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Conventional beef vs grassfed beef
The color of fat is going to be more so dictated by the breed of the cow. Although any grass fed beef will have more vA than its grain fed counterpart, that doesn't mean the absolute amount is going to be significantly higher.
Here is a study exploring the quantity of beta carotene in the fat of various cattle:
https://www.researchgate.net/publication/266288693_Genetics_of_Fat_Colour_in_Cattle
You sound like you're straight out of the ray peat forums with your omega3 demonization. Grass fed beef will have a better nutrient profile across the board, including all the other fat soluble vitamins that should help metabolize whatever vA you get from the beef. And, to paraphrase what's written above, not all cow breeds are shit beta-carotene converters.
I would like more information on the relationship between fat color and vitamin A content. I agree the yellow color is likely beta carotene. But the retinol in beef muscle meat or beef fat is much higher than beta carotene and it is the retinol that is relevant for health. A cow could have high retinol and perhaps the fat would still be white. What if the cow has been given vitamin A (retinol) supplements? Would the fat still be white or would it be yellow?
Quote from Moebius on May 29, 2021, 10:18 amQuote from Jiří on May 29, 2021, 9:32 am@jeremy beef from factory farming has white fat. Grass fed beef has yellow fat because it's full of vit A..
There is an old book, from before the time of grain fed beef, that specifically said not to eat the fat of animals bodies. Now we know why.
I doubt people were purposefully avoiding the fat of animals throughout evolution, as most game meats are lean to begin with, which is another arrow to the knee for all the keto gurus out there.
Quote from Retinoicon on May 29, 2021, 10:22 am
A cow could have high retinol and perhaps the fat would still be white. What if the cow has been given vitamin A (retinol) supplements? Would the fat still be white or would it be yellow?
That is indeed a problem of its own, and I am tempted to say that vA supplementation serves as a better explanation for the negative consequences people experience when eating various kinds of beef.
Quote from BeefWizard on May 29, 2021, 10:21 amThe color of fat is going to be more so dictated by the breed of the cow. Although any grass fed beef will have more vA than its grain fed counterpart, that doesn't mean the absolute amount is going to be significantly higher.
Here is a study exploring the quantity of beta carotene in the fat of various cattle:
https://www.researchgate.net/publication/266288693_Genetics_of_Fat_Colour_in_Cattle
You sound like you're straight out of the ray peat forums with your omega3 demonization. Grass fed beef will have a better nutrient profile across the board, including all the other fat soluble vitamins that should help metabolize whatever vA you get from the beef. And, to paraphrase what's written above, not all cow breeds are shit beta-carotene converters.
Looks like you forgot (again) to post the evidence about grass fed beef being more nutritious. Ray Peat is definitely correct about PUFAs, omega 3s included. Vitamin E makes your liver store more Vitamin A btw, so if it grass fed beef fat has more vitamin E then that is just yet another argument against it.
@jeremy My understanding is that non-oxidized retinol/al dosn't really have a color whereas beta-carotene is always colorful. If the fat is not white then it's probably beta-carotene you're seeing.
I am not sure about beef cattle breeds but the retinol and carotene content in cow's milk varies rather significantly between the different breeds. The Holstein is currently the most widely used dairy cow. But many years ago the Guernsey and the Jersey were the dominate breed......... especially for a "family milk cow".
On the link down bellow, on the 5th page down you can see the Vitamin A and and carotene content of butterfat between the different dairy breeds. This chart was for the spring and summer months. So, during the the winter months, the milk could have contained even less retinol and carotene unless they were given something that contained Vitamin A or carotene. Sun dried hay was probably relatively low in carotenoids.
The Holstein dairy cow is an efficient converter of carotenoids to retinol. The Guernsey and Jersey dairy breeds are less efficient at converting carotenoids to retinol. The milk and butterfat from a Holstein dairy cow is HIGH in retinol but fairly low in carotene and thus the Holstein produces milk that is white but loaded with retinol. But a Guernsey dairy cow produces milk that is much lower in actual retinol content but is higher in carotene content and thus the Guernsey produces milk that is more yellow in color but is much lower in actual retinol.
