vitamin A

[RRM]

This thread is a spin off from this post: viewtopic.php?p=10496#10496

Hi Feral,

I hope you know that liver is extremely high in vitamin A, and that this may have very strong adverse effects if you eat too much of it?

[feral]

liver is high in vit A its not the portion which is important its the proportion between vit D and vit A get too much vit A only and you can suffer if you ged adequate supply with vit D you should be ok i think read articles about it but now cant rememberr exactly where but for shure they were good yup liver and yolks works just fine for me no cod liver added know there is much vit D but it my stomach dont feels good when eat it beside its a fish

[RRM]

liver is high in vit A its not the portion which is important its the proportion between vit D and vit A get too much vit A only and you can suffer if you ged adequate supply with vit D you should be ok

Intakes of over 25,000 IU may eventually (in 6 yrs) lead to liver cirrhosis. (study)
150 gram of ox liver contains about 25,000 IU of vitamin A.
Ive searched PubMed, but could not find any notion of vitamin D preventing vitamin A intoxication.

[feral]

i have read this study but find nothing interesting and proving its bad to eat liver .Too little information not enough to make opinion on the subject read this article its very good

http://www.westonaprice.org/basicnutrit ... osteo.html

its a lot of info mainly concerning osteoporosis and vit A but also some additional info about vit A and even carotenoids and how deficiencies in vit D vit E and vit K can lead to vit A intoxication

[RRM]

how deficiencies in vit D vit E and vit K can lead to vit A intoxication

Why is it that people only see the dangers of a lack of a certain nutrient, and not the dangers of excess?
Health is not just about consuming enough of every nutrient, its also about not consuming too much...
But if you think that eating liver on a daily basis is ok, just go ahead.

[feral]

Why is it that people only see the dangers of a lack of a certain nutrient, and not the dangers of excess?
Health is not just about consuming enough of every nutrient, its also about not consuming too much...

you havent read the aritcle you should do it i was trying to put it brief
so ill quote from the article

Rhode and Deluca showed that a mere amount of vitamin D equivalent to a daily human dose of just over 900 IU was able to turn off the negative effect of vitamin A on the serum calcium levels of rats, who as mammals are closer to humans than are chickens, even when the rats consumed amounts of vitamin A that exceeded the equivalent of a daily human dose of 5,000,000 IU.

guess thats a lot vit A even knowing that the rats arent our closest relatives
i`m not trying to make you eat liver.we were just talking can a man intoxicate himself eating not too little of it lets say about 300g per day which for me is far too much the experimental data show that he can even if he consumes relatively small amounts if he is not consuming enough vit D rich foods

[RRM]

Rhode and Deluca showed that a mere amount of vitamin D equivalent to a daily human dose of just over 900 IU was able to turn off the negative effect of vitamin A on the serum calcium levels of rats, who as mammals are closer to humans than are chickens, even when the rats consumed amounts of vitamin A that exceeded the equivalent of a daily human dose of 5,000,000 IU.

This is specific for the direct effects of vitamin A on serum calcium levels, NOT about the toxicity of elevated levels of vitamin A and the devastating effects for your liver on the longer run.
Its an experiment with a short time span. Adverse effects on the liver have not been measured.

[feral]

This is specific for the direct effects of vitamin A on serum calcium levels, NOT about the toxicity of elevated levels of vitamin A and the devastating effects for your liver on the longer run.

now i think you still havent read the article its not too long
ill quote again from article

Research that examines the feeding of high doses of more than one vitamin simultaneously reveals that toxicity is dependent on reactions between different nutrients. For example, studies in rats, turkeys, and chickens have demonstrated that vitamin A both decreases the toxicity of and increases the dietary need for vitamin D, while vitamin D both reduces the toxicity of and increases the dietary need for vitamin A

so here for me there can be made a general conclusion.Exsesive vit A intake can lead to osteoporosis and liver damage over time.And we ingest enough vit D and disable the toxicity of vit A no osteo occurs.So we can assume there will be no liver damage either.
for me if you are sick your whole body is sick not just a single part or organ.saying well i`m just fine only my liver bothers me sounds strange to me.i look for more integral way of thninking of disease and nutrition.

and another argument for this argue.animal carnivores after killing a prey eat first the internal organs then after that the fat and most of the time dont touch the lean meat(think lions are exception but they sleep alot )
they dont suffer vit A intoxication.humans as being hunter-gatheres for long period of time are carnivorous animals.so they would probalby eat the internal organs and the fat of the prey.most of the still existing hutner gatherers societies eat raw or lightly cooked liver.its the first thing they do after animal is killed.they evaluate the liver as most vital food even giving fertility(quite opposite from modern recomendations for pregnant woman)most of those societies eat the animal fat raw and consume the lean meat cooked.they dont suffer from vit A intoxication.this the practical side of the things.some theory can sound very good on paper but when it cannot be proven experimentaly why stick to it?its not true no matter what the papers say.

