THE OPTIMAL DIET FOR ALL LIFE ON PLANET
A PLANT-BASED DIET HAS THE LOWEST ENVIRONMENTAL FOOTPRINT AS IT LOWERS
GREENHOUSE GASES EMISSIONS AND RESTORES THE SOIL
INTRODUCTION TO ACADEMIC SKILLS
CASTELLI EMMA, i6289079
October 14, 2021
Introduction
“Food systems have the potential to nurture human health and support environmental
sustainability; however, they are currently threatening both” (Willet et Al., 2019).
Providing the growing global population with healthy diets from sustainable food systems is an
immediate challenge. Until now, the current food system has managed to keep global calorie production
at pace with population growth; however, this is becoming a relevant problem as 820 million people still
have insufficient food to meet their daily needs. Furthermore, the global population is finding itself with
hurtful projections of healthy years in their life span -that are, overall, becoming less as time proceeds
(Willet, 2019). When it comes to climate change and environmental pollution, usually the use of oil, gas
and petrol is the first topic to be tackled; despite this, the role that human food consumption and diet
have concerning climate change has been vastly underestimated and neglected (Rosbotan, 2009). This
paper will conduct a critical evaluation of how the current food system is environmentally unsustainable
and is contributing in polluting the planet and why a plant-based diet (i.e., diets that are focused on the
consumption of plants or plant-based alternatives) is the possible most sustainable form of eating; in the
following paragraphs an option will be discussed that can be taken into account to create a more
efficient food production and consumption system, one that can fulfill the growing demand- while at the
same time nurturing the planet with soil restoration, the so-called “Regenerative agriculture”. The final
aim is to help spreading awareness on the overall benefits that can derive from introducing more plantbased foods in our daily lives, nurturing not only human’s health, but also the one of the planet.
Sustainability of plant-based diets
The importance of a plant-based diet for planetary health was widely summarized by the EAT - Lancet
Commission in 2019 -a commission of world leading doctors, scientists and food system experts that
collaborated with academic journal “The Lancet”. This commission aimed to tackle the shifts that will be
much needed in order to be able to feed an estimated population of ten billion people by 2050, aiming
for a future where the health of the global population -as well as the one of the environment- are not
irreversibly damaged (Willet, 2019). In this report, the commission clearly stated that the only way to
decrease global pollution as the population rises, would be to double consumption of fruits, vegetable,
nuts and legumes, as well as reducing consumption of red meat and sugar by at least 50% (EAT-lancet,
2019). Currently, meat -and especially red meat- consumption is increasing exponentially on a global
scale, as developing countries are assuming a “western”-like dietary pattern, thus not only increasing
their daily meat consumption but also their overall consumption of animal products. Said increase is
becoming problematic especially because meat and all animal-based products -including dairy- have a
very negative environmental footprint, being responsible for the emission of several greenhouse gases
(GHGs) -such as methane, nitrous oxide and carbon dioxide (CO2) (EAT-lancet, 2019). The carbongenerating inputs required by animal farming, the methane produced by these same animals as they
digest their food and the nitrous oxide produced by decomposing manure adds up making the livestock
sector responsible for at least 14.5% of global GHGs each year (FAO, 2021). As opposing to animal and
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livestock agriculture, plant agriculture results in significantly fewer emissions than animals raised for
food -whether it’s dairy or meat (Chai et al.,2019).
In fact, a 2018 study from a group of researchers at Oxford University compiled data on the
environmental impact of different foods, pointing out that producing one hundred grams of protein
from peas is responsible for 113 times less GHG emissions than producing the same amount of protein
from beef (Poore, 2018). These findings are problematic since -as mentioned previously- developing
nations are increasing their meat consumption by the year, thus, increasing the total levels of GHG
emission; if the global population will continue to rise at the current rates, it is projected that by 2050
there will be 10 billion people to feed on this planet (EAT-lancet, 2019).
A 2020 study published in the Journal of Global Environmental Change analyzes the environmental
footprints of different dietary patterns in 140 countries, identifying that a plant-exclusive diet reduced
GHG emissions by 70% compared with the typical omnivorous diet (Kim, 2020). Given the above, it is
becoming necessary to improve the consumption of plants -or plant-based alternatives- in one’s diet,
decreasing animal products production and purchase and thus diminishing the overall environmental
footprint.
