Sure, we all love eggs and dairy. We use them to create breakfast scrambles, melt-in-your-mouth mac and cheese, and some of the best best charcuterie boards around. But while they're undeniably delicious, their impact on the environment isn't so pretty. Here's everything you need to know about the environmental impact of eggs and dairy.
What Exactly Is Dairy?
Dairy is defined as “food produced from the milk of mammals,” so eggs are technically not part of the club. Oddly enough, many people continue to group the two together. So that’s what we’ll do in this article: after all, a little inclusivity never hurt anyone.
But is dairy bad for the environment? The short answer is often yes, but the complexities behind this answer are revealed as we explore more of the specifics. The dairy industry is responsible for 2% of the total U.S. greenhouse gas emissions. On top of that, 144 gallons of water are needed in the U.S. to produce 1 gallon of milk.
Globally, there are around 270 million dairy cows used to make milk. These animals not only contribute to increasing greenhouse gas emissions, but also the resources used to raise them add manure and fertilizer to our water bodies, and land conversion fuels the loss of crucial ecosystems. All in all, the production of dairy facilitates climate change with its release of gases like methane and carbon dioxide.
How Do Dairy Products Affect the Environment?
Emissions from the dairy industry stem from feeding processes, manure, and enteric fermentation (which essentially refers to the animal’s digestion). One particularly tragic incident caused by manure disposal occurred in 2010 when "15 million gallons of manure, water, and [more]" went into a Washington state river.
But the problems with dairy products don’t stop there. Ammonia emissions leak from dairy farms and can lead to air contamination; as touched upon earlier, manure, and fertilizer runoff affect marine ecosystems. This is because increased concentrations of fertilizer nutrients like nitrogen and phosphorous in water runoff lead to an increase in algae growth. More algae on the water's surface decrease the oxygen available for the marine organisms in the water body to use. This is called eutrophication, which is also known as nutrient pollution.
In addition to the effects mentioned above, dairy also plays a role in decaying soil health through potential overgrazing. Well-managed manure and grazing are necessary for healthy soil and the protection of land. If livestock are not properly rotated across the land, the animals will graze on the same plots, which can degrade the land. In extreme cases, desertification can occur when the land plot suffers at least a 10 percent loss in productivity.
Dairy production presents a risk for habitat loss through its surprising link to deforestation. Put simply, soybeans are large contributors to deforestation, and dairy cows eat soy. It is important to keep dairy-producing animals happy and healthy, but it is also important to understand their impact on land and the natural environment, so be sure to check the labels on your dairy products before purchasing them.
Specific dairy products have different impacts on the environment. With regards to the impact of different types of milk, dairy and non-dairy, (which you can learn about here), a good rule of thumb is to buy skim or low-fat milk rather than whole milk. As for cheese and eggs, consumers' decisions are less clear-cut.
Cheeses have a very high carbon footprint. According to researchers from the University of Wisconsin-Madison, more than 90 percent of the greenhouse gas emissions cheese emits comes from the milk production stage. The study concluded that lower-fat cheeses, such as cottage cheese or skim mozzarella, take less milk to produce, and thus are better for the environment.
Unfortunately, there is limited research into the environmental impact of hard cheeses as opposed to soft cheeses or fresh cheeses. This availability gap parallels the room for further research comparing the environmental impact of milk and dark chocolates. For a visual representation of all the energy and steps taken in the cheese-making process, see the diagram below.
Hard cheeses like cheddar require more milk to produce than soft cheese, like mozzarella. Many people prefer hard cheese because of its reduced lactose content that occurs as a result of bacteria breaking down its milk content across the aging period.
Researchers also stated that the longer a cheese is left to age, the more energy it takes to produce. This is because hard cheeses require steady aging temperatures, asserting that they are more intensive for the environment. A cheese's transportation time and amount of water needed to produce it also make a difference in its carbon footprint. So buy local if you can.
Eggs (of All Colors)
Interestingly, the color of eggs vary depending on the breed of the chicken that produced them (some are even blue or blue-green). This being said, the “environment, diet, and level of stress may also affect shell color.”
Brown eggs do tend to be more expensive in stores, however, since they are often associated with the organic or free-range label. In fact, a good way to reduce the carbon footprint of your eggs is to actually seek out organic or other ethically-labeled eggs like these:
If you consume dairy, these environmental impact descriptions should be a reason to stay informed rather than worry. Like many food solutions, some may opt to consume these products in moderation. Another option is to find vegan alternatives for dairy products, but it is important to do your research into the dietary and environmental implications if you wish to make the switch.
To elaborate on informed consumerism, use a few of the topics discussed in this article to help you better understand what you are eating and how it impacts the planet. Look for product labels, such as USDA Organic, on your dairy products and buy local when you can. Let’s encourage better dairy farming practices to help our bodies and our Earth.