What are the benefits and challenges with a plant based diet?
Updated: Apr 27
The global food system, and particularly agriculture, is one of the largest contributors to climate and environmental change. A plant based diet is often put forward as a solution to some of the issues with our system. Could a plant based diet really be the future of food?
Today’s food supply chain produces approximately 26% of anthropogenic GHG emissions. Agricultural production produce the majority of these emissions (61%, and 81% if deforestation is included), 95% of eutrophication, and 79% of acidification.
It's not great to say the least.
Your diet can, therefore, have a huge affect on the planet and it has become clear that changes must be made to what we eat and where we source it from!
Although the percentages of PBDs are still low compared to omnivores (both plant and meat eaters), their numbers have increased recently.
It is estimated that omnivorous diets currently account for roughly 73%, flexitarian (14%), vegetarianism (5%), veganism (3%), and pescatarian diets (3%).
It's important to remember that data on this topic is limited, and further research is needed to get more accurate numbers, but it shows that there is interest in a move to more PBDs.
Here at Floop, we are firm believers that a veggie, seasonal and local based diet is one of the best ways to reduce your impact on the climate.
And, as we are driven by science, and value applying a critical eye to all scientific research we wanted to share an overview of the benefits and challenges currently associated with PBDs.
It is important to remember that this list is not exhaustive and the science is always being updated.
From our research, there are many clear climatic and environmental benefits of a plant-based diet. These include:
Lower GHG emissions. Several studies have examined the diet–climate relationship for PBDs, and there is a general agreement that they result in reductions in GHG emissions per capita.
Less water usage. Many studies have also shown that shifts towards more PBDs, could reduce the need for animal water consumption by 14.4% for blue water, and 20.8% for green water.
Reduced Land pollution, deforestation and soil degradation. For example, the land needed to raise the feed to produce animal protein is 6–17 times greater than for soy protein.
Animal welfare. If we eat more plants, there is less need to kill animals for food.
Of course, concerns have also been raised with the rise of PBDs...
Life cycle assessments (LCAs). Many studies have pointed out how different stages in the food’s life cycle: production, processing, transportation, storage, retail, and disposal can cause variance in the level of impact.
For example: in a study conducted on Swedish tomatoes, it was found that the CO2e per kg of domestically produced tomatoes was approximately 4 times higher than the carrots, due to being grown in greenhouses.
This is an interesting point because it demonstrates how 'local' might not always be as good as we think it is...
Demand for vegetable/fruit products from abroad. The adoption of PBDs has resulted in the demand for more ‘exotic’ products.
Within Europe, avocado consumption, for example, has increased on average by 179% between 2012/13 and 2017/18. Normally produced in tropical climates, where the need for supplementary irrigation is high, the increasing demand places further pressure on the limited water and land resources, often located in developing, low-income countries.
Broadening your diet is great, but it can come at a cost...
Nutritional adequacy. The food industry has adapted to the new trend in PBDs by developing new products that are often aimed to mimicking the qualities of animal-source foods (ASF).
Companies such as Beyond Burger, Quorn, Oatly, and Frankful are a few of the big industry names. Although these new products may be better for the climate and environment, there are limited studies on the health effects of including these products in a PBD.
We all include Ultra-processed foods (UPFs) at some point in our diets, but it's important to remember that just because a product is plant-based it does not necessarily mean it is healthy.
Social Norms. Food choices are a combination of: habit, motivation, attitudes, social norms, self-efficacy, and intention.
Young consumers, predominately in developed countries, are leading in the market demand for more plant-based foods. However, meat consumption is ingrained in many modern-day diets, and it is a difficult task to convince certain population groups to change.
We must be understanding of others and their motivations, and be willing to engage in meaningful discussions.
Economic accessibility. Accessibility of PBDs also needs to be considered as socio-economic barriers can provide huge challenges to the uptake of sustainable PBDs.
Many high-quality plant-based products, both raw and UPFs, are expensive. Certain communities may also face challenges in obtaining the products, due to them not being available in local stores, even if there is willingness to buy them.
This issue needs to be addressed if we are going to achieve our aim for a more sustainable planet!
We hope that this post hasn't confused you too much! Our aim is to show that there is often a lot more to a subject than first meets the eye, and it is important be open to new research and findings.
If you have any thoughts or questions, let us know in comments below.
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