It is that time of the year again: Not only are many of us trying to lose weight after the Christmas eating frenzies, Social Media is full of vegan recipes. It is Veganuary, the vegan diet awareness month. The proposed challenge (the most famous example for a January challenge to change behaviour and habits on the long term) is to eat plant-based for all of January. A vegan diet is often claimed to be healthier, but is it better for the environment? Let’s look into it!
The eco-footprint of animal products
The reason why plant-based diets are promoted as being good for the environment lies in the negative effects of the production of animal products on the climate. Especially in terms of Greenhouse Gas emission, the production of animal products is much worse compared to the growth of plants e.g. like wheat:
For the same amount of produced climate gas you can grow 1 kg of beef, 6 kg of pork or 14 kg of poultry – or even 113 kg of wheat [5,6]. Also in terms of water and land use, the production of animal products is much less resource-efficient than that of plants [1,2,3]. For more details, please see my article dedicated to this topic here!
This can be extended to many other vegetables as well. Since we can directly consume calories from vegetables, they are in almost all cases better for the environment than feeding them to animals first; only to then consume products made from these animals.
The efficiency of animal products is just so much lower because their production is much more elaborate. It takes significantly more resources to keep and feed an animal until it can be consumed as meat. Eggs and milk are less pollutant than meat as animals can make them more effectively than they can grow muscle, but still they are no match to their vegan replacement products such as plant-based milk.
This is why eating less meat or switching to a vegan diet completely is being promoted as so good for the environment. And in fact, it is one of the most effective ways to decrease your own personal ecological footprint [4]! But does this mean that a vegan diet is automatically more eco-friendly and sustainable?
Is a vegan diet always more sustainable and eco-friendly?
In general, the answer can definitely be yes, while for special cases it can also be no. Especially when we are looking at the animal product replacements such as plant-based milk or meat replacements, these are surely better for the environment and climate than their animal-based counterparts. But if we have a closer look, there can be certain problems with plant-based diets:
- Transportation can be a big issue, especially for exotic or off-season fruit and veggies. Once these are imported by air from far away places such as South America or Africa, their Greenhouse Gas emission rises significantly. A prominent example for this is asparagus from Peru: It is sold all year long and imported in most cases by air. This consumes 54% of the primary energy demand of asparagus in general during its life cycle, making it the highest energy consuming vegetable compared in a large study in [7]. Big, perishable fruit like melons are similarly problematic, because their transport is especially inefficient due to the size of the fruit.
- Production can also be critical: Depending on the climate conditions, growing certain crops in some areas can cost extended amounts of energy, land or water. Avocados for example are grown in countries where water is scarce already, but their production is highly intensive in terms of water use [8]. Same is valid for nuts such as cashew nuts or almonds [9]. Similarly, production of vegetables in (heated) greenhouses is much more resource-intensive than the production of local produce on farm lands.
- Processing of the vegetables can also have a high impact: Especially for potatoes, which are in many cases processed to chips or crisps, this can account for high energy consumption [7].
Because of these contributions, it is possible to have a higher eco-footprint than the average flexitarian or meat lover even when living on a strictly plant-based diet! It just depends on the composition of the diet eaten. If the vegan diet is focused on imported and resource-intensive produce, this is surely a big problem for the environment!
What is a sustainable, affordable and healthy diet?
To mitigate the effects of transportation and production, eating seasonal and local produce is the easiest and most effective strategy: These fruits and vegetables are the most environmentally-friendly and luckily also fairly cheap! Of course, reducing meat consumption and replacing animal products with plant-based alternatives are also highly effective to reduce the climate impact of one’s diet. In terms of healthiness, it is advisable to eat a balanced diet, which is also advantageous for the environment. As a general and easy rule of thumb, eating according to a vegan meal plan with a low amount of imported produce is the best way to go.
Are you also joining Veganuary or do you have a different New Year’s resolution? Share in the comments!
References:
[1] https://www.boell.de/de/2015/01/08/futtermittel-viel-land-fuer-viel-vieh
[2] https://www.pnas.org/content/pnas/111/33/11996.full.pdf
[3] https://pdfs.semanticscholar.org/b7bd/ac7e17929013b428930f5b1f983cc36f3f84.pdf
[4] https://doi.org/10.1088/1748-9326/aa7541
[5] https://doi.org/10.1016/j.anifeedsci.2011.04.058
[6] https://doi.org/10.1071/CP11191
[7] https://doi.org/10.1016/j.scitotenv.2019.04.424
[8] https://www.sciencedirect.com/science/article/abs/pii/S0959652620349611
[9] https://science.sciencemag.org/content/360/6392/987.long
