by Linda Illingworth, RDN

As a Registered Dietitian, I’m often asked whether plant-based milks or cow’s milk are better for health and the environment. It’s an important conversation, especially as dietary choices increasingly intersect with personal health goals and environmental sustainability. Let’s take a look at the strengths and weaknesses of three popular options: oat milk, almond milk, and cow’s milk.

Health Benefits

Cow’s Milk

Cow’s milk is a nutrient-dense food that has been a dietary staple for centuries. It’s rich in high-quality protein, calcium, vitamin D (when fortified), and essential B vitamins, such as B12 and riboflavin. The protein in cow’s milk is complete, meaning it contains all nine essential amino acids required for muscle repair, immune function, and other bodily processes. One cup of cow’s milk provides 8 g of protein.

However, dairy products may not be suitable for everyone. People with lactose intolerance may struggle to digest lactose, the sugar in milk, leading to symptoms such as bloating and discomfort. Dairy proteins are also a common allergen. There are growing concerns about dairy allergies and the potential link between high dairy consumption and certain health conditions, such as acne, inflammation, and prostate issues.

Oat Milk

Oat milk has gained popularity for its creamy texture and versatility. It is naturally free of lactose, milk proteins, soy, and nuts. This makes it an excellent choice for those with food sensitivities. Oat milk is often fortified with calcium, vitamin D, and B12 to mimic the nutrient profile of cow’s milk.

In terms of nutrition, oat milk is lower in protein than cow’s milk with only 3 grams per cup, but provides beta-glucans, a type of soluble fiber that supports heart health by helping to lower cholesterol levels. Additionally, oat milk is naturally higher in carbohydrates. During processing, oats are soaked, blended, and strained, and enzymes are often added to break down oat starches into simple sugars. This process increases the carbohydrate content and enhances its natural sweetness. While this can help provide an energy boost, it may not suit people managing high blood sugar.

Almond Milk

Almond milk is a low-calorie, plant-based alternative popular among those seeking a lighter option. Like oat milk, it’s naturally lactose-free and often fortified with calcium, vitamin D, and B12. Almond milk is low in protein and low in carbohydrates, making it less satiating but a suitable choice for individuals on low-carb or calorie-restricted diets. Almond milk has only 1 gram protein per cup.

One notable downside is its relatively low nutrient density unless fortified, as almonds lose many nutrients during processing. No matter which milk you choose, a variety with no or minimal added sugar is key to maximizing health benefits.

The Environmental Impact
It’s important to note that statistics on environmental impact are extremely complex and the environmental impact of producing a food can vary widely between producers by as much as 50%.

Cow’s Milk

Producing cow’s milk has a significant environmental footprint. Dairy farming contributes to greenhouse gas emissions, water usage, and land consumption. Cows produce methane, a potent greenhouse gas, as part of their digestive process. Additionally, large-scale dairy farming can contribute to deforestation and water pollution from runoff of waste products. Producing a gallon of cow’s milk requires approximately 120 gallons of water.

Oat Milk

Oat milk has a lower environmental impact than cow’s milk and almond milk. Oats require less water to grow compared to almonds and produce fewer greenhouse gas emissions than dairy farming. On average, producing a gallon of oat milk requires about 48 gallons of water. They are also versatile and can be cultivated in various climates, further reducing their ecological footprint. For eco-conscious consumers, oat milk stands out as one of the most sustainable choices among plant-based options.

Almond Milk

Almond milk’s environmental impact is a mixed bag. While it has a smaller carbon footprint than cow’s milk, almond cultivation is extremely water-intensive, particularly in California, where most almonds are grown. Producing a gallon of almond milk requires approximately 192 gallons of water. This raises concerns about water scarcity in drought-prone regions. Additionally, almond farming has been linked to bee population declines due to pesticide use during pollination.

When choosing between oat, almond, and cow’s milk, consider both your nutritional needs and environmental values. Cow’s milk is nutrient-dense and protein-rich but comes with a high environmental cost. Oat milk is an excellent middle ground, offering health benefits such as heart-friendly beta-glucans while maintaining a relatively low ecological footprint. Almond milk is a low-calorie option with a smaller carbon footprint than dairy but raises sustainability concerns due to its water use.

Ultimately, the “best” choice depends on your individual priorities. Whether you’re motivated by health, taste, or environmental concerns, being informed empowers you to make decisions that align with your goals and values. As always, balance and moderation are key—and sometimes, diversifying your choices can be the best path to health.

For more information on the environmental impact of plant-based and dairy milks you may enjoy:
https://www.statista.com/chart/22659/cows-milk-plant-milk-sustainability/
https://www.nytimes.com/interactive/2022/dining/climate-change-food-eating-habits.html