There has been an upward trend of buying plant-based alternative milks due to lactose intolerance, milk allergies, and for sustainability reasons. A study by Journal of Food Science and Technology showed that cow milk has the most balanced amount of protein, fat and carbohydrates. However, a study by the University of Oxford reveals that dairy milk emits three times more greenhouse gases than non-dairy milks. So what is the best milk to drink nutritionally and environmentally? In this article, we will explore the differences in environmental impact and nutritional value of nine types of milk: soy, oat, almond, rice, hemp, macadamia, coconut, cashew, and pea milk.
Soy Milk
One of the first cow milk alternatives, soy milk probably has the closest, balanced nutrition to cow milk. It has the highest amount of protein per serving compared to other plant-based milks and contains isoflavones, a phytonutrient, which may have cancer-fighting properties.
According to researcher David Pimentel, approximately 0.195 kg of CO2 to produce a 200 mL glass of soy milk. Soybeans are also legumes, so they fix nitrogen in the soil and lower the amount of nitrogen fertilizers needed. A drawback of soy milk is the amount of land required to grow soybeans. Currently, the Amazon rainforest is being deforested to grow soybeans, which is detrimental to the environment.
Oat Milk
Oat milk is a good choice for people with allergies or intolerances since it does not contain lactose, nuts, and soy. Those with gluten allergies can purchase oat milk made from gluten-free oats. Oat milk has one of the highest calories, carbohydrates, and fiber among plant-based milk varieties. However, oat milk does not have much protein.
All around, oat milk has less of an environmental impact compared to most milk alternatives. For a 200 mL glass of oat milk, there is about 0.18 kg of CO2 emission, which is slightly more than almond milk but less than soy milk. In terms of water and land use, oat milk has a relatively low impact. The New York Times stated only one-sixth of water and resources needed to make one pound of almonds is needed to make one pound of almonds.
Almond Milk
Low in sugar, almond milk has one of the lowest calories. Almond milk also contains more unsaturated fats rather than saturated fats, which may help people lose weight. It is also naturally high in vitamin E, which may be beneficial to reduce inflammation and stress. Although it is low in calories, almond milk is low in protein and carbohydrates compared to alternatives.
Environmentally, almond milk requires more water to produce than soy or oat milk. A single glass of milk requires 130 pints of water, which is more water used than for a typical shower. Approximately 80% of the world’s almonds are grown in California, which is problematic since California is dry and susceptible to droughts. However, almond milk produces slightly less greenhouse gas emission: a 200 mL glass of almond milk makes about 0.14kg of CO2.
Rice Milk
Nutritionally, rice milk is fortified to become a good source of calcium, vitamin A, and vitamin D. Rice milk is also naturally sweeter than other alternatives. According to the U.S. Food and Drug Administration, only relying on rice milk can be a risk for infants and children because of inorganic arsenic levels.
Similar to almond milk, rice milk also requires a lot of water (54 liters per 200 mL glass of milk). However, unlike almonds, rice does not require as much land and has slightly higher greenhouse gas emissions (0.24 kg CO2 per 200 mL glass).
Hemp Milk
Hemp milk is made from the hemp plant, which contains a complete protein, healthy unsaturated fats, and minerals. Some benefits of hemp milk may include better skin health and protection against heart disease.
Hemp is a non-GMO plant and typically does not require chemicals to produce enough quantities of the plant. It also does not deplete nutrients from the soil. For water resources, hemp requires less than 1/3 of the water almonds need to grow.
Macadamia Milk
Similar to almond milk, macadamia milk is also usually low in calories, but the fat content is higher than some other milk alternatives. Macadamia milk also is low in protein. As a nut milk, it is not the best option for those with nut allergies.
Macadamia milk is a better alternative than almond milk in terms of water footprint. Macadamias usually grow in areas with fewer water shortages. However, with more climate change, water scarcity could increasingly become a problem for regions such as Hawaii or Australia, where macadamia nuts are produced.
Cashew Milk
Unlike cow’s milk, cashew milk has no naturally occurring sugars. Therefore, it will not suddenly increase your blood sugar. One cup of cashew milk contains 50% of your daily vitamin E, which may help protect your skin against sun damage. It also contains a good amount of vitamin K, which is vital for blood clotting.
Cashew crops have a low yield, so it requires more energy to grow the same amount as other plants or nuts. Therefore, cashew milk is not the most sustainable milk option. Additionally, cashews also require more water than other milk alternatives.
Coconut milk
Consuming moderate amounts of coconut milk may be able to lower cholesterol and promote weight loss. Coconut milk is high in saturated fat, which should be avoided to have a healthy diet.
Growing coconuts has a fairly low impact on land, and the use of water is relatively low. A drawback is that coconuts are typically grown abroad in tropical areas such as Indonesia and the Philippines, which requires transportation and emits more greenhouse gas emissions. Additionally, the coconut farming industry encourages monoculture farming, harming biodiversity.
Pea Milk
Pea milk is typically low in calories, high in protein, and has little or unsaturated fat. Like most milk alternatives, companies fortify it with vitamin B12, vitamins, minerals, and other added oils. To minimize consuming large amounts of sugar, consumers should try to drink unsweetened pea milk (that goes for all milk alternatives too!)
Producing pea milk uses far less water and lower greenhouse gas emissions. Like cashews, peas are nitrogen-fixing plants and do not require much fertilizer.
Conclusion
Plant-based milks have both drawbacks and benefits from cow milk. Each milk’s nutritional value and sustainability goals will vary depending on the company and manufacturer. Overall, all plant-based milk will almost always be a better alternative for the environment than cow milk. However, more research is necessary to have a more comprehensive outlook on the sustainability of milk alternatives. Choosing which milk alternative to buy will solely depend on your nutritional needs and environmental goals.
