A recent CBC article reports on a new joint statement from the Dietitians of Canada and the Canadian Paediatric Society that says plant based milks are “inappropriate alternatives to cow milk in the first two years”, citing their lack of protein, lack of fortification (most cow’s milk is fortified with a subset or all of vitamin A, D and C), sugar content and potential to “displace hunger”. So let’s take a look at the nutrition of plant based milks.
You’ve probably heard of soy and almond milk, maybe even rice and coconut milk, but there are actually many more types of plant based milks, each with different flavours, uses and nutrient contents. Soy milk has the most protein of any plant based milk, and was the generally preferred plant milk for a number of reasons, including its mild taste, functionality when cooking, and not least of all, the fact that soy was already being grown around the world, both for culinary uses and livestock feed. In recent years however, almond milk has overtaken soy milk’s spot atop the plant milk popularity podium, and now makes up about 2/3 of the US market. Some other popular plant milks include rice, coconut, hemp, oat, cashew and hazelnut and pea.
There’s a lot of debate to be had for what milk is best for the environment. Raising livestock has a large impact on the environment, due to methane emissions, providing animals with food and water, and the pollution that may result from their waste, but plant based milks may not be the best alternative if saving the trees is your goal. Soy bean cultivation has recently been heavily criticized for causing deforestation, and almonds haven’t faired much better, as a recent statistics say that it can take as much as 4 L of water to grow a single almond.
Before your idea of nature saving plant milks is completely ruined however, it is worth noting that buying organic soy, almond or other milks can have a huge difference in how they’re grown. In Canada, any product affixed with the official “Canada Organic” logo has to be grown according to some rather strict rules that affect everything from manure sources to mandatory nutrient cycling programs, meaning that while still potentially impactful, organic plant milks are probably the best bet for minimizing the environmental impact of your cereal.
Canadian nutritional labels feature a familiar chart that breaks down the amounts of certain macro and micro nutrients in terms of percents of daily amounts needed for the average adult. Finding information on recommended nutrition for a child’s diet proved more challenging. After quite a bit of googling, I eventually found the official Canadian dietary reference intake charts, which covers all ages and molecules.
Canada’s Official Food Guide instructs adults to “have 500 mL (2 cups) of milk every day for adequate vitamin D.” In Canada 2% milk is the most popular, and has between 2.8 micrograms (mcg) (according to this government of Canada document) and 6.75 mcg (according to the nutritional information from Nielson Dairy) of vitamin D per glass, which means that 2 cups has between 5.6 and 13.5 mcg which, depending on the brand of milk you buy, provides between 30 and 90% of the recommended daily vitamin D intake for all ages. The Food Guide does offer an option for those of us who don’t drink cow’s milk, telling us to drink “ fortified soy beverages if you do not drink milk” in several different places.
Now that we have an idea the nutrition that kids and adults need, let’s break down the case against plant milks, and look at the science. First, the Paediatric Society says that “some plant-based beverages are not fortified with any minerals or vitamins” While almond, rice or plant milks other than soy seem to vary on whether they’re fortified or not, when looking at the major brands of soy milk, both sweetened and unsweetened, I couldn’t actually find any that were unfortified. A quick glance at the data (compiled in the chart below) shows that most brands have as much calcium as cow’s milk, and some have more. When it comes to vitamins, it’s not even a contest, the average soy milk serving has at least double the vitamin D content of cow’s milk. So while the recommended 2 cups of cow’s milk may only get a drinker 30% of their daily vitamin D, 2 cups of soy milk will get a drinker 60-90% of their vitamin D. Neither milk offers enough vitamin D on its own, but soy milk is certainly comparable to its cow alternative.
Next up is the claim that plant milks “often contain sugar as the second ingredient after water”. As a list of ingredients is in order of magnitude, having sugar as the 2nd ingredient implies that these milks are full of it. But in truth most plant milks have relatively few ingredients, so being 2nd on the list doesn’t mean much for sugar. It’s must more informative to look at the grams of sugar found in one serving of a milk. Health Canada recommends that sugar intake not exceed 25% of your daily calories, which puts the acceptable amounts around 100g of sugar a day, which 2 cups of any milk is not coming close to, regardless though, less sugar in a diet, especially a children’s diet, is rarely a bad thing. Cow’s milk has 12 - 13g of sugar per cup, whereas original (sweetened) soy milk has around 5-7g per cup. Unsweetened soy milk has even less, at around 2g per cup. It’s easy to see that regardless of ingredient list, soy milk has half the sugar of cow’s milk.
After the sugar argument comes the protein argument, with the article saying that “Kids aged two to eight need 13 to 19 grams of protein per day, which can be met with two cups of cow milk or two cups of fortified soy beverage,” and then in the same breath stating that “plant-based beverages, including soy milk, are "inappropriate alternatives to cow milk in the first two years.” Huh?! Looking at the data it’s pretty clear that soy milk has comparable amounts of protein to cow’s milk, although neither offer enough protein for even a small child in 2 cups alone.
When it comes to the fat content of milks, the CBC article says "We do not want to restrict fat at all for the first couple years of life”. That sentence actually has a couple problems, as for one the WHO recommends exclusive breastfeeding of infants until 6 months at the minimum, and preferably until at least 2 years of age. But if a child is having milk other than breast milk, the data shows again that soy milks contain comparable amounts of fats to cow’s milks, so a switch to soy isn’t going to be restricting a child’s fats much.
Lastly the article states that “drinking too much of the plant-based beverages can displace hunger and cause children to eat less food” which is the claim I find the strangest, since cow’s milks contain more calories and carbohydrates than soy milks, and the 2 contain about the same amounts of fats. Cow’s milk would be much more effective at displacing hunger, particularly when compared to plant milks like almond that have few calories, fats or carbohydrates.
I’m not a dietician, but from examining the data, I’m struggling to see any reason that soy milk could not be safely substituted for cow’s milk in children older than 2. What I do see is a news article that didn’t spend as much time researching plant milks as I did.