The milk aisle can be an overwhelming place nowadays. With demand for dairy alternatives on the rise due to dietary concerns like lactose intolerance, plant-based diets and allergies, there’s a growing supply of plant-based milks to choose from. Between oat, almond, soy, coconut, rice, flax and hemp milk, choosing the right milk can be confusing. Below we weigh the benefits and drawbacks of the three most popular plant-based milks from both a nutrition and environmental perspective.
The Nutrition Perspective
When comparing milk alternatives, look at both the macronutrients (carbs, fat and protein) and micronutrients (vitamins and minerals). Cow’s milk is considered nutritionally “complete” because it boasts well-balanced macros and is a good source of micros like calcium and vitamin B12. An eight-ounce glass of two percent milk has 122 calories, eight grams of protein, 12 grams of carbohydrates and five grams of fat. The best plant-based alternatives will have a similar nutritional profile.
Generally, dairy milk has more protein than plant milk. And that protein is considered more complete than plant sources because it contains the full array of essential amino acids we need from our diet. On the other hand, many plant milk products are lower in calories, contain less sugar (in unsweetened varieties) and are easier to digest than cow’s milk. These substitutes are also fortified with calcium, vitamin D and vitamin B12 to mimic the micronutrient profile of dairy.
Cow’s milk has been an essential part of human nutrition for thousands of years, but has recently come under scrutiny for its environmental impact. The production, processing and transport of cow’s milk causes three times more greenhouse gas emissions, uses ten times more land and up to twenty times more water than its plant-based counterparts.
Generally, plant milks have a lower environmental impact than dairy across all metrics, but aren’t without their drawbacks. Choosing the “best” alternative depends on which impact – water, greenhouse gas or land use – you care about most. Almond milk, for example, produces fewer greenhouse gas emissions and uses less land than soy milk, but requires much more water.
Of the plant-based milks, soy milk is the most nutritionally similar to dairy. It boasts the highest protein content of the popular plant milks and has the added benefit of being high in fiber and omega-3. It’s also a good source of micronutrients like manganese and magnesium, and is often fortified with essential vitamins and minerals such as vitamins A, D, B12 and calcium.
There are environmental concerns surrounding soy production, as demand for soy contributes to deforestation in the Amazon. However, the largest driver of deforestation is beef production, and about 77 percent of soy is used for animal feed, not direct human consumption.
Almond milk is the most popular non-dairy milk in the U.S., occupying about two thirds of the market. It is a low-calorie option that offers healthy unsaturated fats and vitamin E. When fortified, it also offers calcium, vitamin D and magnesium in amounts comparable to cow’s milk.
However, almond milk does take its toll on the environment. Growing almonds is highly water intensive, requiring about 15 gallons of water to produce just 16 almonds. Considering 80 percent of the world’s almonds are grown in drought-stricken California, the rising demand for almond milk requires farmers to divert ground and surface water from California’s aqueduct system to irrigate crops, which can deplete residential drinking water supplies. Despite this, producing almond milk still takes less water than cow’s milk. Almond milk lovers are encouraged to alternate between plant milks or try making their own almond milk.
Oat milk is now the country’s second most popular plant milk after growing by 182 percent from 2020 to 2021. It offers fiber, iron and folic acid, and like other fortified plant milks, has substantial amounts of vitamin A, vitamin D and calcium. This substitute is also naturally sweet, as processing the oats breaks the starches down into a natural sugar called maltose.
In terms of environmental impact, oat milk performs well on all metrics: it is water efficient, requires little land-use change and produces few greenhouse gas emissions. However, some oat crops are sprayed with glyphosate, an herbicide that may be linked to cancer. The Environmental Protection Agency has stated glyphosate poses little risk to humans as long as it is used properly. To be safe, it’s best to opt for organic oats and oat milk when possible.
While plant milks are never a direct substitute for the real thing, they can be part of a balanced diet. It is up to you to decide which milk best suits your nutritional needs, taste preferences and environmental goals. Overall, try to opt for organic, unsweetened and unflavored varieties to avoid too much sugar and other unwanted additives.