Don't lose sleep over individual contributions. It's the corporations that need to change behaviour. Put your energy into fighting them.
Corporations are only producing things that people want. I'm all for strict regulation, but "blame the corporations and not yourself" is a huge copout. Especially when reducing your meat consumption is one of the single most impactful things you can do to reduce your effect on the climate.
Corporations caused this problem by buying politicians that created regulations favorable to them. They are the only entities big enough to fix this problem, for instance, by recapturing gases like methane. I refuse to be held responsible for simply eating.
Not an answer, and I won’t get a lot of upvotes for saying this, but if your plan for saving the world is for people to change their behavior en masse, you’ve already lost. And we need population-level change in order to have a meaningful impact.
The way we get people off meat is by making the alternatives more (or equally) tasty, convenient, familiar, and affordable. The day we do that, the war is won. There will be some stragglers (of the “beef! murica!” variety) but not many.
We’ve made inroads. Indian food is delicious, way more popular in the West than when I was growing up, and vegetarian-inclined. Vegetarian burgers are more popular and varied than ever. New meat substitutes are being invented all the time. People are interested, but there’s not a well-lit path to vegetarianism for working-class folks just yet.
If you want to eat less meat, do it. But also, find some good meatless recipes and cook them for/with your friends. If they add those to their rotation and pass them along, that’s the kind of thing that can build toward change.
Danish research from March 2025:
255 grams per week. That's the short answer to how much meat you can eat without harming the planet. And that only applies to poultry and pork.
Beef cannot be eaten in meaningful quantities without exceeding planetary boundaries, according to a scientific article published by a group of DTU researchers in the journal Nature Food. So says Caroline H. Gebara, postdoc at DTU Sustain and lead author of the study.
American study from 2016:
Abstract
[...]
Transitioning toward more plant-based diets that are in line with standard dietary guidelines could reduce global mortality by 6–10% and food-related greenhouse gas emissions by 29–70% compared with a reference scenario in 2050.
American study from 2022:
Based on the model, published in the open-access journal PLoS Climate, phasing out animal agriculture over the next 15 years would have the same effect as a 68 percent reduction of carbon dioxide emissions through the year 2100.
This would provide 52 percent of the net emission reductions necessary to limit global warming to 2 degrees Celsius above preindustrial levels, which scientists say is the minimum threshold required to avert disastrous climate change.
the American study from 2022 is just warmed over tilman Clark (that American study from 2016), and the Danish study also depends on tilman Clark. so we should look at their methodology.
I did.
they compare a wide range of data from lca studies, even though this violated the best guidance on lca data.
lca studies are a bit like grand juries: the person designing the study can pretty much get any result they want.
and since these studies are all disparately methodized, you cannot combine them.
it's possible the conclusions are correct, but these papers are not sufficient evidence to be believed.
I don't have full access to the danish study, so I will have to take your word for it.
I do see that Tilman D, Clark M (2014) Global diets link environmental sustainability and human health. Nature 515(7528):518–522. is referenced in the 2016 study and the 2022 study.
the danish study is actually worse in some ways. it additionally cites poore-nemecek 2018, who themselves referenced tilman-clark, but egregiously gathered even more lca meta-analyses, and created something of a meta-meta-analysis of lcas. it's bad science all the way down.
Do you have any links for someone who wants to read more about these LCA and why they're not combinable?
hilariously, you can read the references from poore-nemecek, where the meta-studies they cite, themselves explain the problems with combining lcas, but then say "we're gonna do it anyway".
understanding how lca studies are conducted should be sufficient to understand why meta-analyses are misuses of the data, and the wikipedia article about lcas does a pretty good job of explaining the issues with the methodologies
255 grams per week is a lot more than I'd expect. Just for reference: the DGE - German Nutrition Society - recommends limiting intake of meat and meat products of not more than 300 grams per week, which is based on health aspects rather than environmental.
Google says livestock production creates 11-20% of global human co2 emissions. Even If we could make that disappear, it’s not enough
Meanwhile energy production is 73% so it’s critical to focus there
Realistically there is to switch to zero for any category of emissions so the only right answer is to cut as many as possible as much as possible
This isn't going to be a popular answer, but the only meats I don't feel guilty about eating are those that come from my family's farms, their, neighbors farms, or the wild game my family hunts. Commercial, large scale agriculture is damaging in many ways, but for most people who choose to eat meat it's very difficult to avoid. We need to advocate for a more localized food supply for so many reasons.
Just upvoting because it's a good question. I often find myself wondering just how much "X" can I consume before I should reign it in for the betterment of the planet. I'd like to be able to say I left earth better than I found it. Mainly thinking about things like gasoline, but food should certainly be on that list as well. Consuming zero of everything isn't a solution, but figuring out how much is okay - yeah, that's tough.
For the most part, not only does vegansim have the biggest positive impact on the environment that can be made with a personal choice, the animal products industries are like the third biggest contributor to climate change after energy (coal, oil, gas, etc) and manufacturing. Plus, as most farm land in the world is used for animal feed, it would free up land for reforestation.
P.s When talking about GHG emissions, it's a really bad idea to use % of total emissions as an indicator of impact. Livestock produce plenty of methane, which is roughly 84 times more impactful than carbon dioxide on the short term (20ish years) but carbon dioxide is more impactful over the long term (centuries) as it does not break down as quickly.
not only does vegansim have the biggest positive impact on the environment that can be made with a personal choice
there simply isn't any reliable data to support this claim.
There is:
https://www.wri.org/insights/climate-impact-behavior-shifts
Other than going car free (not possible in many countries where roads are just not bikable or walkable) not flying (yeah, you probably shouldn't and personally I rarely ever do) and switching your home to green energy (again, not really possible in some countries plus high up fron costs keep it impossible for many) the biggest impact is achieved through veganism.
going car free ...not flying ... switching your home to green energy ...veganism.
there are probably a thousand other things people could do. this study, for instance, didn't account for the impact of sabotaging fossil fuel extraction, refinement, or transportation infrastructure. almost anyone can turn a valve. by limiting the scope of this study to consumer choices, they have chosen to artificially limit the possibilities.
That is illegal. while you can choose to do illegal things, it just makes you look like a troll to suggest it as a viable option.
there are still probably thousands of options besides the four proposed.
Avoiding one long flight probably saves more carbon than a year of switching from eating meat to eating vegan. Also as others pointed out, not having kids would be by far more impactful by default.
Mmmm, meat. I typically enjoy 2 big, juicy burgers and one nice size steak (12oz minimum) per week.
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