[RRM]

So we can assume there will be no liver damage either.

A potential dangerous assumption, and therefore unwise.

animal carnivores after killing a prey eat first the internal organs

Predators do.
Cows eat grasses.
Chicken eat raw grains.
We are humans. We are very different regarding nutrient metabolisms. Predators produce their own vitamin C, for example.

humans as being hunter-gatheres for long period of time

but how much internal organs did they eat?
How often did they get to eat liver?

[feral]

A potential dangerous assumption, and therefore unwise.

So i`m unwise

We are humans. We are very different regarding nutrient metabolisms. Predators produce their own vitamin C, for example.

To me this sound like we are humans(and we are also carnivores) and we are different from other carnivores.How come?And how we differ in our nutrient metabolism from other carnivores?And how vit C corelates with this?

but how much internal organs did they eat?
How often did they get to eat liver?

i`ll quote from article

As for concerns about vitamin A, these stem from studies in which moderate doses of synthetic vitamin A were found to cause problems and even contribute to birth defects. But natural vitamin A found in liver is an extremely important nutrient for human health and does not cause problems except in extremely large amounts.

In adults, according to the Merck Manual, vitamin A toxicity has been reported in Arctic explorers who developed drowsiness, irritability, headaches and vomiting, with subsequent peeling of the skin, within a few hours of ingesting several million units of vitamin A from polar bear or seal liver. Again, these symptoms clear up with discontinuation of the vitamin A-rich food. Other than this unusual example, however, only vitamin A from megavitamin tablets containing vitamin A when taken for a long time has induced acute toxicity, that is, 100,000 IU synthetic vitamin A per day taken for many months.

so another assumption maybe synthetic in moderate doses and natural vit A in mega doses causes toxic effects

i`ll quote again from the same article

The putative toxic dose of 100,000 IU per day is contained in two-and-one-half 100-gram servings of duck liver or about three 100-gram servings of beef liver. From the work of Weston Price, we can assume that the amount in primitive diets was about 50,000 IU per day

the whole article can be found here
http://www.westonaprice.org/foodfeatures/liver.html

so assumption again eating 150g beef liver every day is harmless.

[RRM]

how we differ in our nutrient metabolism from other carnivores?And how vit C corelates with this?

Vitamin C is a nutrient, and the mere fact that predators produce their own vitamin C, proves that there are essential differences between us and other mammals, including predators.
Every specie is in its nutrient metabolism adapted to its natural foods. Predators will have a much greater tolerance for high vitamin A intakes.

natural vitamin A found in liver is an extremely important nutrient for human health and does not cause problems except in extremely large amounts.

Thats a nice statement; all vitamins are essential, but did they do tests proving that a daily high intake of vitamin A has no adverse effects on the liver?

vitamin A toxicity has been reported in Arctic explorers who developed drowsiness, irritability, headaches and vomiting, with subsequent peeling of the skin

Indeed; It is well known that Inuit will not eat the liver of polar bears or seals, for obvious reasons.
And from eating just 4 oz (113 g) fish that includes fish liver, you may already get ill. (including blurry vision)
http://www.pubmedcentral.nih.gov/picren ... obtype=pdf
From
http://www.provet.co.uk/petfacts/health ... tamina.htm
"Taking excess vitamin A supplement, or eating too much liver are common causes of toxicity"

The putative toxic ...about three 100-gram servings of beef liver.

so assumption again eating 150g beef liver every day is harmless

So, the putative toxic dose is 300 gram beef liver, and therefore 150 gram is safe? That doesnt make sense because in this you disregard long term effects on your liver. Less than the toxic dose does not at all mean a safe dose when taken for years....

