Food is an extremely polarizing topic due to its importance in our everyday lives and its massive impacts on the environment. In 2018, food systems released about 16 Gt of CO2e in the atmosphere [160 billion pandas] – equivalent to roughly 33% of our global GHG emissions the same year. Note that many reports have more cautious estimates, like the IPCC’s 21-37% range.

Including the effects of land use conversion like deforestation, the farming stage [i.e. excluding food transport, supply chains, or waste disposal] accounted for 65% of food’s GHG emissions in 2018. Unfortunately, there’s more to it than just GHGs. Our food systems also caused 32% of terrestrial acidification and 78% of eutrophication in 2018, which can destroy both ecosystems and biodiversity.

Many factors can increase a food product’s footprint, such as cooking methods, transportation, and packaging – but it’s clear that the farming stage has the highest impacts of them all. So it’ll be the main focus of this section.

Personal diets aside, it’s important to understand that our food systems are causing environmental crises in some of the most biodiverse parts of the world. Simply put, the current food system needs to become more sustainable. Not only to reduce our present impacts, but also to ensure food security for an increasing and increasingly demanding population.

Land and Population

In 2019, around 51 million km2 of land were used for agriculture [i.e. farmland, which includes pastures for animals and fields for crops]. That represents around 50% of the Earth’s habitable land area. Farmland area will continue to grow if we don’t change our food systems, since we’ll soon need more food for a growing population. In fact, worldwide food production is expected to grow by roughly 48% from 2013-2050.

On top of population growth, many densely populated countries are still developing, and their populations are getting richer. Many who were constrained to eat smaller rations of local products can now eat larger meals like developed countries – with ingredients imported from all over the world. For example, China’s middle class – which has grown from roughly 80 million in 2002 to 700 million in 2020 – has increased the country’s average meat intake significantly in the past 60 years.

Meat consumption by selected country 
Average annual consumption per person 
Source: UN Food and Agriculture Organization / Our World in Data 

The ever-increasing demand for arable land is a big problem since land area is finite. The current solution seems to be burning/cutting down forests and other green ecosystems to allow crops to grow instead, but this is proving costly for the environment. Land use conversion [e.g. deforestation] leads to emissions, biodiversity loss, and lower carbon capture rates– as vegetation currently absorbs around a quarter of annual CO2 emissions.

It’s not all about land either. Aquatic ecosystems are being severely polluted because of our unsustainable food practices [e.g. chemical runoff causing eutrophication]. Fishing and aquaculture farms are threatening many marine ecosystems as well, mainly through careless fishing techniques and over-fishing.

Instead of resorting to land use conversion, pesticides, herbicides, or genetically modifying crops to increase food production temporarily, let’s see how easy it is to improve our food systems from the consumer side of things.

Food Emissions and Land Use

No matter our diet, it’s important to understand how much our food pollutes before we eat it. The following graph shows the extent to which different products release GHG emissions during their life-cycle. Quickly zooming in on the next graph and finding the ingredients we eat the most can help us acknowledge how our everyday meals impact the environment.

Clearly, animal products are the highest-impact foods. However, there are a few other products that emit loads of emissions as well – like coffee, chocolate, and oils.

Whether we eat meat or not, we all consume some of the foods shown in the graph. And we’re not the only ones. Cattle [i.e. cows and bulls] don’t only eat grass like they do in cartoons, just like pigs don’t eat mud.

The Food’s Food

While ruminants [e.g. cattle, sheep, goats, etc…] do consume roughly 2.7 billion tonnes of grass per year and 65% of this grass grows on unfarmable lands – that still leaves 35% of grazed land where lower impact foods could be grown instead. Now, this alone doesn’t mean anything – pastures are wonderful ecosystems that naturally require grazing to remain unchanged. No one should suggest that all pastures be turned into forests.

However, to satisfy the demand for ruminant meat, milk, or skin, the current food system is relying on agricultural expansion and intensive pasturing techniques.

It’s also important to note that a massive proportion of crops end up as feed. It’s estimated that around a third of all crops are grown to produce livestock [i.e. all farmed animals] feed, using 38% of our arable and permanent croplands worldwide.

Regardless of whether livestock eat grass, feed, or even food by-products we can’t eat – it’s simply undeniable that they take up a lot of room. And with the significant increase in animal product consumption in recent decades, that has led to unsustainable agricultural expansion.

Agricultural Expansion

Farmlands cover around 50% of the Earth’s habitable surface. Since the Earth is fully booked, increasing that percentage ever so slightly has usually led to deforestation and land use conversion of other green ecosystems. In fact, it’s estimated that agriculture was responsible for around 73% of tropical deforestation worldwide from 2000-2010 [with tropical deforestation accounting for roughly 95% of total deforestation]. That’s a pretty big problem considering vegetation sequestrates loads of carbon in biomass and soils – while land use conversion releases that carbon back into the atmosphere. This explains why land use conversion is one of agriculture’s highest GHG-emitting activities.

On the surface, it might seem like croplands are responsible for most of the deforestation occurring within the food industry, instead of livestock. Digging deeper though, it’s clear that animal products have the largest impacts, as roughly 67% of deforestation for agriculture [i.e. conversion of forests into farmland] aims to grow livestock feed.

The food industry is well aware of the lack of space. We simply don’t have room to grow food for so many animals.

Aside from land use conversion, the industry’s current solution seems to be reducing each animal’s living space so that they’re only able to move a few inches in a certain direction. Not only is this an inhumane solution, it’s also unsustainable. Instead of dealing with the consequences of the problem, we should try and modify the root cause. Only then can we develop food systems that can be sustained for the foreseeable future.

