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Documenting my experience
Quote from ggenereux on May 5, 2021, 6:31 amQuote from Kurtis on May 5, 2021, 12:06 amcarotenoids are pigments - they capture energy from sunlight to produce energy in plants
Hi @kurtis,
I know that for a lot of plants the carotenoid content is much higher in the leaves than it is in the root. But, some plants also have a very high carotenoid content in the root, for example such as carrots and sweet potatoes.
Do you have think the root is acting like a reservoir of carotenoids to keep supplying the leaves, or do you think it's a dual purpose molecule to both absorb sunlight and to fight off insects that live in the soil?
Thanks.
Those plants were selectively bred by stupid humans to be as orange as possible. The orange carrot was made that way because a Dutch king liked orange.
By the way, virtually all fruit and vegetables in the grocery store are hybridized and bred by humans to have certain characteristics, so the "why would nature make it like that" is not really the most meaningful way to reason about those fruits and vegetables. Wild carrots are white, purple, or yellow. Although it would be interesting to know exactly why exactly some wild carrots are yellow.
@lil-chick I wouldn't worry about having a little bit of alcohol or a cigarette, dietary carotenoids are probably way more harmful.
Quote from michele on May 5, 2021, 7:41 amQuote from ggenereux on May 5, 2021, 6:14 amI think we will know for sure. Both from myself and from the update Dino recently posted:
https://ggenereux.blog/discussion/topic/lab-tests-after-2-1-2-years-end-of-experiment/
where he shared that his serum retinol (via RBPs) is at: 0,04 umol/L we are getting some good evidence that there's no need for the RBPs. That's 26 times lower than the low end of the normal range. Three years ago I was similarly at 22 times lower.
I know you scoff at people who think that you are still surviving and thriving because the red meat you are consuming contains some VA. I happen to be one of those people. Bison consume grass. Grass contains VA. If you believe VA is a poison, why on earth would you consume an animal whose diet is made up almost entirely of a poison?! While I agree that there may not be as much VA in bison as there is in a sweet potato, perhaps you are getting all you need. As I suggested with protein, perhaps the amount of VA needed is wildly off.
Serum retinol is simply a measure of what is in your blood. NOT what is getting into your cells. In your 5-year update, your VA level was 0.1 μmol/l (I didn't see this data point in your 6-year update). So, you are not at zero. Yes, you are very very low. Perhaps the small amount of VA in the bison is being almost 100% utilized by your cells, which means that most of the VA in your body is NOT in your blood and therefore would not appear in your blood test. Your body is going to work really, really hard to keep you alive and functioning. If it has only a very limited supply of VA coming in and it is in fact necessary for the body (and not a poison), it's likely going to figure out a way to use as much of it as possible.
Personally, all this proves to me is that the % of VA the medical community says is required is incorrect. Not that VA is a poison and/or unnecessary. The billion dollar supplement industry has drilled in our heads that we need massive amounts of vitamins and minerals to be healthy. I personally believe this is untrue for all vitamins and minerals. It's all about how much your body can actually absorb and utilize, not the amount you consume.
The USDA database reports bison’s vitamin A concentration to be 0 IU / 100g.
I wasn’t able to get my vA serum level tested last year. I hope to get it done again this fall.
Thanks
The other thread about scurvy put together with this thread might bring an insight. We have thought about how scurvy and VA toxicity have an overlap and might even be the same thing. Well, what did sailors take for it? limes... a fruit. As a result of this convo, I bought myself a box of organic strawberries this week, 🙂
Hi, it's hard to find information on the role of carotenoids outside of photosynthesis but they do have roles in cell signalling & plant growth. I think fruits/vegetables are selectively bred to be as vibrant as possible so people buy them at markets. The root of carrots were originally white according to google so it doesn't make sense to look at them from an evolutionary perspective
Quote from michele on May 5, 2021, 7:41 amI know you scoff at people who think that you are still surviving and thriving because the red meat you are consuming contains some VA. I happen to be one of those people. Bison consume grass. Grass contains VA. If you believe VA is a poison, why on earth would you consume an animal whose diet is made up almost entirely of a poison?!...Personally, all this proves to me is that the % of VA the medical community says is required is incorrect. Not that VA is a poison and/or unnecessary. The billion dollar supplement industry has drilled in our heads that we need massive amounts of vitamins and minerals to be healthy. I personally believe this is untrue for all vitamins and minerals. It's all about how much your body can actually absorb and utilize, not the amount you consume.
