Evaluating the Environmental Impact of Plant-Based Milks vs. Dairy

The shift in consumer preferences from dairy to plant-based milks, such as oat, almond, and soy, reflects a growing awareness of environmental sustainability. This trend has led to increased consumption of plant-based options since 2018-19. However, the environmental benefits of these alternatives compared to traditional dairy milk are complex and multifaceted. Dr. Michalis Hadjikakou, a researcher at Deakin University, emphasizes the importance of context in choosing milk, noting that factors like nutritional needs and environmental impacts must be considered.

The Guardian

Research indicates that plant-based milks generally have lower greenhouse gas emissions compared to dairy. The World Resources Institute reports that dairy milk emits approximately 330 grams of CO2 per cup, while soy, oat, and almond milks emit 122g, 102g, and 98g respectively. Fraser Taylor, managing director of FoodSwitch, highlights that plant-based milks have a better environmental footprint, particularly concerning greenhouse gas emissions.

The Guardian

Water consumption varies significantly among different milk types. Oat milk is noted for its low water footprint, as oats are typically grown in dryland conditions with minimal irrigation. In contrast, almond milk has the highest water usage, requiring a Mediterranean climate and substantial irrigation. Soy milk's water use is contingent on farming practices and regional water availability. Hadjikakou points out that while dairy's water use can also vary, it generally falls between that of oat and almond milks.

The Guardian

The environmental impact of processing and packaging is another critical factor. Some studies suggest that these stages can account for up to 79% of the environmental impact of plant-based milks, compared to only 4% for cow's milk. Despite this, plant-based milks still produce about 1kg of CO2 per liter, significantly less than the 3kg produced by dairy.

The Guardian

Fertilizer application is essential for crop yield and soil health. Hadjikakou notes that soybeans, as legumes, can improve soil nitrogen levels, making them advantageous in this regard. In contrast, dairy farming in Victoria has seen a reduction in fertilizer use, but it still remains higher than that of oat crops. Almonds require more fertilizer, complicating their environmental assessment.

The Guardian

Ultimately, there is no definitive "best" option among milk types; each has strengths and weaknesses depending on various factors. Hadjikakou suggests a mixed approach to milk consumption, recommending that consumers use different types based on their specific needs—such as almond milk in lattes and dairy milk for cereal—to minimize overall emissions.

The Guardian

• “Plant-based milks still definitely do have a better environmental footprint than dairy milks, particularly on greenhouse gas emissions,” — Fraser Taylor, Managing Director, FoodSwitch

The Guardian

• “They each do pretty well at different things.” — Dr. Michalis Hadjikakou, Deakin University

The Guardian

While the environmental impacts of plant-based milks are generally viewed as favorable compared to dairy, discrepancies exist regarding the exact figures for water usage and emissions, highlighting the need for more comprehensive data on oat and almond milks.

The Guardian