In 2006, a United Nations report warned that rearing cattle generated more greenhouse gases than driving cars. So, is your rib-eye steak more destructive to the planet than your Honda Accord? Animal agriculture and meat consumption are big contributors to global warming. But is a plant-based diet the answer?
The skeptics among us: are greenhouse gases REALLY heating the planet?
Any discussion about saving the planet has to address how we know that the planet actually needs to be saved. Skepticism in science is healthy, and reflects an open-minded desire to understand all of the facts before drawing a conclusion. But skeptical beliefs on this topic are dangerous. We know too much and inaction is too risky.
While some may state that global warming is based on theory and models, it is actually based on data. Surface temperature stations and satellites measure the Earth’s surface and lower atmosphere. There are also tools that measure the warming of the Earth’s oceans. Tracking data show that the sea ice, glaciers, and ice sheets are all receding, and that ocean temperatures are on the rise.
Climate change skeptics may jump in here and say, so what? The Earth’s climate has changed before. How do we know that human contributions are responsible for warming the planet? As explained by Skeptical Science, a not-for-profit science education site, satellite data provide information on how much energy is arriving from the sun, and how much is leaving the earth. An increasing amount of greenhouse gases (particularly CO2 from burning fossil fuels such as oil and gas) in the atmosphere is keeping energy trapped and warming the earth. The consequences of this include more extreme weather patterns, more acidic oceans, higher sea levels, higher wildlife extinction rates, dirtier air, and challenges with the food supply.
What does this have to do with my rib-eye?
Even though fossil fuel combustion is the number one contributor to greenhouse gas emissions, animal agriculture also plays a significant and critical role. Deforestation and land used to grow feed crops, as well as associated animal waste products, all are contributing to the rise in CO2, methane, and nitrous oxide gases in the atmosphere. Producing beef requires more resources than other sources of meat, and rearing cattle produces more methane than other farm-raised animals.
So, if I become vegetarian or vegan will the future be saved?
The environmental costs per unit of livestock production must be cut by one half, just to avoid the level of damage worsening beyond its present level.
–The United Nations Food and Agriculture Organization’s Livestock’s Long Shadow report
As you might know, I haven’t eaten meat for 25 years. I had no clue at the time that this choice had anything to do with the environment or somehow would minimize my “food print.” I mention this to reveal my bias.
Studies show that a vegetarian diet and, more significantly, a vegan diet have the least amount of impact on the environment when compared with diets incorporating animal products. A global switch, according to one study, to diets that rely less on meat and more on fruit and vegetables could reduce the related greenhouse gas emissions up to nearly two thirds. According to Harvard Medical School, however, only 8-10 million Americans are vegetarian, and about two million are vegan. Realistically speaking, it is highly unlikely to get global participation in that type of diet change, and in the United States, reshaping perspectives on food still needs significant investment.
Should you become a vegetarian or a vegan? I’m not one to tell people what to do. But based on research, a predominately plant-based diet is better for your health and the environment. If you really want to reduce your greenhouse gas emissions foot print through your personal choices, you would have to also sell your car, stop taking airplanes, and have no or fewer children. You could start by looking at your own food choices though and consider cutting out beef. And, hey, as Whitney Houston once said, children are our future, so you may want to rethink that rib-eye.
Like everything else on this blog, don’t forget to examine the broader constructs and systems within which we live too. More on food systems and food policy soon!
Resources
- If you or someone you know is still not convinced about climate change, explore NASA and Skeptical Science’s websites to more deeply understand the evidence.
Articles - Diet and the environment: does what you eat matter?
- Environmental impact of omnivorous, ovo-lacto-vegetarian, and vegan diet
- Improving diet sustainability through evolution of food choices: review of epidemiological studies on the environmental impact of diets
- Quantification of the environmental impact of different dietary protein choices