- Environmental Impact of Soy Milk
- Environmental Impact of Almond Milk
- The Vegan Dilemma
- Which Is Better, Soy or Almond Milk?
The ubiquity of plant-based milk continues to rise, with researchers expecting its market size to almost double from $22.6 billion in 2020 to $40.6 billion by 2026.
The trend emerged in the ’90s with the original superstar of milk alternatives, soy milk, and has since grown into a diverse category now including everything from rice, hemp, and coconut to oat milk. Today, the fastest-growing subsector is unequivocally almond milk.
So, which is better for the environment, the initiator or its prominent outpacer?
It’s a complicated question that spans a plethora of issues, from deforestation to greenhouse gas emissions, from water use to food waste. Factor in the chemicals used to grow the different crops, not to mention where those crops come from, and the world of “alt milk” can seem like an impossible minefield of unsustainable practices.
Not to worry: Vegan milk is still three times better for the planet than dairy milk based on emissions alone. Here’s a breakdown of the environmental impact of almond milk versus soy milk so you can make an informed decision.
Environmental Impact of Soy Milk
Although soy milk was the first major alternative on the scene back in the ’90s, a 2018 Mintel report revealed that it now accounts for only a 13% share of the plant-based milk market.
Soy milk is made by dehulling soybeans using steam, then cooking them, grinding them into a hot slurry, filtering the mixture, and, finally, blending the milk with sugar and any other flavorings to make it more palatable.
Here’s how soy milk impacts the environment, from planting the beans to shipping the finished product.
Water Use
Soybeans require a third of the water needed to feed cows for dairy milk. The crop itself consumes 15 to 25-plus inches of H2O per year. Of course, water is also incorporated at the final stages of manufacturing and needed to make additional ingredients and materials like cane sugar, vanilla flavoring, and cardboard packaging. In total, a single liter of the final product reportedly takes 297 liters of water to produce.
In other words, the crop water use efficiency of soybeans is comparable to that of maize (corn), field peas, and chickpeas.
In agriculture, total water use is separated into three categories: green (rainwater), blue (surface and ground water), and grey (fresh water used to assimilate pollutants). Soy crops use different amounts of water and different types of water depending on where they’re grown. For instance, although a rainfed soy crop in Canada requires almost 40% more water than an irrigated soy crop in France, the Canada crop could be seen as more sustainable because it uses only green water.
Land Use
For years, the U.S. (Midwest) was the world’s leading soy producer, but Brazil took over the top spot in 2020—and it’s expected to retain that position. Brazil-grown soy was linked to 200 square miles of deforestation in 2018 alone, and the country’s production has increased by about 11% since then.
Greenhouse Gas Emissions
Emissions from soybean production depend largely on where the soy is grown. In the U.S., soybean production reportedly emitted 7.9 pounds CO2-equivalent gas per bushel in 2020, down from 13.6 pounds per bushel in 1980.
The emissions from Brazil-grown soy, on the other hand, vary drastically. A 2020 report revealed that CO2 emissions from soy production and export was “more than 200 times higher” in some Brazilian municipalities than others.
Emissions, the study pointed out, mostly come from “the conversion of woody vegetation into cropland”—in other words, cutting down carbon-absorbing trees for cropland. But they also come from harvesting, manufacturing, and shipping.
On average, a cup of soy milk creates about half a pound of carbon dioxide.
Pesticides and Fertilizers
Pesticide and fertilizer use is rampant in non-organic soy farming. The USDA says 44% of (domestic) planted acres are treated with at least one of the four most widely used fertilizers—nitrogen, phosphate, potash, and sulfur—and an astounding 98% of planted crops are treated with herbicides. Fungicides are applied to 22% of planted acres and insecticides to 20%.
Studies have shown that the most common active ingredient in herbicides, glyphosate potassium salt, can leach and run off into groundwater and surface water despite its ability to quickly degrade. When herbicides reach groundwater, they can threaten crop health and indirectly harm wildlife by ravaging their food sources and habitats.