I looked back at the Chinese study of beta carotene supplementation of grain fed cattle, linked below. The title 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". A measure of "quality" is the color of the fat. The link is
https://www.sciencedirect.com/science/article/abs/pii/S0309174015300632?via%3Dihub
Here are my current thoughts on this study:
- Beta carotene supplementation did not make the fat yellow. Table 6 is about the color of the fat and in no case was there a significant change in fat color from beta carotene supplements. Also, the same table shows that was not decline in the yellowness of the fat from the decline in all tissue retinol levels, apparently due to grain feeding.
- From Table 5, it is still the case that retinol levels in muscle meat of cattle not getting supplements and eating grains (corn mostly) for five months is much, much higher than in previous studies and in FDA-style nutritional databases.
- I was wrong before about beta carotene supplements being a huge deal for muscle meat retinol. I wasn't looking at the all the values in Table 5. Even the control group (no beta carotene supplementation) has very, very, very high muscle meat retinol after three months of eating grains. But after two more months of eating grains (corn) muscle meat retinol goes down to the levels mentioned above in point #2. Probably what happened is both supplemented and non-supplemented cows were eating green grass before the grains started up and it took five months of eating grains for the muscle meat retinol values to come down to the still-high levels mentioned above in point #2.
- While the high levels of all cows compared to previous studies in point #2 are worrying, the takeaway in point #3 is that it requires five months on a feedlot eating grains to get the muscle meat retinol levels down.
- The interpretation of the beta carotene supplements in #3 is that they go directly to retinol in the liver. Do not eat the liver of animals getting beta carotene or vitamin A supplements. This finding that supplements go directly to the liver is somewhat inconsistent with the interpretation in #4 that green grass beta carotene was covering to retinol in the muscle meat and fat in addition to the liver. This is confusing.
- The bottom line was that these results on grain-finished cattle suggest to me that eating green grass with beta carotene raises muscle meat retinol and fat retinol and supplements with beta carotene raise only liver retinol. I don't understand completely understand how these results are compatible with each other, but that's my take from Table 5. This suggests that grain finished muscle meat is better than grass fed muscle meat for vitamin A detox, even if the grain fed cows are fed supplements. Also, Table 6 shows that fat color is not closely related to fat retinol content or liver retinol content.
- It is still unclear whether the high muscle meat retinol levels in Table 5 (and the study on Egyptian cattle discussed upthread) mean that beef in general is not a good vitamin A detox food.
- The role of bison muscle meat in vitamin A detox is unclear as most bison are fed grass and not grains. Getting bison from a northern climate like Grant's home of Alberta would reduce the amount of green grass and looking for grain finished bison would be even better.
This is complicated!
In modern times, in some circles, grassfed is considered better than grainfed but wouldn't it be natural for a herbivore to eat grain? After all, grass seed heads are grains. And wouldn't it be unnatural for an herbivore to just eat grass (the leafy green part of grass).
Here is a video of cows in a field of tall grass. If you notice they eat the seed head (grain) and they appear to love the grass seed head.
Historically and in the wild, herbivores such as bison or cows that are allowed to roam in vast open lands would have probably ate alot of seed heads/grain. Although, in modern agriculture the pasture grass fields may not be allowed to develop a seed head because the cows are constantly eating it down and preventing the grass from forming a seed head...... just like mowing your yard. Cows are fenced in so they have to eat what they have access to and can only roam as far as the fence will allow. But in the past cattle and other herbivores probably had more readily access to grass that had formed seed heads because they were not constantly grazing over the same grass field.
So, to me, it may be unnatural for a cow or a buffalo to just eat strictly the leafy part of a grass stalk. The eating of grain may have been a natural part of an herbivores diet.
That is a completely new take on things for me, Chelan. Thanks! The downside, of course, is that these grain fed cows have all sorts of other bad things put into them. I just went to a local supermarket and picked up some grain fed meat. My plan as of this moment is that I will eat grain fed meat until I do sufficient vitamin A detox, then possibly add back in some grass fed meat if I feel I can handle the vitamin A load, which might be significant based on that Chinese study.