Tag Archives: ghg emissions

One Bite at a Time – Part 3!

Lindsey Gallagher (they/them) is a non-binary nonfiction writer from Shelter Island, New York. They are currently pursuing their MFA at Northern Arizona University. They serve as the Editor-in-Chief of Thin Air Magazine and teach English Composition. Their work can be found in The Oval and The Palhouse Review. Outside of writing, they enjoy running and outdoor adventures of many sorts.

The Many Benefits of Plant-based Diets!

Welcome back! Last week I talked about some pretty terrifying numbers in terms of the impact animal agriculture has on the planet. Now it’s time to talk about the potential a plant-based diet has to help reduce climate change, along with some other benefits to humanity and animals!

Combating Climate Change

Greenhouse Gas Emissions

Getting rid of animal agriculture and substituting it with plant-based diets is “our best and most immediate chance to reverse the trajectory of climate change,” say scientists at Stanford and UC Berkeley based on a recent model

Perhaps the biggest impact a move to a plant-based diet will have is on greenhouse gas emissions. The model referenced above is just one piece of evidence among many on how emissions would change. The model, created by scientists at Stanford and UC Berkeley, sought to determine what the impacts on greenhouse gas emissions would be as a result of transitioning away from animal agriculture. The researchers concluded, a global move to a plant-based diet “would effectively halt the increase of atmospheric greenhouse gases for 30 years and give humanity more time to end its reliance on fossil fuels” (Than). Based on researchers Patrick Brown and Michael Eisen’s estimations, getting rid of animal agriculture could “reduce net emissions by the equivalent of around 1,350 Gt CO2 this century. To put this number in perspective, total anthropogenic CO2 emissions since industrialization are estimated to be around 1,650 Gt” (Eisen and Brown). But the biggest finding from the model is that “eliminating animal agriculture has the potential to offset 68 percent of current anthropogenic CO2 emissions.” That is absolutely massive and, I think, a great cause for optimism. By changing just this one aspect of our lives (though it won’t be easy) we could do so much!

Annual emissions and projected atmospheric concentrations of GHGs under Business as Usual (red) and with a 15-year phaseout of animal agriculture (green). Source

The researchers also broke down emissions and impacts of specific animal products and categories. The main takeaway from this is that a completely plant-based diet (a vegan diet) is not necessary to achieve massive reductions in emissions. A diet without red meat has almost just as much of a positive impact as a full vegan diet! Ruminants (cattle, buffalo, sheep, and goats) make up 90% of the projected annualized CO2 emissions through 2100. Therefore, just by replacing ruminants we can achieve 90% of the benefit of phasing out animal agriculture. That means you can still eat chicken and eggs, which are some of the “most efficient animal products on a per protein basis,” as they have per protein emissions 25 times less than that of ruminant meat. The bottom line: you don’t have to give up everything animal-based! 

I’ve broken down the main takeaways from this model, but there are many more details that I haven’t included. To read the full publication in PLoS Climate go here

Many other studies have similar findings. In the 2022 report, the Intergovernmental Panel on Climate Change (IPCC) listed a move toward plant-based diets as holding great potential for reducing emissions. A 2020 study in Nature Sustainability found that “shifts in global food production to plant-based diets by 2050 could lead to sequestration of 332–547 GtCO2, equivalent to 99–163% of the CO2 emissions budget” which would drastically improve the chances of limiting global warming to 1.5 °C. Data from Our World In Data (see graphic) reveals that less meat still has a lower impact than sustainably produced meat. More and more across the board, the findings are reaching the same conclusion: plant-based diets could seriously curtail global emissions. 


Last week I spent some time discussing the water footprint of various food products. What I found from my research is that animal products (especially meat) have higher water footprints than plant-based products. And, as you can guess, by moving toward plant-based diets there is great potential to save water, which is becoming an increasingly precious (and always essential) resource. 

A 2016 study in Science of the Total Environment found that a vegetarian diet leads to water footprint reductions of 30-53%. Another study in Water Resources and Industry determined that agriculture makes up 92% of the freshwater footprint of humans and almost one-third of this footprint comes directly from or relates to animal products. By moving away from animal agriculture, humans themselves would have much greater access to water. Addressing clean water access is majorly important; in 2019 the World Health Organization reported that 1 in 3 people did not have access to clean drinking water. 

Other Environmental Impacts

Animal agriculture is a major contributor to deforestation. Recall that 35% of the earth’s habitable land is used for animal agriculture (grazing and land used for animal food production). A landmark 2019 study published in Science by Joseph Poore and Thomas Nemecek revealed that a move to plant-based diets could lower the amount of land used for food by 3.1 billion hectares, which is a 76% reduction. 