...
I think that eating animals that eat grass (or their eggs/milk) is an amazing feat of "technology" because it has allowed us to live in eco systems which are mainly grass. I keep chickens and think of chickens as technology, LOL. They literally turn grass and bugs into food for me.
Have you ever studied the frutarians of Harvard ma, they are quite an interesting story (a stones throw from me) Louisa May Alcott's father began the colony. It's BEAUTIFUL there. However, it didn't go well. Perhaps too far north for frutarians. On the other hand, mixed farming was successful here.
I do agree that meat probably isn't VA free, but what is? I think we can only go lowish. VA is ubiquitous. It could be that some carotenes are less toxic than others. (shrugs) Price seemed to think that there was a health benefit to eating animal foods during spring and fall when the grass grows lushly. It could be that in those times there is lots of vitamin K to be had from that carotene-ladened grass.
I also agree with you, Michelle, that probably the RDA's were pulled out of thin air, and lead people to take more supplements than they should.
But that harmonizes with my idea that we might need to only swerve our lifestyles a bit to be healthy and that heroic efforts are probably not needed.
Edited to add another thought: Are we using other animal's livers to take away some of the VA? By passing food through them?
https://en.wikipedia.org/wiki/Fruitlands_(transcendental_center)
A reminder that carotenoids are not the same as pre-formed Vitamin A and we should not refer to both of them as Vitamin A.
Carotenoids are generated by plants and serve as an antioxidant against UV damage in the plants, which is why they are typically found in the above-ground structures of terrestrial plants. Carotenoids seem to have been mistakenly considered an antioxidant in humans and other animals because they turn on the NRF-2 pathway, which is an antioxidative pathway, but the reason NRF-2 is turned on is to counteract the detrimental effect of the carotenoids. The same goes for all the other "antioxidant" plant compounds that stimulate NRF-2 and glutathione production in humans in order to get those compounds out of the body. They are xenobiotics that do not play a role in human biochemistry.
However, many animals convert certain carotenoids to retinol, including humans, and retinol appears to serve similar purposes in animals as carotenoids do in plants. You could think of retinoids as the animal version of carotenoids, although it's not a perfect analogy. Why would animals make this conversion and then store the converted product unless the body had a use for it? Surely, better mechanisms would have evolved to prevent the absorption of retinol and other pre-formed Vitamin A if it was purely toxic, and we certainly wouldn't retain the ability to convert carotenoids to retinol if that were the case. Natural selection doesn't always result in the best designs, but it does cull poor designs extremely effectively, and if carrying around a bunch of Vitamin A in the liver and elsewhere in the body did not serve a purpose and was actually quite detrimental, we would expect animals not to be storing huge quantities of it.
I think @ggenereux2014 and Dino are showing how little of the retinoids are needed by modern "civilized" people to be functionally healthy, but I agree with @michele that unless the blood levels drop all the way to zero and you can be absolutely sure that none of your food contains either carotenoids or pre-formed Vitamin A, you will never be able to prove that Vitamin A is not used and needed by the body.
Regarding fruit, I'm surprised that nobody has pointed out that many fruits are poisonous to humans. Yes, they are a vehicle for seed dispersal by getting animals to move the seeds around, but the plants are only going to give away as much energy in the flesh of a fruit as is required to get an animal to consume and relocate the seed. Plants are also going to have mechanisms for preventing a given species of animal from eating too much of their fruit because, beyond a certain number of fruits consumed, the plant gains become marginal - an animal is only going to move a seed so far within its home range, and the plant doesn't gain anything more from, say, 100 of its seeds falling within that home range than 20 seeds due to limited resources and competition for those resources in that home range.
