Moo-ve Over Cows: the Environmental Footprint of Milk Alternatives

Over the years, I have sampled a plethora of dairy milk and milk alternatives. Suffice to say, the path to choosing the perfect milk can become a rabbit hole. I often find myself standing in the mountains and valleys of the grocery store aisles, overwhelmed by the cow, cashew, and coconut milks before me.

Infants rely on milk to gain the necessary nutrients to grow and develop properly. After infancy, children begin developing lactose malabsorption, where digesting lactose becomes difficult. 68% of the human population experiences lactose malabsorption. At this stage, most mammals stop drinking milk and graduate to solid foods. However, humans have combated lactose intolerance through genetic mutations and diverse gut microbiomes. They adopted the strange practice of drinking milk from other animals and have carried it through generations. Archaeological and biogeochemical evidence suggests that humans began using animal milk to diversify their diets. Pastoralist nomad communities ate dairy products to supplement their diets as they ventured through extensive stretches of grass, relying on their sheep and goats to eat grass and turn it into consumable products for humans. This practice has persisted in modern society, with nutritional guides encouraging children and adults to consume dairy products daily and roughly six billion people incorporating it into their diets.

Communities love milk for its nutritional value, accessibility, and versatility. In a healthy diet, dairy milk is an exceptional source of calcium, protein, vitamin B2, vitamin B12, potassium, and phosphorus. As a $753 billion U.S. industry, dairy is widely available in grocery stores. It is a convenient and familiar drink that is accessible to most families with its high demand. As an ingredient, milk is critical for many breakfast battered dishes, soups, pasta, desserts, and specialty beverages. Milk has become an integral part of homes, the culinary sphere, and the economy.

With the majority of the world’s population experiencing lactose malabsorption and its adverse effects, milk alternatives have quickly gained popularity. Grocery stores often carry lactose-free, soy, oat, almond, cashew, rice, and coconut milk in addition to the popular animal milk. For those with nut or soy allergies, some of these alternatives must be eliminated from consideration. To compare the values of milk options, many individuals inspect their ability to compete with the nutritional value, accessibility, and versatility of animal milk. For example, soy milk has one of the highest protein content in milk alternatives, with 0.79 g of protein per ounce compared to whole milk with 0.96 g per ounce. Oat and unsweetened almond milk have significantly smaller protein contents, only carrying 0.38 g and 0.18 g of protein per ounce, respectively. Access to certain milk alternatives differs based on the prices and distribution of each product. Macadamia, hemp, and pea milk are exceptionally nutritious milk alternatives but are less accessible in rural regions of the United States. Soy milk and almond milk are 2.5 times more expensive than cow milk, being sold at $1.60 per 8 ounces compared to cow milk at $0.64 for the same amount. Soy and oat milk are popular milk alternatives for baking because of their texture and sweetness, but oat milk is 4 times more expensive than cow milk, costing $2.56 per 8 ounces. These calculations are important factors in determining the best milk alternative for each person, but one integral element must be considered: the environmental impact of each creamy beverage.

Cow milk, the popular choice for many families in the United States, must go through lengthy steps to upgrade the milk from a cow’s udder into an utterly delectable beverage. There are 278 million dairy cows worldwide, and unfortunately their environmental impact is far from appetizing. Cows are fed 100 pounds of grains, silage, hay, and leftover crops daily, requiring 31.4 million acres of land to grow the feed. Cows produce 17 gallons of manure and urine daily, emitting greenhouse gases and polluting the nearby water and air. The cows are regularly milked, and the raw beverage is cooled, stored, and transported by trucks to processing plants. The milk undergoes standardization, pasteurization, and homogenization before being packaged and transported to suppliers. Processing, packaging, refrigeration, and transportation all produce greenhouse gas emissions that contribute to the climate crisis. Additionally, throughout the milk production process, 144 gallons of water are used to produce one singular gallon of milk. This is equivalent to buying a one-gallon jug of milk and running the bath to waste three full tubs of water. Every aspect of milk production is environmentally destructive, from feeding the cows and letting them pollute the atmosphere with methane, to producing greenhouse gases in the processing plants and tailpipe emissions while transporting the beverage.

