WHY Do PUFAs Inhibit Thyroid?

[nigma]

Ray Peat has lots of great information about life, health and the environment, but a lot of the time I am still left wondering... but why? Ray Peat has a lot of how questions answered for me but the whys keep bugging me.

The below is an attempt to explain some of the whys. I have looked around to see if anybody else is thinking the same but I did not find anything. Please let me know if this has already been put together by someone else.

This started because Ray said one must be careful of taking too much vitamin A because it can inhibit thyroid because of it is unsaturated... this got me thinking.. its not something unique to PUFA that inhibits thyroid, it is unsaturations, that is C=C, carbon carbon double bonds!

Hypothesis:
Why are PUFAs associated with obesity? Cause physics!
Also, why do PUFAs inhibit thyroid?

Plants produce different types of fatty acids dependent on their environment. Unsaturated fats have lower melting points directly proportional to their degree of unsaturation, this is due to weaker intermolecular forces / gravity. A lower melting point is necessary as the plant fat would not be flexible enough if it could only synthesise saturated fatty acids. In the natural world the degree of unsaturation is linked to the immediate environment. Saturated fats are tropical fats and appear/exist at the equator. The closer to the poles the higher the degree of unsaturation in fats. A salmon taken from the amazon river and dropped in an arctic level cold water bath would turn solid and likely die.

Unsaturated fatty acids are synthesised by life which exists at cold temperatures, including plants, fish and mammals (e.g. moose feet in snow would need to be made up of unsaturated fats). When consumed by a mammal PUFAs are one of the signals about the environment. PUFAs signal that life is hard and that energy needs to be conserved as it is unlikely to be abundant in the current environment. It also signals that carbohydrates are not available because the cold temperatures and lack of sunlight at the poles are not supportive of photosynthesis and starch production. Reducing the metabolism (torpor) is a way to conserve energy by limiting the amount spent and the amount lost to the environment (since the difference between body temp and ambient is reduced). This explains the thyroid inhibition of the PUFAs, i.e. it is functional and supposed to happen!!! Life would not survive without it (in certain contexts... like the cold).


Implications:
-The Ray Peat diet that supports thyroid is trying to recreate the conditions on the equator, a high energy environment that comes with high calories, high carbohydrates, saturated fats rather than PUFAs, lots of light and warmth (warmth is still light but you know... language).

What is this called?...... I suggest: eating to your latitude. or living to your latitude

-Not eating to your latitude needs to be avoided. One must keep the environmental signals to their body consistent. PUFAs and fruit do not appear in the wild together, so they should not be in the same diet.... or must only be eaten at different parts of the year. One should not eat many carbs unless their body is also getting the signal that light is plentiful, which is not easy since we all wear a substantial amount of clothing, etc.

-If someone craves PUFAs (they taste really good to them), their body is probably getting environmental signals that it is not in the tropics and that it would be good to reduce metabolism (by eating PUFA). This maybe because in the past few months they have been under eating calories, been in cold air conditioned environments, their skin/eyes didn't see a lot of light, were eating PUFAs, etc. (http://www.swarthmore.edu/Documents/biology/Hiebert_etal_CJZ_00.pdf)

-People get fat because of not eating/living to their latitude, the body is not able to correctly manage energy in and energy out.

-Obese people seem to be able eat an unlimited calorie high carbohydrate diet (McDougall style) and lose fat weight or eat an unlimited calorie high fat diet (Atkins) and lose fat weight. Both of these correct aspects of eating according to your latitude.

 

[paymanz]

The Influence Of Free Fatty Acids On The Free Fraction Of Thyroid Hormones In Serum As Estimated By

Carnitine inhibits thyroid function and pufas stimulate carnitin production more than mufas and SFA.
https://raypeatforum.com/community/threads/l-carnitine-is-anti-thyroid.3638/
Also in ray's view pufas disturbe energy production of cell,in general.it destabilize them,makes them to absorb more water,etc.
________

Your core temp is regardless of environment temp,so latitude doesn't make any difference I believe.we wearing warm cloths so...!

 

[Peater]

It's a fascinating theory as to the "Whys" of eat seasonal and local

 

[Richiebogie]

Unsaturated fatty acids are synthesised by life which exists at cold temperatures, including plants, fish and mammals (e.g. moose feet in snow would need to be made up of unsaturated fats).

Mammals are warm blooded unlike plants and fish, so all the fat they store can be saturated.