Therefore, fruit is very much intended to become toxic to animal consumers beyond a certain amount, which will be species specific. Natural selection in fruit-eating animals is always selecting for traits that enable more fruit consumption without becoming toxic, whereas natural selection in fruit-producing plants is always selecting for traits that prevent animals from taking advantage of the plant's energy handouts.
As I said before, in biology, things only make sense through the lens of evolution. If you're going to argue about any of this stuff, you had better have a decent understanding of evolutionary principles.
Quote from wavygravygadzooks on May 5, 2021, 11:52 amA reminder that carotenoids are not the same as pre-formed Vitamin A and we should not refer to both of them as Vitamin A.
Carotenoids are generated by plants and serve as an antioxidant against UV damage in the plants, which is why they are typically found in the above-ground structures of terrestrial plants. Carotenoids seem to have been mistakenly considered an antioxidant in humans and other animals because they turn on the NRF-2 pathway, which is an antioxidative pathway, but the reason NRF-2 is turned on is to counteract the detrimental effect of the carotenoids. The same goes for all the other "antioxidant" plant compounds that stimulate NRF-2 and glutathione production in humans in order to get those compounds out of the body. They are xenobiotics that do not play a role in human biochemistry.
However, many animals convert certain carotenoids to retinol, including humans, and retinol appears to serve similar purposes in animals as carotenoids do in plants. You could think of retinoids as the animal version of carotenoids, although it's not a perfect analogy. Why would animals make this conversion and then store the converted product unless the body had a use for it? Surely, better mechanisms would have evolved to prevent the absorption of retinol and other pre-formed Vitamin A if it was purely toxic, and we certainly wouldn't retain the ability to convert carotenoids to retinol if that were the case. Natural selection doesn't always result in the best designs, but it does cull poor designs extremely effectively, and if carrying around a bunch of Vitamin A in the liver and elsewhere in the body did not serve a purpose and was actually quite detrimental, we would expect animals not to be storing huge quantities of it.
I think @ggenereux2014 and Dino are showing how little of the retinoids are needed by modern "civilized" people to be functionally healthy, but I agree with @michele that unless the blood levels drop all the way to zero and you can be absolutely sure that none of your food contains either carotenoids or pre-formed Vitamin A, you will never be able to prove that Vitamin A is not used and needed by the body.
Regarding fruit, I'm surprised that nobody has pointed out that many fruits are poisonous to humans. Yes, they are a vehicle for seed dispersal by getting animals to move the seeds around, but the plants are only going to give away as much energy in the flesh of a fruit as is required to get an animal to consume and relocate the seed. Plants are also going to have mechanisms for preventing a given species of animal from eating too much of their fruit because, beyond a certain number of fruits consumed, the plant gains become marginal - an animal is only going to move a seed so far within its home range, and the plant doesn't gain anything more from, say, 100 of its seeds falling within that home range than 20 seeds due to limited resources and competition for those resources in that home range.
Therefore, fruit is very much intended to become toxic to animal consumers beyond a certain amount, which will be species specific. Natural selection in fruit-eating animals is always selecting for traits that enable more fruit consumption without becoming toxic, whereas natural selection in fruit-producing plants is always selecting for traits that prevent animals from taking advantage of the plant's energy handouts.
As I said before, in biology, things only make sense through the lens of evolution. If you're going to argue about any of this stuff, you had better have a decent understanding of evolutionary principles.
You could make just the same argument about carotenoids. How come human bodies can store huge amounts of carotenoids if we don't have any use for it? How come it can be stored to such a degree it changes our skin color? Carotenemia? Lycopenemia? Maybe it's just hard to get rid off, I don't think the fact that it's stored is a good argument for its necessity. We store mercury from mercury exposure too. We store PUFAs from PUFA exposure and so forth.