From: http://www.prn2.usm.my/mainsite/bulleti ... sun43.html

Since vitamin A is stored in the liver, chronic ingestion of megadoses may result in hepatic toxicities. The range of vitamin A doses leading to liver damage vary from 15,000IU per day to 1.4 million IU per day, with an average daily toxic dose of 120,000IU per day.
...
an intake of 25,000IU per days is considered nutritionally high and conveys some risk of toxicity

[feral]

ihi back after a vacation
so to get to the point
i cant still see the connection between vit C prouction and liver consumption.
our digestive systems are much the same.how we differ from them in our metabolism?
i have read those articles but first ill quote from here www.westonaprice.org/foodfeatures/liver.html

In adults, according to the Merck Manual, vitamin A toxicity has been reported in Arctic explorers who developed drowsiness, irritability, headaches and vomiting, with subsequent peeling of the skin, within a few hours of ingesting several million units of vitamin A from polar bear or seal liver. Again, these symptoms clear up with discontinuation of the vitamin A-rich food. Other than this unusual example, however, only vitamin A from megavitamin tablets containing vitamin A when taken for a long time has induced acute toxicity, that is, 100,000 IU synthetic vitamin A per day taken for many months.

Thus, unless you are an Arctic explorer, it is very difficult to develop vitamin A toxicity from liver. The putative toxic dose of 100,000 IU per day is contained in two-and-one-half 100-gram servings of duck liver or about three 100-gram servings of beef liver. From the work of Weston Price, we can assume that the amount in primitive diets was about 50,000 IU per day.

in those studies you gave there is nothing about vit D consumption related to vit A toxicity.
I`ll quote from article

Since vitamin A is stored in the liver, chronic ingestion of megadoses may result in hepatic toxicities. The range of vitamin A doses leading to liver damage vary from 15,000IU per day to 1.4 million IU per day, with an average daily toxic dose of 120,000IU per day.

its a very big difference so we can assume that some people of the control group have a high vit D availability in their body.also i can note that some people are eating more liver than others.so they are used to it.any time you represent some new food to your body you should expect a reaction.in most cases bad reaction with ill like effects.I`ll give an example with a fruit(cause i like fruits ) i can still remember the day that i ate my first wild apple.After eating three of them my mouth was like i have pins and needles.And this feeling lasted for two more days.So is it bad eating wild apples?Well i think its not.After you get used to them they get to be very tasty.Hey you can even combine them with liver
from my expirience i can say that i have eaten 1kg of beef liver with no adverse effects in short turn.but that was when i previously introduced it to my diet.
after all that writing i would like to take a more simplistic view of the theme.so to put it simple you say that eating liver is bad for your liver.to me it sounds strange.so some one can say that eating brain is bad for your brain(too much cholesterol) but brain is rich in omega fats(they are very good for your body and especially for your brain).or eating hearts is bad for your heart(too much cholesterol again and you die from heart attack).
or eating animal bones is bad for your bones?
i think that you`ll argue on the last one since i have read an article of yours.

[RRM]

If you take in extremely much of a certain nutrient that may have toxic properties when absorbed in excess, there is a substantial risk that your body may not be able to decrease the absorption rate accordingly.
Therefore, we advice against eating liver because its extremely high in vitamin A, in as much as we advice against eating oysters as they may be extremely high in zinc, and against consuming linseed oil as it is extremely high in linolenic acid (an omega 3 fat).

It is known that prolonged elevated levels of vitamin A in the blood has adverse effects on liver health.
So, the question is: How much vitamin A can we consume without this resulting in elevated blood vitamin a levels?

Some people claim it takes a single dose of 100,000 IU, others 25,000 daily for years. The toxicity of vitamin A totally depends on how much ends up in the blood, which is very much individually different.
You dont know if / to what extend the vitamin A that you consume results in elevated levels in your blood.
Fact is that liver is extremely high in vitamin A, and that when you ingest very much vitamin a daily, this may result in elevated levels, and on the long haul in liver damage.

You say you think its not a risk, but you dont know how much of the vitamin A is absorbed.
If you insist on keep on eating liver daily, I advice you to get your blood vitamin A level checked every now and then, as well as your liver.

But why take that risk at all?
Why ingest extremely much vitamin A if there is no need to?
Why force your body to lower the absorption rate as much as it can, not knowing if it can lower the absorption rate sufficiently?

is it bad eating wild apples?

No, because unlike liver, apples dont contain extremely much of any nutrient; they are well balanced, nutrients wise.

[Erasmus331]

Hi… that was great stuff.. I

[sunpower9]

intake of vit A and menstrual cycle connected...eating lotsa vit A supposed to reduce bleeding or maybe stop it completely (weston price foundation) so eating lotsa egg yolks does definitely help women's cycle...how many do you like eating or how many do you eat everyday ? for the ladies out here....