Humans are the only creatures that drink other animals' milk but increasingly, there's a call for plant-based milk replacements. These alternatives often have a lower carbon footprint, are more humane than milk, and don't trigger any lactose intolerance. But how are they health-wise?
Previous studies have looked at the macronutrients of plant-based milk replacements, noting that plant-based milk typically has fewer calories than cow’s milk and soy is typically the most nutritious of the bunch. But what about micronutrients?
Micronutrients, commonly referred to as vitamins and minerals, are often ignored in the grand scheme of our nutritional planning, often even by those who try to pay attention to what they eat. But micronutrients are essential to the proper functioning of our body, and they absolutely warrant our attention.
"Plant-based milk alternative products have been increasing in popularity, so it is important for consumers to understand how consumption of these products can affect their overall intake of essential mineral micronutrients," explained Dr. Benjamin Redan, Research Chemist at the FDA, to ZME Science. "The minerals we measured in these products are known to play a role in many functions in the body, including normal immune system function, proper regulation of blood pressure/glucose, and bone health."
The researchers explain that despite the growing popularity of such milk replacements, they were unable to find sufficient publicly available data on the micronutrient content across various types of plant-based milk in the US market.
The nutritional content of such products may differ between different brands and whether the product has been fortified in some micronutrients. In fact, when researchers looked at a total of 85 samples from almond, cashew, coconut, hemp, oat, pea, rice or soy milk, they didn't only found significant differences between different product types, but also within brands of the same type of product.
Researchers looked at the content of magnesium, phosphorous, zinc, and selenium -- micronutrients that are not produced by the human body and that are not required on the Nutrition Facts label in the US. Dairy milk is usually rich in these micronutrients, so researchers wanted to see how alternatives compare between themselves and with cow milk.
The team found that pea-based drinks have, on average, the highest content of phosphorus, zinc, and selenium, while soy had the highest amount of magnesium. However, both pea and soy milk had higher levels than cow’s milk.
"Pea-based milk alternative products contained, on average, higher amounts of a majority of the measured mineral micronutrients versus soy-based milk alternatives. Either soy- or pea-based milk alternatives contained higher amounts of the target mineral micronutrients in comparison to the other six types of plant-based milk alternatives we assessed (almond, cashew, coconut, hemp, oat, and rice-based beverages)," Redan added.
"These results indicate that certain plant-based milk alternatives can be a source of mineral micronutrients, but differences across product types should be taken into account when considering their nutritional value."
Researchers also concede a potential limitation of their study, noting that they only assessed the mineral micronutrients, but didn't consider how certain components present in these products may improve or reduce the body's ability to absorb such nutrients (also known as their bioavailability).
However, the team hopes that studies such as this one can help consumers make better informed decisions. Oftentimes, when we want to make an informed decision about purchasing a product, we look at the macronutrients like fats or sugars, but it's also important to keep an eye on the micronutrients
The results have not yet been published in a peer-reviewed journal. The researchers presented their results today at the fall meeting of the American Chemical Society (ACS).