Plant-Based Milk Lacks Key Nutrients Found in Cow's Milk

Preliminary research suggests that people who consume plant-based alternatives like almond, oat, and soy-based milk may want to keep in mind that many of these products are not nutritionally equivalent to dairy milk.

As more consumers in the United States choose to avoid dairy, many are turning to milk alternatives such as oat, almond, and even potato milk.

However, despite their growing popularity, there has been limited research looking at the nutritional content of these alternatives, leaving many people wondering if plant-based milk products meet essential nutrient requirements.

In a study presented on July 24 at NUTRITION 2023 — the annual meeting of the American Society for Nutrition — University of Minnesota Nutrition Coordinating Center (NCC) researchers revealed more details on how the nutrition of alternative milk stacks up against cow's milk.

To conduct the study, the research team examined the ingredient information of 237 plant-based milk alternatives from 23 manufacturers. They compared the nutritional stats on the product labels to cow's milk and alternative milk in different categories. The team also added each product to the NCC's database, which already contains dietary information for about 19,000 foods.

After analyzing the data, the researchers discovered that about two-thirds of the 237 products were almond, oat, or soy-based. Moreover, around 69% of the alternative milk drinks were fortified with calcium and vitamin D at a level equivalent to cow's milk.

However, the scientists found variations in fortification levels across different alternative milk categories. For example, 76% of oat-based, 69% of soy-based, and 66% of almond-based milk alternatives were fortified with both vitamin D and calcium.

In addition, protein levels in the dairy milk alternatives ranged from zero to 12 grams (g) per 240 milliliters (mL). But only 16% of these products contained protein at levels equal to or greater than cow's milk. Moreover, the researchers discovered that soy and pea-based milk drinks were more likely to have higher protein levels.

Overall, the scientists say that fortified milk alternatives can contain enough calcium and vitamin D, but few of these products have the same protein levels as dairy milk.

While the study results are preliminary and have not yet been peer-reviewed, in a news release, Abigail Johnson, assistant professor and associate director of the University of Minnesota NCC, says, "Our findings point to a need to ensure that consumers are aware that many plant-based milk alternative products in the marketplace today are not nutritionally equivalent to cow's milk."

"Product labeling requirements and dietary guidance to the public are among the approaches that may be helpful in alerting and educating consumers," Johnson adds.

The FDA recently touched on labeling requirements of alternatives in a draft guidance released earlier this year, suggesting these products should clearly state how they differ nutritionally from cow's milk.

Nonetheless, Johnson says that consumers should read labels to ensure they choose a fortified product. In addition, people consuming alternative options may want to consider supplementing with calcium and vitamin D.

In future studies, the team plans to investigate other nutrients found in many milk alternatives, such as fiber, which may exist in these products at higher levels than cow's milk.