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Anthropology, appropriate diets, and Vitamin A questions
I stated something very similar to Luke in the discussion on the Hadza: https://ggenereux.blog/discussion/topic/hadza-hunter-gatherers/
Im still not convinced it's entirely toxic...and I often wonder about people reacting to the combination of copper and vitamin A, or something like that. Beef liver is high in copper and so are sweet potatoes, plus sweet potatoes are high in oxalates. When your liver is compromised you don't metabolize vitamin A properly. When your gut is compromised you don't metabolize cartenoids properly. And I think that the truth is always somewhere in the middle....too much vitamin A is not going to be good, but too little is going to effect the immune system/hormone production, testosterone is highly dependant on zinc and vitamin A. I mean, there are studies of rats becoming vitamin A deficient and having tons of problems...so there is also that...studies showing adverse effects with a deficiency.
Also, fully agree all supplements are toxic. And some people don't even realize that salt is a supplement...it's a mineral extract...it's not natural and causes high blood pressure/insulin resistance, throws off the balance of sodium-to-potassium ratio in the body. Just like dairy throws off the calcium-to-magnesium ratio of the cells. Humans are naturally supposed to have a blood pressure of around 100/60 and you can look at the Yanomami Indians for confirmation of that. Humans don't have access to salt in the wild, no modern day hunter gatherers naturally have access to it. I think you can look to nature in terms of diet. If I want to know what a tiger eats, it would be useful to observe it's eating patterns in a natural environment... that's just logical.
Hi Luke!
You don't even have to care about vitamin A to stop eating liver. If you don't like eating DDT which is a generally banned persistent organic pesticide (POP) then don't eat any liver (see page 120 in the mentioned report below). All the tested bovine liver samples contained DDT (10 out of 10) in "The 2010 European Union Report on Pesticide Residues in Food".
https://www.efsa.europa.eu/en/efsajournal/pub/3130
Another persistent organic pesticide, HCH, which the same report said was most commonly found in milk products and eggs, though I didn't see a percentage figure as with bovine liver.
Then there is all the pesticides that are still in use and out of all the tested foods in this 2010 report, 95.7% or 22 of 23 liver samples (bovine, sheep, goat, swine, poultry) contained at least two or more pesticide residues (see page 111).
Liver was the worst of any food that they test but they don't test all foods, they choose certain food categories each time but still livers tested worse than all the well-known highly sprayed foods such as citrus fruits, grapes of all kinds and strawberries.
My question to you, Luke:
How many times have you gotten and read a lab test of pesticide residue and Persistent Organic Pesticides (POPs) when you bought any form of liver?
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I am the first but hopefully not the last to call total bullshit on your comment. Have you even heard of Grant Genereux and read any of his free e-books? Do you even know that you are posting on his forum? Have you even thought of falsifying the experiment which is Grant Genereux? He has been living 7 years on a low vitamin A diet and he seems to be in really good health.
You mention vitamin A is necessary and important for testosterone production and says that there is rat studies showing that effect. You should post those studies with your comment since then others can see them and comment on them. Personally I believe most animals studies are at least in some way inherently faulty if only because most of the time the animals are feed extremely processed foods.
Please in the future bring some substance to the discussion instead of just your highly trollish generalizations!
Grant Genereux did an experiment with rats, mice, etc. He put them on a true zero vitamin A diet. They lived a long time, long after people said the effects of no vitamin A should have killed them. Grant posted videos of these rodents. They had no testosterone problems. They were the most healthy, active, glossy coated rodents I've seen. They were superior specimens.
@david For the record not discouraging anyone for doing a low vitamin A diet.
If you think I'm trolling that's fine...you can look at my profile, I've been a member on this forum for years now(longer than you David)...
1) "Vitamin A and iron supplementation is as efficient as hormonal therapy in constitutionally delayed children
conclusions Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty."
Source: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2265.2004.02034.x
2) "Testosterone glucuronide exhibited significant correlations with calories and vitamin A. This study suggests that dietary intake affects plasma sex-steroid levels in men."
Source: https://pubmed.ncbi.nlm.nih.gov/3360302/
3) "In this rodent study, it was noted that the testicular system of rats contains several receptor sites for vitamin A and that it can be stored in testicular Sertoli cells. What’s more interesting is that when the rodents diets were cut off from all vitamin A, testosterone production rapidly decreased (up to the point of where sexual organs literally atrophied), and estrogen exposure inside the testes rose rapidly (as humans share nearly identical testicular systems with Wistar rats, this becomes very interesting)."
Source: hyperlinked "rodent study"
4) "The decrease in the binding characteristics of PBRs in testes due to vitamin A deficiency was accompanied with a corresponding decrease in the levels of testosterone in plasma. These results suggest a close functional relationship of vitamin A with PBRs in testes."