Agroecology and environmental experts Poore and Nemecek conducted a study researching the environmental impacts of the global food industry, which creates around 13.7 billion metric tons of carbon dioxide equivalents. The food supply chain also wreaks catastrophic acidification and eutrophication, destroying ecosystems and disrupting biodiversity in nature. Poore and Nemecek collected data for various environmental impact indicators, most notably land use, greenhouse gas emissions, freshwater use, and eutrophication. Analysis of their research illuminates the footprints of dairy, oat, soy, almond, and rice milk in these four arenas.

As depicted, dairy milk causes the most pronounced environmental damage in all four sectors, leading to land usage, greenhouse gas emissions, freshwater use, and eutrophication by a landslide. The agricultural land needed for dairy milk is over 11.5 times greater than its closest competitor, requiring almost 9 square meters per liter of milk. The other milk alternatives each require less than a square meter per liter. The evidence is clear: any of these milk alternatives are viable replacements for dairy milk and will save the planet from water scarcity, greenhouse gas emissions, eutrophication, and excessive land usage.

Comparing the milk alternatives proves to be more complicated. Rice milk requires the least land but produces the second most greenhouse gas emissions and eutrophication. Almond milk produces the least amount of greenhouse gases but uses 371.46 liters of water to create one liter of milk, following dairy milk in second place for freshwater usage. Oat milk is not significant in any category, consistently ranking in the middle to low ends of the spectra. Soy milk requires the least freshwater at 27.8 liters per liter, over 22 times less than dairy milk and over 13 times less than almond milk. Additionally, it ranks as the milk alternative with the lowest amount of eutrophying emissions, producing 1.06 g of runoff per liter compared to 10.65 g from dairy milk and 4.69 g from rice milk.

With these considerations in mind, I would advise individuals to opt for soy milk as their preferred milk alternative. It has the least significant freshwater usage and eutrophication impact, while also ranking comparably to the other milk alternatives’ greenhouse gas emissions and land usage. Soy milk maintains land usage over 13 times smaller, and greenhouse gas emissions over 3 times lower than those of dairy milk. Additionally, it is often a preferable choice for individuals with nut allergies, lactose intolerance, and a desire to maintain high protein and low cholesterol intake. Furthermore, it is a popular alternative to milk in recipes because of its neutral taste and viscosity that provides structure to baked goods.

Soy milk is sometimes condemned for its contribution to the deforestation of the Amazon region but this rhetoric should be dismissed because it does not encapsulate the entire story. While soy is a significant reason for Brazilian land clearing and replacement, soy milk is not the motive. The deforestation is driven by the demand for soy as an animal feed crop. Over 75% of global soy production is utilized for animal feed, a statistic that rises to 95% for the Amazon region. To truly deter soy production from the deforestation of diverse lands, the demand for animal meat and animal products must decrease.

To create a more sustainable and environmentally-conscious dairy milk industry, Poore and Nemecek suggest following the mitigation framework they designed. Cow farmers and milk producers must first accurately monitor and record their footprints, which policy-makers will analyze and subsequently create more sustainable targets. These targets will be incentivized with tax breaks or reallocated subsidies. Milk producers will adopt sustainable practices and communicate their developments to consumers, who will continue to incentivize and demand environmentally conscious advancements.

While sustainable practices begin to develop within the dairy milk industry, consumers can continue to choose less environmentally harmful milk alternatives to incentivize sustainable practices. This analysis and decision-making methodology can be applied to any food category, from selecting the most optimal fruit to pondering the best tortilla chip. Consumers can weigh the environmental impact indicators for the various products on the shelves while learning about the intriguing food industry. With intentionality and advocacy, global consumers who were once trampled into rabbit holes can gain control of their diets and create a sustainable revolution within the food supply chain.

 

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