To sum up the first two parts in this series:
- Talking about sustainability is COMPLICATED.
- There are a lot of different definitions of what is included in sustainability.
- Sustainability measurements often use just one parameter (say, land use or greenhouse gases).
- By most metrics, plant-based foods will be seen as ‘more’ sustainable than animal-based foods.
Though it’s surely not possible, or practical, for me to attempt to combine all the elements of sustainability (as I define it), into one perfect metric whereby I can rank the most and least sustainable foods, that doesn’t mean we should give up hope.
If the question wasn’t complicated, it would likely have already been answered and it is complexity that makes questions worth researching.
As the UN Environmental Protection Agency has explained, a more ‘holistic‘ approach to sustainability is necessary that moves beyond just singular measures of environmental destruction. A more complete model of sustainability understands a sustainable future as reliant upon improvements in environmental degradation and greenhouse gas emissions, in addition to human health, global inequalities and animal welfare.
When these areas are each seen as separate goals, policies can promote one area while hurting another. The classic example is how agricultural policies tend to (supposedly) promote ‘whatever people want’ while health policies tend to (supposedly) promote ‘a healthy diet’. I don’t know about you, but what I want isn’t always going to be the healthiest thing I could order.
The global food system is like a kid who has been given £5 and told to get as much food to feed as many of her friends dinner as possible. She’s not likely to buy a salad or a sandwich; she is probably going to buy the cheapest bulk foods she can — things like crisps, sweets and biscuits. She will succeed in her mission: feeding lots of her friends, but few would say that she gave them an adequate ‘meal’.
In other words: there is a difference between giving people ENOUGH food and giving people ENOUGH HEALTHY food. The current food system supports unhealthy eating because it focuses on calories instead of where the calories come from.
Jennie Macdiarmid, a prominent researcher in sustainable diets, asks the question: Is a healthy diet an environmentally sustainable diet?, the implication being that the two areas are separate and, like one of those Venn diagrams you may have drawn back in primary school, she’s wondering how big the overlap is between the health and environmental circles.
The question shouldn’t be about the overlap, but about the circles themselves. An unhealthy diet is not a sustainable diet. Potatoes are certainly a low-impact food, but if you live your life eating only potatoes, you’re not going to feel so great.
So, in this journey into what makes a sustainable diet we have spent more time understanding what sustainability even is than answering the question. But, don’t worry, the finish line is fast approaching and (hopefully) we can leave with some answers (though probably more questions). Just remember: our understanding of the question is as important as the question itself and depending on how inclusive our notion of sustainability is, we can get a very different answer.
Come back tomorrow for Part 4!