Source: https://pubmed.ncbi.nlm.nih.gov/11055546/
Quote from zerocool on August 25, 2021, 11:40 am@david For the record not discouraging anyone for doing a low vitamin A diet.
If you think I'm trolling that's fine...you can look at my profile, I've been a member on this forum for years now(longer than you David)...
1) "Vitamin A and iron supplementation is as efficient as hormonal therapy in constitutionally delayed children
conclusions Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty."
Source: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2265.2004.02034.x
2) "Testosterone glucuronide exhibited significant correlations with calories and vitamin A. This study suggests that dietary intake affects plasma sex-steroid levels in men."
Source: https://pubmed.ncbi.nlm.nih.gov/3360302/
3) "In this rodent study, it was noted that the testicular system of rats contains several receptor sites for vitamin A and that it can be stored in testicular Sertoli cells. What’s more interesting is that when the rodents diets were cut off from all vitamin A, testosterone production rapidly decreased (up to the point of where sexual organs literally atrophied), and estrogen exposure inside the testes rose rapidly (as humans share nearly identical testicular systems with Wistar rats, this becomes very interesting)."
Source: hyperlinked "rodent study"
4) "The decrease in the binding characteristics of PBRs in testes due to vitamin A deficiency was accompanied with a corresponding decrease in the levels of testosterone in plasma. These results suggest a close functional relationship of vitamin A with PBRs in testes."
Source: https://pubmed.ncbi.nlm.nih.gov/11055546/
I'm just starting to follow a low-VA diet and I'm not trying to persuade anyone to stick to it. But I would like to point out some potential mistakes in the studies you have cited.
1) I would like to see the full text of the study (I don't have access), but it seems that the doses of VA were quite low(6000 IU per week, I think many ordinary people consume so much per day) and the fact that iron is needed for hormone synthesis, etc.is really not news.
2,3) Serum testosterone levels are not very informative, there was a study on RPF in which serum testosterone did increase in mice after vitamin A supplements, but the size of the testicles decreased (which also usually correlates with testosterone levels, including in tissues).
4) The inability to produce RBP also suggests that mice are less protected from the teratogenic effects of vitamin A.
Quote from zerocool on August 25, 2021, 11:40 am@david For the record not discouraging anyone for doing a low vitamin A diet.
If you think I'm trolling that's fine...you can look at my profile, I've been a member on this forum for years now(longer than you David)...
1) "Vitamin A and iron supplementation is as efficient as hormonal therapy in constitutionally delayed children
conclusions Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty."
Source: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2265.2004.02034.x
2) "Testosterone glucuronide exhibited significant correlations with calories and vitamin A. This study suggests that dietary intake affects plasma sex-steroid levels in men."
Source: https://pubmed.ncbi.nlm.nih.gov/3360302/
3) "In this rodent study, it was noted that the testicular system of rats contains several receptor sites for vitamin A and that it can be stored in testicular Sertoli cells. What’s more interesting is that when the rodents diets were cut off from all vitamin A, testosterone production rapidly decreased (up to the point of where sexual organs literally atrophied), and estrogen exposure inside the testes rose rapidly (as humans share nearly identical testicular systems with Wistar rats, this becomes very interesting)."
Source: hyperlinked "rodent study"
4) "The decrease in the binding characteristics of PBRs in testes due to vitamin A deficiency was accompanied with a corresponding decrease in the levels of testosterone in plasma. These results suggest a close functional relationship of vitamin A with PBRs in testes."
Source: https://pubmed.ncbi.nlm.nih.gov/11055546/
There is plenty of evidence that VA, at least in the short term, increases the activity of a certain enzyme that converts pregnenolone to testosterone.
There is however absolutely zero evidence that VA is required for this enzyme to be produced, or exert its normal activity.
3) in the study about the testicular atrophy (https://royalsocietypublishing.org/doi/10.1098/rspb.1964.0017) the rats were fed an awful diet full of casein so it’s worthless and should be thrown out just based on that. The only thing it showed is that you can destroy testis by feeding retinoic acid to animals that are b-vitamin deficient but if you also give a b-vitamin-complex and retinol there won’t be atrophy.
Very curious that they only gave b-vitamins to the group that was given retinol but not to the group that was given retinoic acid alone. It’s almost like they were manipulating the methodology in order to make retinol look like a hero. A garbage study whatever the reason was.
There is a lot of talk about retinoic acid receptors in a lot of the of papers you linked. It’s important to remember that retinoic acid receptor is just a name. There are multiple ligands, there are many other things that bind to these same receptors. So even if their theories are correct and you need to have to hit those receptors with something it doesn’t have to be VA.