Pollution and Environmental Racism 

Pollution is another place where the plant-based diet could help. Agriculture is one of the top sources of air pollution in the U.S. This is an issue for the environment because harmful gases like methane, ammonia, and hydrogen sulfide are released into the atmosphere from farms (mostly from Concentrated Animal Feeding Operations, or CAFOs). However, this is also a major human health issue. A 2021 PNAS study, which estimated the health impacts of air quality, found that “80% of the 15,900 annual deaths that result from food-related fine particulate matter (PM 2.5) pollution are attributable to animal-based foods.” That’s 12,720 deaths. The Washington Post ran an article specifically about this, with a focus on North Carolina, the state with the fourth most CAFOs in the U.S.

As The Washington Post explains, “the most insidious kinds of air pollution are known as particulate matter (PM) 2.5—tiny particles one-thirtieth the width of a human hair, which can become lodged in lungs or absorbed into the bloodstream. Exposure to PM 2.5 can lead to asthma and other breathing problems, and over the long term increases the risk of dying of heart disease, cancer, and stroke.” 

Waste from CAFOs is often put in spray fields around the farm. And the waste doesn’t stay there; it seeps into the surrounding environment in various ways (air pollution, run off, etc.). Source: 2013 Donn Young Photography 

And air pollution is not the only impact of CAFOs. The National Association of Local Boards of Health identifies nine environmental health effects of CAFOs including: groundwater, surface water, air quality, greenhouse gases and climate, odors, insect vectors, pathogens, antibiotics, and other effects (property values). 

But returning to CAFO-caused pollution, another issue emerges: environmental racism. In 2019 I did a research project called “CAFOs and the Poverty Position: Understanding the Impacts of CAFOs on Human Well-being.” What my research revealed was that U.S. counties with large concentrations of CAFOs had a great poverty level and a larger Black population. For my research, I largely focused on North Carolina, because at the time it had the greatest number of CAFOs in the U.S. Here’s one snippet from my research that reveals the CAFOs as a site of environmental injustice and racism:

The two North Carolina counties with the most CAFOs, Duplin County and Sampson County had 300 and 296 CAFOs, respectively. These two counties also have high poverty levels in comparison to surrounding areas (Duplin with 24.3% and Sampson with 26.3%). Alternatively, Wake County is one of two counties in the state with a poverty percentage below 12%. Its CAFOs count is 0. 

Beyond poverty, Duplin, Sampson, Wayne, and Bladen County, which have some of the state’s highest CAFO numbers, also hold the highest Black populations in the state. It’s no coincidence that the areas with the greatest numbers of CAFOs in the state are part of the Black Belt, a band of the south where large populations of slaves once worked on plantations. The impacts of this still reverberate.

“A century later, [B]lack residents of this region still experience high rates of poverty, poor health care, low educational attainment, unemployment and substandard housing,” says Nicole Wendee, science writer and researcher. Due to the clustering of CAFOs in poverty-stricken minority communities and their health effects, both environmental injustice and racism concerns have been raised for this region.

In the context of this blog, by moving to a plant-based diet we can reduce the demand for CAFOs and help reduce negative impacts on human health and cases of environmental racism.

A North Carolina home next to a CAFO. Source: 2013 Donn Young Photography 

Human Health

It is well-known that one’s diet is strongly linked to one’s health. There are many health benefits to be gained from a plant-based diet. To briefly summarize, “Studies ha[ve] shown that people following vegetarian and near-vegetarian diets have significantly lower prevalence of obesity, type 2 diabetes, heart disease, hypertension, cancer, and gallbladder disease, compared with non-vegetarians. In clinical trials, low-fat plant-based diets reduce body weight and blood pressure, and improve plasma lipid concentrations and glycemic control.” 

On the topic of cancer, there are strong links between a vegetarian diet and decreased risk. In 2015, the World Health Organization categorized red meat as possibly carcinogenic to humans and processed meats (bacon, sausage, jerky, ham, etc.) as carcinogenic to humans. The epidemiological studies used as the basis for the categorization established a strong link between the consumption of processed meat and colorectal cancer. There were also links, though not as strong, between processed meat consumption and stomach cancer. In terms of the risk of eating processed meat, according to WHO, “an analysis of data from 10 studies estimated that every 50 gram portion of processed meat eaten daily increases the risk of colorectal cancer by about 18%.” Red meat was also linked to colorectal cancer and showed possible links to pancreatic and prostate cancer, too.

