Quote from tim on November 1, 2021, 5:10 am

@ggenereux2014

Although you and I disagree on the theory of “vitamin A” being essential, I think we are in alignment on other aspects of this topic. That is 1) vitamin A toxicity is far more prevalent than commonly acknowledged.

Yeah we aren't going to agree but yes on point (1) we can both 100% agree.

But, if we could overturn this claim of "it's a vitamin", then we might have a (admittedly very slim) chance of stopping the supplementation of it in common foods.

Fortification goes against their own data which shows that almost nobody in the USA is deficient and far more have Hypervitaminosis A than VAD so I believe that pointing this out is the best approach.

Quote from Retinoicon on November 1, 2021, 4:26 pm

Quote from ggenereux on October 31, 2021, 7:29 pm

I’m not planning on changing my diet this year other than that I’ve decided to go exclusively with bison over beef. This change is not for any big reason.  It’s just a personal choice since I know the rancher that raises the bison. A minor benefit is that bison is lower in fat compared to beef, and I’ll therefore be slightly lower in my (trivial) vA intake. 

Grant, I respect you but I don't think grass-finished bison is low in retinol. The most recent evidence points to grass-finished beef being high in retinol. Also, fat from grain-finished animals likely has lower retinol content than muscle meat from grass-finished animals. I do not think you have ever been on a low vitamin A diet if you have been consuming grass-finished bison, I am sorry to say.

The most direct reference on grass-fed versus grain-fed beef using presumably the most recent meausrement techniques is

β-carotene and retinol contents in the meat of herbivorous ungulates with a special reference to their public health importance

https://pdfs.semanticscholar.org/3da5/0ad6461e9641e89dfebc1ade9a76a88eedbd.pdf

Look at Figure 3 and at the absolute levels of retinol. It looks to be 10 mcg of retinol per g of tissue. 

The other reference is

Effects of feeding β-carotene on levels of β-carotene and vitamin A in blood and tissues of beef cattle and the effects on beef quality

https://doi.org/10.1016/j.meatsci.2015.07.019

Look at the left column of Table 5 and how the retinol levels decline from 3 to 4 to 5 months of grain-finishing and how the subcutaneous fat at 5 months of grain-finishing has four times lower retinol than the muscle meat at 4 months of grain finishing. Yes, even the control group grain diet in the left column got some vitamin A supplementation in the feed, but the remarkable thing is how vitamin A goes down so quickly with five months of grain finishing. With your grass-finished bison, you are at some extrapolated 0 months of grain-finishing, which perhaps has higher retinol than the three months of grain-finishing in the figure. The muscle meat at three months of grain-finishing is 36 mcg of retinol per gram of tissue, which is quite a lot of retinol. 

I myself consumed grass-finished bison (I cannot find grain-finished bison for mail order) during a week this summer and had an uptick of symptoms I associate with high vitamin A. It wasn't any different in terms of symptoms than grass-finished beef, for me at least. 

Quote from Jiří on November 1, 2021, 9:08 pm

@jeremy I agree. true low vit A diet would be something like boiled chicken/turkey breasts, maybe white fish like cod, egg whites and that's it. If someone eats grass fed red meat every day. It's far from "zero" vit A intake..

Quote from salt on November 2, 2021, 4:47 am

Grass fed meat definintely has significant levels of VA but I think Grant's blood tests show that despite eating grass fed meat (and red beans) his diet was still low enough to deplete VA over time, his blood VA levels still went down to almost nothing.

Quote from salt on November 2, 2021, 5:02 am

Quote from Max on October 27, 2021, 1:48 am

1. If this theory were true, we would never see people cure their autoimmune diseases while eating a high Vitamin A diet. However, there are countless of stories of people doing just that. I know tons of people that cured their eczema while juice-fasting (lots of beta-carotene) or on the Paleolithic Ketogenic Diet by Paleomedicina (lots of liver, so lots of Retinol) or on a carnivore diet with lots of butter and egg yolks or on a vegan diet with lots of fruit and vegetables.

 

2. If this theory were true, the foods highest in Vitamin A would trigger people the hardest. But this is not the case either. I myself have sebderm and I confirm that tomatoes, bell peppers and milk a clear trigger foods. Yes, they have some Vitamin A, but this is obviously not the problem with them. Because the following are some foods that I can eat in huge amounts without ever being triggered by them: Carrots, sweet potatoes, pumpkin, spinach. These foods have a lot more beta-carotene than a tomato and I can eat them in huge quantities and never got any reaction to them. I also never had a clear reaction to butter or egg yokes, which are quite high in Retinol. However, when I drink just ONE glass of milk my skin gets destroyed (milk is not supplemented with Vitamin A in Germany). This again shows: It is not the little bit of Retinol in the milk.