Environmental Impact of Almond Milk
Whereas soy milk accounts for only 13% of the plant-based milk market share, newcomer almond milk accounts for a whopping 64%, making it the most popular alt milk variety.
Just because it’s popular, though, doesn’t mean it’s the most eco-friendly option. In fact, almond milk has drawn immense criticism for its environmental impact—namely the tremendous amount of water almond trees need and the pressure they put on commercial bees.
Here are the ways almond milk affects the environment.
The biggest criticism of almond milk is its water footprint. A single almond drinks more than three gallons of water over its lifetime.
What’s worse about almond trees’ water use efficiency is that the crops grow almost solely in the water-stressed region of central California. Indeed, 80% of the world’s almonds are grown in the perpetually droughty Golden State, and they guzzle up 9% of the entire state’s water supply every year. The Almond Board of California argues that 9% is “less than their proportionate share” considering almonds make up about 13% of the state’s total irrigated farmland.
Because some regions of the agri-popular Central Valley get as little as five inches of rain per year, the vast majority of water used by almond growers is “blue” water—it comes from finite groundwater reservoirs. Depletion of these underground aquifers has caused the ground to sink a total of 28 feet over the past century.
Though almonds are not native to California, the state dedicates over 1.6 million acres—or about 13%—of its irrigated farmland to this lucrative crop. Almonds are California’s largest agricultural export.
The trees live for 25 years and must be cared for year-round, whereas other crops are slashed and rotated to keep the soil healthy. Their constant need for care perpetuates the water crisis because farmers can’t allow their crops to go dormant during particularly dry seasons without killing them. Instead, they must resort to using groundwater to avoid economic catastrophe.
What’s more, this kind of monocropping allows pests to feast permanently on the almond trees knowing they won’t be chased away seasonally. And almond trees, as it turns out, are a favorite among peach twig borers.
What it lacks in water use efficiency and land advantages, almond milk makes up for in its carbon footprint. It has the lowest greenhouse gas emissions of any milk type because almonds grow on trees, and trees absorb CO2. One cup of almond milk reportedly emits about a third of a pound of the greenhouse gas.
But that’s just its embodied carbon—i.e., the carbon emitted during the process of growing and making almond milk. Because almonds grow only in a very specific environment, mostly in California, they must be shipped from the U.S. West Coast all around the world, consequentially increasing almond milk’s carbon footprint.
Almond growers rely on chemicals to deter pests like the peach twig borer. According to the California Department of Pesticide Regulation’s 2018 Annual Statewide Pesticide Use Report, more than 450 chemicals were used on almond crops. A handful of them were petroleum distillates.
Because almonds grow on deciduous trees, they also need constant nitrogen replenishment, which they get from synthetic fertilizers.
The crop’s chemical dependence puts vulnerable bees at risk—1.6 million colonies of which are brought to the Central Valley annually to pollinate almond trees. Over the years, 9% of bee colony loss has been attributed to bee-toxic pesticide use. Ironically, a decline in healthy commercial beehives could effectively wipe California’s almond crops out.
The Vegan Dilemma
Although both soy and almond milk are technically vegan—meaning neither contains animal-derived ingredients—their respective negative impacts on animal populations hit a nerve with many vegans.
Meanwhile, almond farming is one of the major causes of honey bee stress. The U.S.’s commercial honey bees are in peril because of parasites, disease, a lack of diverse pollen resources, and pesticide exposure, studies say. The almond pollination period requires them to wake from their winter dormancy two months early, creating an unnatural and unhealthy circumstance in which the bees must work year-round. This, combined with pesticide poisoning from almond crops, threatens already-vulnerable bee populations.
Which Is Better, Soy or Almond Milk?
Whereas soy can be grown almost anywhere, without the use of chemicals, and with little to no blue water, almonds must grow in hot, dry climates like California—and the California drought crisis is worsening. The California Department of Water Resources declared 2021 the second driest year on record.
Besides buying organic and ethically sourced soy (or, better yet, oat milk, which uses minimal water and land), you can reduce your impact by buying long-life milk that doesn’t require refrigeration and, when possible, making your own plant-based milk at home to avoid preservatives and packaging.