Maybe we do need a little VA, but if you get enough of it even when you're eating the foods that contain the absolute least of it, then that's proof that at the very least, we need so little of it that it's impossible to become deficient of it unless you're eating a laboratory prepared diet. Also, the conversion process from beta-carotene to retinal isn't very complicated. The body just cleaves beta-carotene in half and it renders 2 retinal.
Quote from wavygravygadzooks on May 5, 2021, 11:52 amA reminder that carotenoids are not the same as pre-formed Vitamin A and we should not refer to both of them as Vitamin A.
Carotenoids are generated by plants and serve as an antioxidant against UV damage in the plants, which is why they are typically found in the above-ground structures of terrestrial plants. Carotenoids seem to have been mistakenly considered an antioxidant in humans and other animals because they turn on the NRF-2 pathway, which is an antioxidative pathway, but the reason NRF-2 is turned on is to counteract the detrimental effect of the carotenoids. The same goes for all the other "antioxidant" plant compounds that stimulate NRF-2 and glutathione production in humans in order to get those compounds out of the body. They are xenobiotics that do not play a role in human biochemistry.
However, many animals convert certain carotenoids to retinol, including humans, and retinol appears to serve similar purposes in animals as carotenoids do in plants. You could think of retinoids as the animal version of carotenoids, although it's not a perfect analogy. Why would animals make this conversion and then store the converted product unless the body had a use for it? Surely, better mechanisms would have evolved to prevent the absorption of retinol and other pre-formed Vitamin A if it was purely toxic, and we certainly wouldn't retain the ability to convert carotenoids to retinol if that were the case. Natural selection doesn't always result in the best designs, but it does cull poor designs extremely effectively, and if carrying around a bunch of Vitamin A in the liver and elsewhere in the body did not serve a purpose and was actually quite detrimental, we would expect animals not to be storing huge quantities of it.
I don't mind calling the whole thing VA because all VA comes from carotenes. All VA begins in plants. There is no animal VA. There is only broken down carotenes. It's all one family of chemicals that comes from plants. (please feel free to disuade me tho!). What we call VA is just broken down carotenes.
I'd love to think that we store VA for a reason, however, the only use I've heard of so far, that hasn't been shot down on this site-- is a very small amount in the retina. Which leads me to believe we store it because it's hard to get rid of. We don't INTEND to keep it or use it, we are just very slow in the process of getting rid of it. ? (feel free to disuade me of this too).
Maybe this makes sense because in some way the eye is turning light into energy (like in a plant doing photosynthesis) to fire neurons.
I chuckled at your point about poisonous fruit! I suppose there must be an animal for each poison fruit. Goats love poison ivy... the seeds come up everywhere in the yard, so I expect birds eat poison ivy berries too.
@salt The storage site for toxins that can't be excreted fast enough tends to be the fatty tissues, which is where carotenoids and metals end up, whereas critical nutrients are often stored in the liver. Excess Vitamin A winds up in the fatty tissues, but the primary pool is in the liver where things like B vitamins also reside. The location of storage makes all the difference in our interpretation of why it's there.
I'm not sure what your point is about the conversion of beta carotene to retinol being uncomplicated. The simplicity of a chemical process does not mean it's good or bad in a given context, and it says nothing about the actual rate of conversion. Beta carotene is known to be cleaved asymmetrically at times, leading to compounds that are potentially even more problematic than beta carotene itself...so apparently simplicity doesn't guarantee proper cleavage.
Maybe that reply was directed at me? your point was that we have to be careful about calling vitamin A and carotene by two different names, and my point is they are not two different things. what we call vitamin A is really just two halves of a carotene. There is no such thing as "animal VA". There is only cleaved carotenes. Cleaved carotenes, beta carotene and all the other carotese are all retinoids. They all come from plants. (originally)