Food’s Inefficiencies and the Food Chain

From a purely nutritional perspective, eating meat can be considered inefficient. Per unit weight or protein content, livestock consume more food than they give back. While that would be acceptable if they were only eating inedible food scraps [i.e. feed requires no additional land or resources], that’s not the case.

Protein efficiency of meat and dairy production 
The protein efficiency of meat and dairy production is defined as the percentage of protein inputs as feed effectively 
converted to animal product. An efficiency of 25% wou Id mean 25% of protein in animal feed inputs were effectively 
converted to animal product; the remaining 75% would be lost during conversion. 
Whole Milk 
Source: Alexander et al. (2016). Human aoorooriation of land for food: the role of diet. Global Environmental Change. 
Our World 
in Data 
Source: Our World in Data (2019) Meat and Dairy Production. Licensed under CC-BY.

These inefficiencies make sense because that’s how the food chain works. When we eat food, our bodies consume the calories, protein, and other nutrients needed to make sure we remain alive and ideally healthy. However, most of those ‘food elements’ aren’t really stored anywhere – they’re used. So if anyone tried to eat us, they wouldn’t get all the food elements we got when we ate our food.

The same is true for the animals/plants we eat. When eating a food, we only consume a part of the food elements that this food has received from its food [and so on]. So if we ate a cow for example, then we’d only be getting a small part of the food elements that it got from grass or feed. To avoid this inefficiency, we’d have to get lower on the food chain. This is the one of the main reasons why eating our ‘food’s food’ can reduce our impacts on the environment.

Other Important Sources of Emissions of High-Impact Foods

Unfortunately, it’s a bit more complicated than just the food chain. There are additional emission sources for different animals and farming practices – varying from enteric fermentation [methane generated during ruminant digestion], to aquaculture, and even manure. The graph below shows that cattle GHG emissions in low emission farms are primarily released by enteric fermentation. These ‘natural’ types of emissions are unavoidable, although they can be lowered through a variety of practices.

Reducing Food’s Impacts

There are plenty of policies and subsidies that governments can implement or remove to increase food security sustainably. As always, these types of large-scale solutions are the most effective ones. However, it’s important for individuals to understand that reducing the food system’s impacts is dependent on changing our unsustainable diets.

Transitioning toward animal-free diets can reduce the food industry’s land use by several million km2 by 2050, which can then help us restore green ecosystems worldwide. Additionally, phasing out animal products can lower the food system’s GHG emissions by up to 8.0 Gt of CO2e per year by 2050.

Evidently, heavier meat eaters can make the greatest changes in their diets – so developed countries have the highest potential for GHG emissions reductions. For reference, meat consumption per capita in the US is over 3 times the global average. However, it’s important to remain realistic. While there’s certainly an urgency to adopt more sustainable diets, not everyone can change their habits overnight – which is okay.

Apart from self-banning categories of foods, it’s quite hard for consumers to do more. One option would be purchasing foods that are labelled as ‘low-impact foods’, but current labelling standards often don’t provide this type of information. To allow individuals to make informed decisions, governments can enforce stronger labeling regulations on food products.

Quick Note

Some foods have been unsustainably produced in the past – but that doesn’t mean we should keep avoiding them now. For example, palm oil has been a driver of tropical deforestation for decades. However, it’s such a productive oil crop that replacing it with another type of oil could end up having a greater impact. This is especially true since many palm oil producers have now moved on to more sustainable practices.

In any case, looking for sustainability certifications for products that contain these types of ingredients remains important, to avoid buying from producers that haven’t switched to more sustainable practices.


Wastage, which comprises both food waste and food loss – has significant impacts on the environment. A few concerning factoids are listed below, as of 2013:

  • 1.3 billion tonnes of edible food are wasted or lost every year [13 billion pandas].
  • A third of all food produced for humans results in food wastage.
  • 250 km3 of freshwater are used to produce food that is either lost or wasted each year. For 8 billion people, that’s equivalent to over 85 liters of water per person per day [note that the WHO states that human basic needs are met with 50-100 L/day/person].
  • 28% of the Earth’s farmlands were used to produce food that is either lost or wasted.
  • $750 billion USD is lost per year due to food wastage, which is roughly the same amount as the GDP of Switzerland.

More recently, a 2021 UN report estimated that 931 million tonnes – or 17% – of all food available at consumer levels is wasted every year, mostly by individuals. That’s 9.31 billion pandas-worth of food per year, well over 1 panda per human every year.

The graph below shows one way to deal with food wastage.

Food Security

While one could think that reducing food wastage means reducing food production and thus food security – that’s not the case. Many regions of the world already suffer from food insecurity and hunger, although global wastage rates are high. Simply reducing food wastage by sharing food with the hungry would effectively increase global food security, while maintaining current global production if need be.

Nonetheless, it should be noted that completely eliminating global food wastage is neither a realistic nor desirable goal, since it would weaken global food security considerably.

It should also be noted that increasing meat production and consumption in select areas can have positive effects on local food security and ecosystems. However, this often isn’t the case, especially in developed countries where meat consumption levels are unsustainable and continue to strain the world’s remaining natural resources.


Governments can improve food systems swiftly at the largest scales by implementing better policies instead of placing the blame on consumers. However, unsustainable diets must change as well to reduce impacts and ensure long-term food security.

CyclopediApp isn’t here to tell you what to do or eat. That being said, if you’re willing to reduce your personal impacts on the environment and/or push for large scale change, then there are plenty of ‘food solutions’ waiting for you here.