Nutrition vs Sustainability: Can we achieve both?
Nutrition vs Sustainability: Can we achieve both?
Once upon a time if we wanted to eat better, all we had to do was consider the nutrition of a particular food and how we put those foods together to create an affordable and tasty menu. Now we have an additional spanner in the works. Not only must we think about eating for our own health, we must also consider the impact our food choices have on the health of our planet. The worlds of nutrition and sustainability have collided, and our challenge is to understand how we can tick the box for both, crucially important aspects.
To date that has not been easy, primarily because we haven’t had the right information or tools to guide us. We have been fobbed off with overly simplistic messaging such as ‘eat more plants and fewer animal foods’ without much, if any, consideration of the impact such dietary changes may have. Even more so when it comes to individual food swaps such as choosing a plant-based food over an animal food. The questions are: is such a choice always more sustainable? And is it healthier and more nutritious, as is often claimed or assumed?
Fortunately, science is coming up with the goods, with research accelerating in this area to give a much clearer big picture of what needs to be done to create sustainable food systems that also deliver the nutrition we need for best health. And here in Australia, a new food index has been developed to help guide our choices that takes nutrition, environmental impact and affordability into account.  
What is unique about this tool is that it not only considers the nutrient density of a food, but weights the nutrients based on whether they are over or under consumed by Australians. So, for example since almost two-thirds of Australians fail to get enough calcium, foods rich in calcium score more highly.
An environmental impact score is also calculated, so that the two scores can then be compared to take both nutrition and sustainability into account. And finally, each can then also be compared on price to give an understanding about the affordability of our choices.
What’s key to understand is that sometimes we trade nutrition for sustainability.  In other words, we make a food or drink swap with environmental considerations in mind, but by doing so get a far less nutritious food. And often the choice costs more at the same time. Now that might not matter if we get those nutrients elsewhere. Unfortunately, research highlights that this doesn’t tend to happen.
Milk is a perfect example of these various considerations. Is choosing oat beverage instead of dairy milk a better choice?
All varieties of milk, including flavoured milk, scored better nutritionally on the new food index than fortified and unfortified plant-based beverages. Furthermore, the research found that milk, including regular and reduced fat, offered the greatest nutritional value per dollar spent when compared to soy, rice, and both fortified and unfortified oat drinks – making it the most affordable way to address nutrient gaps amongst Australian adults, compared to plant-based choices.
Unfortified oat beverage scored substantially lower on the nutritional index, however if oat milk has added calcium, this score rose – however still only to a fraction of the nutrition found in milk. When looking at the environment related score, this is where the oat beverage ranks higher.
When the nutrient and environment scores are combined the calcium-fortified oat beverage scores highly again, followed by reduced fat milk. Unfortified oat beverage trails far behind, due to its very low nutrient score. In other words, oat beverage is indeed a good choice from an environmental perspective, but it is really the added calcium alone that boosts its combined score.
The picture then changes again when affordability is added to the mix. Oat beverage, whether fortified or not, is double the price or more of milk, but by contrast, milk gives the most nutritional bang for buck.
So, what does all this mean? Let me leave you with two key take-home messages.
1.     Milk is the most affordable and nutritious drink choice. It can be part of a sustainable diet by focusing on the big picture of your overall diet. You can make a far bigger impact to your food-related environmental footprint by eating fewer highly processed junk foods and drinks, and minimising food waste.
2.     If for whatever reason you can’t or don’t want to consume milk, you need to make sure you are getting the key nutrients found in milk elsewhere. Opting for a calcium fortified plant-based beverage such as oat (or soy) is a good sustainable option but do recognise that calcium is not the only nutrient found in milk. You will need to include a variety of other nutrient-rich foods to bridge the gap.
Although the science can get complex, there is much we can do to achieve the goal of a nutritious, affordable and sustainable diet. Keep your focus on the big picture, rather than individual food swaps that often have unintended consequences to your nutrition or your wallet. By eating more nutrient-rich whole foods in the amounts we need (so we don’t overconsume or waste food) and eat fewer highly processed nutrient-poor foods that have big environmental footprints, we get healthier along with our planet.