How Milk Compares to Plant-Based Beverages

Milk is a natural choice

Canadian milk is a naturally nutritious and minimally processed choice. In contrast, plant-based beverages are processed formulated products. They often contain very little plant matter and many other ingredients. For example, a glass of almond beverage typically contains just a few almonds and is mostly water with added salt, flavouring and thickening agents as well as added sugar in the case of sweetened versions.

Protein matters at all ages

Protein plays a fundamental role in building and repairing bones and muscles throughout life. Cow’s milk is an excellent source of complete protein with 9 grams per 250 ml.¹ On the other hand, people often don’t realize that most plant-based beverages (except soy beverages) provide very little and/or incomplete protein.² For example, almond beverages provide only about one gram of protein per 250 ml, and rice and coconut beverages provide even less.¹

Milk helps fill nutrient gaps

Cow’s milk is also a reliable source of many essential nutrients.² In fact, milk products are a key source of 6 of the 8 nutrients that many Canadians don’t get enough of, including calcium, magnesium, potassium, zinc and vitamins A and D.³ Regulations in Canada ensure that cow’s milk is fortified with vitamin D. Vitamin A is also added back to lower fat and skim milk to replace the amount that is removed during the skimming process. While fortified plant-based beverages may have added nutrients, fortification is inconsistent and varies widely by type and brand.²

Cow’s milk is recommended for young children

Milk and dairy foods are especially important for building bone mass in growing children and teens. Canadian public health dietitians have expressed concern about parents feeding their infants and young children plant-based beverages.⁴ A number of infants and young children have become malnourished after they were fed plant-based beverages as their main beverage.⁵

A 2017 joint statement from the Canadian Pediatric Society and Dietitians of Canada advises parents that because most plant-based beverages are very low in protein, fat and calories they may not be able to support good health and optimal growth in children 8 years of age or younger.⁴ Once an infant or toddler is ready to transition from breast milk or formula after nine to 12 months of age, Health Canada also recommends cow’s milk as the main milk.⁶ More specifically, full-fat homogenized (3.25% M.F.) cow’s milk is recommended until the age of two years. Plant-based beverages, even if fortified, are not recommended as a main milk for children younger than two years.

A 2019 report from the American Academy of Pediatrics, the Academy of Nutrition and Dietetics, the American Academy of Pediatric Dentistry and the American Heart Association recommends cow’s milk and water as the preferred main beverages for children two to five years.⁷ This report advises that plant-based beverages are not recommended as the main milk source for early childhood, unless medically indicated or to meet specific dietary preferences. 

Cow’s milk helps meet children’s nutrient needs

A 2017 Canadian research study concludes that children who drink other beverages such as plant-based beverages instead of cow’s milk are shorter than children who drink cow’s milk.⁸ The height difference was 1.5 centimetres for three-year-olds who drank three cups of cow’s milk per day compared to those who drank other beverages such as soy or almond beverages. Children who drink plant-based beverages may consume less protein and fat than those who drink cow’s milk, resulting in reduced growth. The authors note that other studies have found similar increases in height in children who consumed cow’s milk.⁸ Optimal growth is an important indicator of health in young children.

Findings from an earlier 2014 Canadian study indicate that young children may also risk not getting enough vitamin D when plant-based beverages replace cow’s milk.⁹ Children who drank only almond, rice or soy beverages were more than twice as likely to be deficient in vitamin D.

Nutrient bioavailability is key

The bioavailability of nutrients, that is the degree to which the body can absorb nutrients from specific foods, is a key concern. Cow’s milk has a number of advantages compared to plant-based beverages when it comes to the bioavailability of bone-building minerals such as calcium.¹⁰

First of all, some research shows that up to 40% of the calcium added to fortified plant-based beverages tends to settle and stick to the bottom of the container, even after shaking vigorously.¹⁰ From a practical standpoint this means that much of the calcium added to plant-based beverages is unlikely to actually be consumed. Furthermore, some types of calcium that are added to plant-based beverages may be only 75% as well absorbed as the calcium naturally found in milk.¹⁰ Moreover, plant-based beverages may contain plant substances identified as ‘antinutrients’ that can interfere with how well the body absorbs essential minerals such as calcium, magnesium and zinc.¹⁰

Additionally, preliminary data suggests that soy intake (which includes soy beverage) is associated with a reduced endogenous conversion of alpha-linolenic acid into eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), two essential omega-3 fatty acids that have important essential physiological functions in human health.¹¹ In a 2021 Canadian study of 1083 adults, soy intake was associated with a lower desaturase activity, an enzyme involved in the endogenous conversion process. While this study’s findings remain exploratory, the authors note the potential ramifications of their results, as soy-based products have increased in popularity in recent years and omega-3 intake is already insufficient in the general population.

Cow’s milk and oral health

Milk’s protein content and highly bioavailable calcium work together to protect tooth enamel.¹² On the other hand, emerging research suggests that regularly drinking plant-based beverages, especially those with added sugar, may erode tooth enamel and lead to cavities.^10,13

The bottom line

A large body of evidence supports the benefits of drinking cow’s milk as part of a healthy dietary pattern. On the other hand, there’s relatively little research on the health effects of plant-based beverages. As plant-based beverages are growing in number, it’s also important for Canadians to know the nutritional differences between cow’s milk and plant-based beverages.