Ray Peat says that most PUFA foods are things our species never ate before. On the other hand Hibernating mammals may have evolved to live on salmon and nuts leading up to their hibernation.

Humans now have the technology to lead tropical lifestyles which will give us more health & vitality, so let's do that.

 

[XPlus]

You made some good assumptions although I wouldn't agree with you all the way.

Along the lines of your hypothesis I think there should be a question of what is ideal to a human.
My understanding is that we humans have the ability to adapt to different environments but not all environments offer ideal living conditions. In a not so ideal case, adaptability will be at a cost, like accelerated aging and disease.

PUFAs exist in fruit but this isn't the problem in nature I presume. Naturally they seem like a small part of edible items like demonstrated by traditional diets (e.g. he Okinawans didn't eat a California roll laced in mayonnaise) but the development of technology have introduced more of them into our food.

If someone craves PUFAs it could be the need for something associated with them like fat soluble vitamins, salt, sugar and trace minerals.

Also, I don't think people lose fat primarily on a diet like Atkins's. Much of the weight lost is muscle mass in my experience.

Finally, to answer your question of why PUFAs inhibit thyroid, it think its activation of the stress cycle mainly through estrogen.

 

[lvysaur]

If someone craves PUFAs it could be the need for something associated with them like fat soluble vitamins, salt, sugar

You could also say that people crave what they perceive to be rare.

For example, someone in a tropical state might crave PUFA, and a cold-state person might crave sugar, simply because those substances are so rare in those respective environments.

 

[XPlus]

You could also say that people crave what they perceive to be rare.

For example, someone in a tropical state might crave PUFA, and a cold-state person might crave sugar, simply because those substances are so rare in those respective environments.

I never crave gold or diamonds

 

[JohnA]

I agree with most of the OP's argument (until you argued that people at higher latitudes should eat more PUFAs). More than most other mammals, humans have evolved to thrive in the tropics (at the expense of living in colder latitudes). Thus, we should try to emulate tropical diet, light, and temperature patterns regardless of where you live. I think the hypometabolic symptoms that led many of us to RP are caused in part by the body entering a mild torpor/hibernation due to a lack of calories, sun, heat, or traumatic stress.

But I don't buy the argument that humans crave PUFAs in the same way that bears and squirrels eat nuts to enter hibernation. I think it's just that we crave highly palatable, high-calorie, high-fat foods. Unfortunately, most of these foods are now made with PUFAs instead of saturated fats. That's because vegetable oils are cheaper and we've been told how much healthier PUFAs are than saturated fats. But few people instinctively prefer margarine over butter or fries cooked in canola oil over fries cooked in coconut oil.

To answer the title question on why PUFAs are bad, see below one of my favorite articles from Ray on the topic: Ray Peat

 

[nigma]

Just to clarify. I didn't mean to imply that PUFAs should be eaten. I think they should be avoided as much as possible. However they would help organisms survive harsh environments, by sacrificing life span for survival.

 

[JohnA]

OK. I was confused by your last point about obese people being able to lose fat on an Atkins diet because they're eating correctly "according to their latitude".

Anyway, we're on the same page. To rephrase your argument, when omnivorous animals live at high latitudes in the winter, their diets become PUFA dominant because there's no fruit and the nuts and prey animals have high unsaturated fat levels so that they don't freeze. As you said, these PUFAs inhibit thyroid and encourage hibernation to reduce energy expenditure - a good outcome for squirrels and bears since it solves the winter paradox: endotherms need more calories in the wintertime to produce heat, yet there are less available food sources.

This is a terrible outcome for humans though, since we want to be active all year round and not suffer from torpor symptoms such as reduced body temperature, low energy, low sex drive, bad blood profiles, etc., each winter.

As Ray mentioned, eskimos avoid going into torpor because the PUFAs in their fish diet are countered by pro-thyroid nutrients from the fish's brain and thyroid gland.

 

[Giraffe]

Just to clarify. I didn't mean to imply that PUFAs should be eaten. I think they should be avoided as much as possible. However they would help organisms survive harsh environments, by sacrificing life span for survival.

We can make our own PUFA (Mead acid).

Aspirin, brain, and cancer

If we didn't eat linoleic acid and the other so-called "essential fatty acids," we would produce large amounts of the "Mead acid," n-9 eicosatrienoic acid, and its derivatives. This acid in itself is antiinflammatory, and its derivatives have a variety of antistress actions.