 

 

3. Countless studies show that up to 5 servings of fruits and vegetables a day reduce the risk of pretty much all diseases and reduce all cause mortality. Also countless of studies show that health markers improve when one increases fruit and vegetable consumption. If beta-carotene was this toxic, this wouldn’t be possible. No, I admit I’m into conspiracy theories myself and I’m well aware that we are lied to sometimes, but I’m pretty sure these studies are not all fake. (And btw, these are controlled studies and not some worthless epidemiology studies that don’t factor in unhealthy user bias). On the other hand there are more than enough studies that show how grains and vegetable oils, which are much lower in beta-carotene than fruits and vegetables, are harmful.

1. I think the theory is that the acute effect of eating a VA rich meal is actually to depress VA levels in the blood, as the body desperately tries to shunt it into the liver and other tissue. There is also a suppressant effect on the retinol -> retinoic acid conversion. So, paradoxically, short-term, when eating a lot of VA you might lower blood levels off it, at least until your liver is completely overburdened with it. This idea would also explain why VA foods can give such good symptom relief for all kinds of things. But the returns are diminishing quickly. In regards to skin it will be helpful for as long as your skin can handle the increased turnover that VA induces. I've never heard of anyone long-term curing for example arthritis while eating a diet high in liver.
2. It is the case, for me and others as well. It sounds like you might be allergic to milk.
3. No. In these studies they are comparing a high-VA diet that is low in fruits and vegetables vs a high-VA diet that is high in fruits and vegetables, and the group that eats more fruits and vegetables seem to be doing better, probably because they are getting plenty of nutrients that they didn't get before. VA intake being almost the same.

Quote from ggenereux on November 2, 2021, 10:05 am

Hi @jeremy,

Thanks for posting the two studies.

The reference I’ve been using for VA content of Bison is:

https://fdc.nal.usda.gov/fdc-app.html#/food-details/577188/nutrients

It reports that bison is 0 IU Vitamin A / 100 g.

But, I have no idea how accurate that USDA figure is. 

Regarding the first study from Japan, the “Buffalo” they are referring to is a water buffalo, and that’s quite a different animal than a North American Bison.

Since vitamin A is a fat soluble molecule it is mostly likely to be found only in the intramuscular fat content of meat. Since bison is very lean compared to beef, in theory it shouldn’t be a significant amount.  

But, I have no way of knowing for sure how much I’m really getting.  Hopefully, someday I’ll be able to get an updated VA serum test and that will provide more insight.

 

Quote from Retinoicon on November 2, 2021, 1:15 pm

 

Hey @ggenereux2014,

Yeah, I wasn't even looking at the buffalo in the Egyptian/Japan study, just the direct comparison of grass-finished vs grain-finished beef, both from Zagazig, Egypt. I grass-finished beef is a better comparison to bison. 

On the USDA database showing 0 values of vitamin A for bison, that data was provided by the company, Rocky Mountain Natural Meats. We don't know whether the company actually tested vitamin A or just assumed it was 0, which happens all the time for values reported as 0 for meat in nutritional databases. For example,  I have read that assuming a value of zero happens with vitamin C in meat: the databases assume vitamin C in meat is zero but academic studies show it is not zero. If the company did test vitamin A, we don't know what procedures were used, unlike in an academic study.

On whether vitamin A can be stored in leaner meat, I am not expert but I would predict so. A cow's liver has very little fat and a huge amount of vitamin A, right? If I remember right, your arguments about the faulty studies of the essentiality of vitamin A in animals used protein (casein was it?) that was mixed in with retinoic acid, or something. Certainly the Chinese study cited above shows plenty of vitamin A in beef muscle meat at three and four months of grain-finishing with baseline supplements: 36 mcg retinol/g of tissue. At that level, the RDA of 900 mcg would be achieved by only 25g of meat, which is a trivial amount. At the 10 mcg/g of tissue in the grass-finished cows from Egypt, 900 mcg would be achieved by 90g of meat, which is likely less than you eat in a day. 

Quote from wavygravygadzooks on November 2, 2021, 2:26 pm

@jeremy

I don't see in that study a description of how the meat was sampled.  Do you know how it was?

How did they select the muscle meat from the carcass?  Where on the carcass did it come from?  Was there a standard quantity of fat contained in the muscle for each sample?  It seems like we have no idea how much fat was contained in the samples.

Liver is listed as 24% fat, 64% protein, 12% carbs.  It definitely has fat in it, and probably more than numerous different cuts of muscle meat.

Quote from ggenereux on November 2, 2021, 6:26 pm

Hi @jeremy,

I don't know what quite to make of that. I need some time to dig into other references for the typical vitamin A content in muscle meat.

Sure would be nice if we had access to a reliable lab and start doing our own analysis.