in this regard, as it generally encourages calcium liberation from bones and works to maintain serum ionization levels without the action of thyroid hormone, in concert with prostaglandins and estrogen.

-Parathyroid hormone and ionized calcium levels are related to the severity of illness and survival in critically ill patients.
Hypocalcaemia and increased levels of PTH were common findings in critically ill patients. These alterations in calcium homeostasis were related to the severity of disease and increased PTH levels were associated with a poor outcome.
​

So in this study, they looked at the levels of parathyroid and ionized calcium levels in people who rated to be very sick based on a metric used in intensive care settings called APACHE II. They found a very strong correlation between both of these markers and severity of illness. Parathyroid hormone increases in an attempt to maintain serum calcium levels, and if they can't be maintained - you die.


Starvation induces parathyroid hormone, as does nearly any other stress.

-The effects of fasting and refeeding on serum parathormone and calcitonin concentrations in young and old male rats.

-Effect of fasting and parathyroid hormone injection on plasma 45Ca concentrations in rats.
These data are consistent with the concept of a bone fluid compartment (BFC) separated by a cellular interface from the primary extracellular fluid space (ecf). It is postulated that through this cellular interface calcium is actively "pumped" from the BFC to the ECF. The rise in plasma 45Ca values at the start of fasting is explained on the basis of decreased entry of stable calcium from the gastrointestinal tract and a continued movement of calcium and 45Ca from the BFC to the ECF.



​

The second study talks about some interesting things, specifically the idea of a compartment of fluid around bone that almost acts as a membrane, selectively permitting or restricting the movement of some ionic compounds. Pretty cool to think about a "membrane" existing around these bones, controlling the flow of bone juice, kind of like the "membrane" around cells, controlling the flow of cell juice. So looking at the actions of estrogen, parathyroid hormone, calcitonin, etc., we can get an idea of how these compounds control the permeability of these "membranes."

-Bone Lining Cells and the Bone Fluid Compartment, an Ultrastructural Study






​

 

[alywest]

Wow, that's fascinating stuff @Diokine

Just thought I'd share this little gem from an interview with RP, too:

Q: Great show. I got a couple of questions that I wanted to sort of ask. What is your feeling on things like a liver flush and general cleansing that is sort of popular now in certain circles?

Dr. Ray Peat: There were experiments on cattle that were being sent in for slaughter. They measured their blood and urine and found that, I think it was 30 to 35% of them showed chemical toxins that they have been exposed to either in their feed or insecticides sprayed on them and such. But when they were slaughtered, they found that that same proportion 30, 35% had muscle and fat evidence of those same poisons but only 6 or 7% of them had any of those toxins in their liver. The liver has the equipment for gradually excreting the toxins that are stored in the fat and muscles. And so the liver is the cleanest organ of the animal. And if you slow down the liver’s activity which happens in a fast for example, then your brain and other organs are going to be exposed to the chemicals that otherwise would have been excreted in the urine as they are defusing out of your fat and muscles. So I think the best cleansing diet is one that increases your liver’s action and just tasty food is one of the things that will stimulate your liver’s action, or sugar and thyroid are the other main things that activate the liver.

East West: Questions & Answers I

 

[paymanz]

best cleansing diet is one that increases your liver’s action and just tasty food is one of the things that will stimulate your liver’s action,

Tasty food! Very interesting ,thanks.

 

[paymanz]

In a fasted state, increased autophagy (breakdown and recycling of damaged and non-essential tissue

I would like to know about tnose non essential tissues!

 

[paymanz]

I wondering why dont these fasting advocators doesnt add some mineral supplements during fast.

Especially salt,and maybe calcium.

And also even vitamins. Some of these vitaminfs has a half life of just few days.

 

[michael94]

I would like to know about tnose non essential tissues!

Not what most people think of when it comes to unimportant tissue... but most muscle people put on when "trying to put on muscle" is stress based waste. Especially if it is disproportionate to one's "blueprint." A lot of the fitness world is concerned with muscle sparing which is a good or bad thing depending on the conditions under which the muscle was gained.

 

[cyclops]

Not what most people think of when it comes to unimportant tissue... but most muscle people put on when "trying to put on muscle" is stress based waste.

Do you mean most of the "weight" people put on when trying to gain muscle is stress based waste, as in they get too fat and stuff? I dont think people are putting on toxic muscle?

 

[Jsaute21]

Studies are extremely useful but so is observational evidence. The healthiest people i know do not fast. I find it to be an orthorexic habit that is counter intuitive to life. I'm sure it works for some people, as the saying goes "some are built for feast, others for famine." However, for me, as a somewhat muscular and androgenic guy, it did absolutely nothing for me. Other people that do not fast: The worlds best pro athletes, world leaders, and intellects worldwide. Food is meant to be enjoyed, not manipulated to the point where you are starving yourself for hours on end. If you live an active life, i frankly don't understand how you fast and feel good throughout the day.

 

[paymanz]

Not what most people think of when it comes to unimportant tissue... but most muscle people put on when "trying to put on muscle" is stress based waste. Especially if it is disproportionate to one's "blueprint." A lot of the fitness world is concerned with muscle sparing which is a good or bad thing depending on the conditions under which the muscle was gained.

Yes i agree, maybe that is one of reasons why some smaller athletes have better performance,even in weight lifting.

 

[paymanz]

Ray also has mentioned autophagy is some articles, but havent speaked about it that much.

 

[paymanz]

If you live an active life, i frankly don't understand how you fast and feel good throughout the day.

 

[dbh25]

The healthiest people i know do not fast.

Lol

 

[Jsaute21]

Lol

Lol i realize that sounds silly, but it is true. I know a lot of successful people, and none of them fast. When i fasted, it affected my digestion and androgenic qualities immensely.