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Dataset confirms that a vegan diet is dramatically better across a range of environmental measures (phys.org)

submitted 2 years ago by floofloof@lemmy.ca to c/science@lemmy.ml

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[+] commie@lemmy.dbzer0.com -11 points 2 years ago (1 children)

animals are fed parts of plants that people can't or won't eat. and cows eat mostly grass.

[–] PolyLlamaRous@lemmy.world 17 points 2 years ago (5 children)

Yeah and no. Cows eat about 2% of their weight each day. Over 98% of this comes from food that we grow for them. It's true that a lot of it we humans wouldn't eat, but we still grow it for them to eat. The idea of cows eating grass in a field and that's what they eat is extremely rare.

For the US as a example less than 1% of the cows feed is grass. The majority of things like soy (77% of what is grown and we could eat) goes to cow feed.

"There were about 92 million head of cattle in the United States at the end of 2015, with roughly 30 million head slaughtered that year. For perspective, the grass-fed industry currently slaughters about 230,000 head, or less than 1% of the total conventional slaughter."

[–] commie@lemmy.dbzer0.com 1 points 2 years ago

approximate percent of soybean that is oil = 20.00
percent of soy fed directly to animals = 7.00
percent of soy fed to dairy = 1.4
percent of soy fed to beef = 0.5
percent of soy fed to pets = 0.5
percent of soy fed to aquaculture = 5.6
percent of soy fed to pig = 20.2
percent of soy fed to poultry = 37.0
percent of soy that becomes human food = 20.00
percent of soy that becomes oil for food = 13.2
percent of soy that becomes soy milk = 2.1
percent of soy that becomes tofu = 2.6
percent of soy that becomes tempeh etc = 2.2
percent of soy that is fed to animals = 76.0
percent of soy that is used industrially = 4.00
percent of soy that becomes biodiesel = 2.8
percent of soy that becomes lubricants = .03
percent of soy that has other industrial uses = .07
percent of soy not fed directly to animals = 93.00
if all soy not fed directly to livestock were pressed for oil = (approximate percent of soybean that is oil / 100) * percent of soy not fed directly to animals
soy eaten not as oil = percent of soy that becomes soy milk + percent of soy that becomes tofu + percent of soy that becomes tempeh etc
if all soy not eaten directly by livestock and not as non-oil food is pressed for oil = (percent of soy not fed directly to animals - soy eaten not as oil) * approximate percent of soybean that is oil / 100

If we take 7% of all soy out because it's fed directly to animals, and another 6.9% is eaten, but not as oil, and 20% of each of the remaining beans are made of oil, we find 17.22% is the maximum amount of oil we could get if all the soy beans not fed to animals or eaten by people are pressed for oil.

It turns out that the chart shows 13.2% is oil for humans to eat, and 4.0% is used industrially (and these are all oil uses), totaling 17.2%,then basically all soy not eaten directly by animals or as various human foods is pressed for oil.

source https://ourworldindata.org/uploads/2021/02/Global-soy-production-to-end-use.png

[–] commie@lemmy.dbzer0.com 0 points 2 years ago

"grass fed" means they aren't grain-finisged, but most of their diet is grass until they get to the feedlot.

[–] commie@lemmy.dbzer0.com -1 points 2 years ago (1 children)

almost all soy is pressed for oil. what is fed to livestock is almost entirely industrial waste from that process.

[–] DarthFrodo@lemmy.world 5 points 2 years ago (1 children)

Using it to make plant-based meat alternatives or tofu or soy milk would be more efficient than feeding it to animals, where most of the nutrients and calories are used up by their metabolism.

[–] commie@lemmy.dbzer0.com -3 points 2 years ago (1 children)

yea. we do. but we don't use all of it for human food. i don't see anything better to do with the industrial waste than feed it to livestock.

[–] DarthFrodo@lemmy.world 1 points 2 years ago (1 children)

After extracting the protein and nutrients for plant-based products there's not much nutrition left to use it as animal feed though. It's probably not nutritionally appropriate for cows, pigs and chickens at that point. Using it for insect farming would seem more realistic to me, or as a growth medium for edible mushrooms.

[–] commie@lemmy.dbzer0.com 0 points 2 years ago

when you have a ton of soy cake, I guess you can decide what to do with it.