Plant-based milk less nutritious than cow’s milk, finds research

The plant-based milk alternatives category has boomed over the past decade, with market value expected to reach $69bn (€62.45) by 2030, according to Fortune Business Insights.

The primary reason consumers make the switch from conventional milk to its plant-based alternative (most commonly made from oats, soy, or almonds) is linked to health. According to a 2023 survey conducted by Euromonitor International, more than 30% of respondents said they drink plant-based milk ‘to feel healthier’.

The main reason is that shoppers perceive plant-based milk alternatives to be healthy​, Maria Mascaraque, food and nutrition global expert at Euromonitor International recently told FoodNavigator.

But fresh research suggests such perceptions may be unfounded. A study comparing plant-based milk alternative products (PBMAs) with conventional cow’s milk found that the vast majority of PBMAs fall short.

Lower levels of calcium, vitamin D, and protein in plant-based milk​

To assess how the nutritional content of PBMAs compare to that of cow’s milk, researchers examined 223 PBMAs being sold in the US this year from 23 different manufacturers.

For each product, the researchers applied a nutrient calculation programme to estimate full nutrient information. The nutritional content of different products within a category – for example almond milk, oat milk, and soy milk – was compared to both each other and to cow’s milk.

Almost two-third of the products included in the study were made from almond, oats, or soy. Other PBMAs were made from cashew, coconut, flax, hazelnut, hemp, pistachio, rice, walnut, and plant blends.

Findings revealed that compared to cow’s milk, just 12% of the PBMAs contained comparable or greater amounts of all three nutrients studied: calcium, vitamin D, and protein.

Only 16% of the milk alternatives studied had a protein level greater than or equivalent to the 8g per 240ml found in cow’s milk. Soy- and pea-based milk alternatives were more likely to contain higher protein levels.

“Our results provide evidence that many plant-based milk alternatives are not nutritionally equivalent to cow’s milk,” ​commented Abigail Johnson, assistant professor and associate director of the University of Minnesota School of Public Health Nutrition Coordinating Center, who presented the findings at NUTRITION 2023 in Boston this week.

The role of fortification in plant-based milk alternatives ​

The study, which was supported by the Nutrition Coordinating Center at the University of Minnesota, also took notice of fortification in PBMAs.

The researchers found that of the 223 products examined, 170 were fortified with both calcium and vitamin D and that the level of fortification tended to be similar to cow’s milk. A total of 76% of oat milk, 69% of soy milk, and 66% of almond milk alternatives were fortified with both calcium and vitamin D.

“Based on these findings, consumers should look for plant-based milk alternative products that list calcium and vitamin D as ingredients. They may also want to consider adding other sources of calcium and vitamin D to their diets,” ​noted the associate professor.

Johnson believes the findings point to a need to ensure that consumers are aware that many PBMAs in the marketplace are not nutritionally equivalent to cow’s milk. “Product labelling requirements and dietary guidance to the public are among the approaches that may be helpful in alerting and educating consumers.”​

It may be that PBMAs offer other nutritional benefits, however, and that needs to be studied further. Many contain fibre, for example, that may help to meet nutritional needs that cow’s milk doesn’t.

Other benefits associated with dairy consumption?​

The study follows recent research​ suggesting other benefits may be associated with the consumption of conventional dairy.

Earlier this year, researchers from Iran’s Shiraz University of Medical Sciences and Ahvaz Jundishapur University of Medical Sciences examined body mass index (BMI) and dietary intake data from a national cross-sectional study on more than 30,000 Iranians to investigate how consuming fruit, vegetables and dairy may be linked to obesity risk.

Findings suggested that participants who consumed one serving of dairy per day had a 32% lower chance of developing obesity and a 21% lower chance of becoming overweight, compared to those who consumed less dairy. Even when the portions of dairy food were more than two a day, this was associated with 17% lower odds of obesity.

Becoming overweight was found to also be less likely for those who consumed two or more than two servings of dairy per day, compared to those who ate less than a single serving.

But it’s not all good news. Last year, a major research study​ investigating dairy consumption and cancer risk suggested a greater intake of dairy is associated with higher risks of liver cancer and breast cancer in Chinese consumers.

The study, conducted by researchers from Oxford Population Health, Peking University, and the Chinese Academy of Medical Sciences, Beijing, found that for each 50g of dairy consumed by consumers per day, the risk of liver cancer increased by 12% and the risk of breast cancer by 17%.

Senior co-author Associate Professor Huaidong Du, senior research fellow at Oxford Population Health, stressed however that these results should not influence consumers to reduce their dairy intake.

“Whilst our results suggest there may be a direct link between regular dairy consumption and certain cancers, it is important to be aware that dairy products are a source of protein, vitamins, and minerals.​

“It would not be prudent to reduce dairy consumption based solely on the results from the current study or without ensuring adequate intake or protein, vitamins, and minerals from other sources.”​

Sources: Frontier Nutrition
‘The relationship between intake of fruits, vegetables and dairy products with overweight and obesity in a large sample in Iran: Findings of STEPS 2016’
Published online 17 January 2023
DOI: doi.org/10.3389/fnut.2022.1082976
Authors: Mehran Nouri, Zaineb Shateri, and Shiva Faghih

BMC Medicine
‘Dairy consumption and risks of total and site-specific cancers in Chinese adults: an 11-year prospective study of 0.5 million people’
Published 6 May 2022
DOI: https://doi.org/10.1186/s12916-022-02330-3
Authors: Maria G. Kakkoura, Huadong Du, Yu Guo, Zhengming Chen et al.