Quote from Даниил on August 25, 2021, 12:11 pmQuote from zerocool on August 25, 2021, 11:40 am@david For the record not discouraging anyone for doing a low vitamin A diet.
If you think I'm trolling that's fine...you can look at my profile, I've been a member on this forum for years now(longer than you David)...
1) "Vitamin A and iron supplementation is as efficient as hormonal therapy in constitutionally delayed children
conclusions Subnormal vitamin A intake is one of the aetiological factors in delayed pubertal maturation. Supplementation of both vitamin A and iron to normal constitutionally delayed children with subnormal vitamin A intake is as efficacious as hormonal therapy in the induction of growth and puberty."
Source: https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-2265.2004.02034.x
2) "Testosterone glucuronide exhibited significant correlations with calories and vitamin A. This study suggests that dietary intake affects plasma sex-steroid levels in men."
Source: https://pubmed.ncbi.nlm.nih.gov/3360302/
3) "In this rodent study, it was noted that the testicular system of rats contains several receptor sites for vitamin A and that it can be stored in testicular Sertoli cells. What’s more interesting is that when the rodents diets were cut off from all vitamin A, testosterone production rapidly decreased (up to the point of where sexual organs literally atrophied), and estrogen exposure inside the testes rose rapidly (as humans share nearly identical testicular systems with Wistar rats, this becomes very interesting)."
Source: hyperlinked "rodent study"
4) "The decrease in the binding characteristics of PBRs in testes due to vitamin A deficiency was accompanied with a corresponding decrease in the levels of testosterone in plasma. These results suggest a close functional relationship of vitamin A with PBRs in testes."
Source: https://pubmed.ncbi.nlm.nih.gov/11055546/
I'm just starting to follow a low-VA diet and I'm not trying to persuade anyone to stick to it. But I would like to point out some potential mistakes in the studies you have cited.
1) I would like to see the full text of the study (I don't have access), but it seems that the doses of VA were quite low(6000 IU per week, I think many ordinary people consume so much per day) and the fact that iron is needed for hormone synthesis, etc.is really not news.
2,3) Serum testosterone levels are not very informative, there was a study on RPF in which serum testosterone did increase in mice after vitamin A supplements, but the size of the testicles decreased (which also usually correlates with testosterone levels, including in tissues).
4) The inability to produce RBP also suggests that mice are less protected from the teratogenic effects of vitamin A.
Use sci-hub to get access to studies. They have an ever changing url. It’s also on the telegram chat app. You just post the url for a study abstract and it returns you the full study.
Thanks for the reply with something to back up your statements!
Regarding you being a member on this forum for a longer time than me, and that directly giving you seniority is a pretty weak argument since you probably know very little about me. So if you are wondering I have been following a low vitamin A diet since the beginning of 2020.
I found the complete first study from 2004 that you linked to at sci-hub.st with the DOI:
https://doi.org/10.111/j.1365-2265.2004.02034.x
Have you looked at more than the abstract of that 2004 study?
They looked at slow-growing pre-puberty boys and measured their testicles. I want to add that I think studying boys soon hitting puberty is probably among the worst category of humans to look at for most studies since they are known to have the possibility of insane growth spurs and they have tons of confounding factors from only the natural change of hormones. The study doesn't even try to look at any of them more than to see that everyone in the study starts out with about the same measured metrics they have decided to measure. They only controlled giving supplements to some of the groups, and diets were not at all controlled as per this quote about diet recall analysis:
"The only significant dietary modification was increased vitamin A and iron intake in artificial form. These artificial additives are not included in Table 3, which reports the dietary recall analysis."
Also note in Table 3 how they all seem to have eaten low zinc diets and zinc deficiency is a well-known cause for slow growth in humans, they even reference a study to that effect "Iron and zinc supplementation improves indicators of vitamin A status
of Mexican preschoolers" from American Journal of Clinical Nutrition, 71, 789–794. Munoz, E.C., Rosado, J.L., Lopez, P., Furr, H.C. & Allen, L.H. (2000)
Here is the best quote from the study showing how badly constructed this study is since it can't say if it was iron, iron+vitamin A or just vitamin A that caused some result:
"However, we must stress that we do not prove that iron did not have some effect on puberty in our patients as it was given concomitantly with vitamin A. It has also been shown (Vihenrvuori & Sipilia, 1994; Choe et al., 2000) that, during rapid growth in children, iron levels are depleted. Supplementation of 12 mg/day of iron ensures that the child receives the necessary amount required during rapid growth."
I probably won't look at any of the other studies that you posted since danill already commented on them and since you can't possibly have read this 2004 study you posted under 1) as per the last quote about them being unable to prove anything about vitamin A due to the study using an awful methodology.