Cancer is not the only thing the plant-based diet can help protect you from. A plant-based diet can reduce your risk of heart disease, which is caused by the buildup of plaque from cholesterol. The staples of an animal-based diet—meat, dairy, and eggs—are naturally high in saturated fat and cholesterol. A 2019 study that followed over 400,000 participants for almost 13 years concluded that consuming red and processed meat increases one’s risk of heart disease for every 100 grams eaten. A 2021 study in Cardiovascular Research determined, “the evidence is highly concordant in showing that, for the healthy adult population, low consumption of salt and foods of animal origin, and increased intake of plant-based foods—whole grains, fruits, vegetables, legumes, and nuts—are linked with reduced atherosclerosis [a form of cardiovascular disease] risk. The same applies for the replacement of butter and other animal/tropical fats with olive oil and other unsaturated-fat-rich oil.” 

It’s also been concluded by multiple studies that a plant-based diet can lower one’s chances of hypertension (this is mostly because plants have a lot of potassium, which lowers blood pressure). In terms of mental health, there is evidence suggesting that plant-based diets can reduce depression and anxiety. 

Many of the links between a diet of animal-products and poor health outcomes are newly established and still being studied. However, more and more research is reaching the same conclusion: a plant-based diet is one of the best interventions for improving health. Though, moving to a plant-based diet does mean you need to be aware of your intake of some vital nutrients that aren’t as prevalent or easily absorbed in plant-based products—but we’ll discuss this next week! This short section is by no means an exhaustive list of the health impacts of one’s diet so I would highly recommend checking out the health topics page on Forks Over Knives if you are curious about more of the diseases and health conditions that a plant-based diet can help combat!

Animal Well-being 

Content warning: graphic language

One last thing worth mentioning is how animals in CAFOs are treated. The only law protecting farmed animals is the Humane Slaughter Act, which was passed in 1958. According to US Legal under this act, “the slaughtering of livestock and the handling of livestock in connection with slaughter must be carried out only by humane methods.” Humane methods include: 

  1. “In the case of cattle, calves, horses, mules, sheep, swine, and other livestock, all animals are rendered insensible to pain by a single blow or gunshot or an electrical, chemical or other means that is rapid and effective, before being shackled, hoisted, thrown, cast, or cut; or
  2. by slaughtering in accordance with the ritual requirements of the Jewish faith or any other religious faith that prescribes a method of slaughter whereby the animal suffers loss of consciousness by anemia of the brain caused by the simultaneous and instantaneous severance of the carotid arteries with a sharp instrument and handling in connection with such slaughtering.”
Pigs kept in close confinement at a CAFO in North Carolina. Source: 2013 Donn Young Photography 

But this law concerns only the slaughtering. It says nothing about how the animals are kept between their arrival to the facility and their slaughter. And it’s no secret that conditions for the animals are abysmal. Animals are kept in dark, small spaces for long periods of time. Pigs are often kept in gestation crates during pregnancy and egg-laying hens are often kept in cages that prevent them from even turning around. There are many other inhumane methods used across large-scale farms, and this is not an animal rights blog, so I’ll let you defer to PETA for that.


There are many reasons to consider a plant-based diet, whether it’s for environmental reasons, human health and well-being, or animal rights. Everyone has their own perspective and experiences to consider as they make their personal choice. Regardless, I hope I’ve inspired some of you to consider a more sustainable alternative (across many fronts) to an animal-based diet. When considering a decision like this, remember to take it one bite at a time! 

Stay tuned to hear about how to actually go about reducing your consumption of animal-products and moving to a plant-based diet with practical tips and resources, along with my own experience!

Thanks for reading!


Recipe of the week: Ratatouille!

This week I am deferring to Tasty for another one of my favorite meals. Ratatouille is a purely vegetable-based dish originating in France. It typically consists of tomato, bell pepper, onion, zucchini, squash, and eggplant with a few spices and herbs like garlic, thyme, and basil. In this recipe, the vegetables are sliced with a mandolin or knife, which is relatively labor intensive and time-consuming, but entirely worth it! (To save time you can also buy pre-sliced veggies for a bit more money, if desired). There are many ways to prepare this dish but this specific recipe is wonderfully flavorful! Check out the recipe here. Thanks, Tasty!

P.S. This meal is best when paired with a viewing of the movie Ratatouille. My sister and I like to celebrate New Year’s in this very way—spending time together slicing the veggies and carefully ordering them in a circular dish. Then we sit down with our bowls and have ratatouille with Ratatouille