Holy cow - milk is best!

These are the findings of a new study, published in the Frontiers in Nutrition journal (August 8), which assessed the nutritional profiles of a range of plant-based beverages – such as soy, oat, coconut, almond or rice drinks – and compared them to standard bovine milk.

Researchers collected 103 plant-based products from supermarkets in Palmerston North, New Zealand. These drinks were found to have much lower quantities of the 20 nutrients measured – such as calcium and protein – and were significantly more costly than cow’s milk.

The study was carried out by Riddet Institute scientists, from Massey University, in Palmerston North. The Riddet Institute is a Centre of Research Excellence (CoRE), hosted by Massey University.

Plant-based beverages are often marketed as alternatives to ruminant milks such as cow’s milk, and consumers could easily believe they’re nutritionally interchangeable. However, this research demonstrates they are not the same. In fact, it is “nutritionally risky” for consumers with high nutrient demands like pregnant women and young children to replace cow’s milk with plantbased products.

Milk as a food supplies 49% of the world’s calcium and it’s one of the most important things about milk.

This independent study surveyed the prices and nutrition labels of the products and then nutritional content was analysed in an external accredited laboratory. Selected almond, coconut, oat, rice and soy products were tested for their macronutrient and mineral content.

One of the researchers noticed that in storage you get a really thick layer of semi-solids on the bottom and then a watery layer on the top. He wondered what happened to the distribution of nutrients with sedimentation.

Further tests were done before and it was found that many of the nutrients like protein and calcium remained in the sediment in the plantbased beverages if you did not shake the product before consuming. This was not the case for the cow’s milk.

The protein content of cow’s milk was in the range of 3.3-3.9g per 100g. Only soy drink had a comparable content to cow’s milk, with all other plant-based beverages containing less than 1.1 g protein per 100 ml on average.

Most plant products were ultra-processed and fortified with calcium and minerals with additives like sugar, fats, hydrogenated oils, hydrolysed proteins, flavours or thickeners. Oat and almond beverages contained as little as the equivalent of half a cup of oats or six almonds in 250g of product.

The plant-based beverages were often promoted as having no added sugar, but milk also does not have added sugar. Lactose (in milk) is also poorly converted to glucose in the body, which means milk is quite low in what we commonly call ‘sugar’.

Plant-based beverages have plant equivalents to ‘sugar’ that do convert to glucose in the body. That is why plant-based beverages often have a natural sweetness and don’t need added sugar. But they cannot be considered low in sugar.

Meanwhile, the argument for the alternatives being more environmentally sustainable also did not stack up, when considering how much product would need to be consumed to achieve the same nutritional benefits as conventional milk. With some plant-based beverages you would need to have 18 serves to get the same amount of protein, for example, as a single serve of milk. This comes at a much higher cost to the environment – and the wallet.

It was not all bad for the alternatives, with plant-based beverages supplying some nutrients that milk does not, such as fibre.

The final conclusion is the plant-based beverages and bovine milk are not nutritionally similar in any way. They are completely different foods.

If you want to use alternatives, do so, but do not consume them with the belief that they are nutritionally similar substitutes for cow’s milk.

Warren McNabb was one of the study’s authors and is Professor of Nutritional Sciences at the Riddet Institute.