Regenerative agriculture
With the global population increasing drastically, the challenge is becoming that to be able to feed more
people than ever before in a way that substantially reduces the emissions generated by global foods
systems. To achieve this, many ideas have been put forward across the world, such as the concept of
regenerative agriculture, a principle of farming that seeks to nurture the ecosystem services and
produce food in a way that is not just sustainable, but regenerative in the sense that it aims to restore
health of dying soils, enhance biodiversity and make crops more resilient to droughts. These principles
explicitly apply to plant agriculture, but also to a relatively new form of pastoralism called “holistic” or
regenerative grazing, a particular method of rotating livestock over pasture that has garnered increasing
international attention with its proponents stating that it should be seen as a key solution to reverse
climate change, and essentially a reason for people to deny the environmental superiority of a plantbased diet and increase their meat consumption (Nordborg, 2016). Although this method of animal
agriculture may seem beneficial -or at least ethically better than intensive grazing methods-, a recent
meta-analysis looking into the effects that grazing has on climate change found that it is still a very much
net CO2 emitting practice: even though specific forms of grazing can help sequestering CO2 from the soil,
the practice as a whole produces significantly more GHGs -particularly methane- than it is able to
sequester from the atmosphere (Garnett, 2017); moreover, regenerative “holistic” grazing uses far more
land space as opposed to its more-efficient but less-ethical “twin” (i.e., intensive animal agriculture).
For this reason, better grazing-induced removals of CO2 from the atmosphere via soil carbon
sequestration do not offer a substantial mitigation opportunity for what concerns climate change.
Furthermore, any shift towards holistic grazing would mean a dramatic reduction in overall meat supply
of around 75% - a problematic aspect since global demand is increasing. Conclusively, advocating for
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holistic grazing would mean advocating for greater shift to plant consumption as well (Hayek et al.,
2018; Hill, 2021).
As for regenerative plant agriculture, carbon sequestration occurs primarily by means of photosynthesis;
thus, through plant cells’ respiration (National Geographic Society, 2019). Grasslands and forests are
hence the major carbon-sequestering ecosystems known, and animal agriculture has been proved to be
the driving cause of deforestation worldwide, especially in the tropics, where -being the “green lungs” of
our planet- the tropical forests sequester more than ten million metric tonnes of CO2 per year (Du et al.,
2018; Mitchardet, 2018; Bennet, 2017). This preoccupying deforestation phenomenon is likely to keep
rising in the future if more land will be needed to raise cattle -as Hayek et Al. found that global meat
demand is increasing. As follows, a vicious cycle of emissions and deprivation of possible sequestration
methods (i.e., forests and plant crops) will be created, resulting in much greater environmental damage
caused merely by unsustainable meat-focused eating practices. It is clear that as global population
increases, land use must become a concern; wherefore, regenerative plant agriculture may be the
perfect solution not only for what concerns CO2 sequestration, but also -and most importantly- to
replenish soil’s minerals and prevent desertification (Rhodes et al., 2012). Nevertheless, regenerative
plants agriculture could also seriously improve global food supply, as the majority of plant crops are
nowadays fed to farmed animals, leaving 820 million people unable to meet their daily food
requirements. A restoration of the soil could hence help switching globally from soy crops -75% of which
is fed to farmed cattle and poultry- to a variety of other plant crops, providing a generally large and
varied food supply that can be distributed widely while sequestering CO2 from the atmosphere and
regenerating the soil underneath (Willet et al., 2019, Hill, 2021).
Conclusion
As the global population is rising, finding a sustainable food supply method is becoming a problem: meat
and other animal-based products’ demand is rising, and it is becoming unsustainable for the meat and
dairy industry to meet this demand unless more land is sequestered and dedicated to cattle farming.
This problem is what makes the animal industry the greater cause of global deforestation and
desertification of lands; said industry is also one of the greater emitters of GHGs, which are a major
threat to climate change, as they enhance global warming. The factors discussed call for a substantial
need to shift one’s dietary choices towards a more plant-based approach, utilizing plant-based
substitutes and alternatives instead of meat and dairy, hence lowering one’s environmental footprint.
The animal agriculture industry proposed a solution that might help sequester from the atmosphere the
emitted CO2 and GHGs (i.e., holistic grazing), but the data amongst the literature prove that this
wouldn’t be an efficient way to do it. The majority of global plant agriculture is dedicated to soy that is
fed to farmed animals; if treated using regenerative practices (i.e., regenerative (plants) agriculture), a
restoration of soy crops used to feed cattle and poultry could offset CO2 emissions as well as regenerate
the soil preventing desertification. Therefore, increasing the consumption of plants in one’s diet could
help drive the demand towards a more environmentally sustainable land use, restoring the soil and
sequestering CO2 from the atmosphere.
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