homemade burger

What is sustainable food?

Sustainable food is the F in sustainably FED, the production, distribution and access for food is grown to supply the human population with 22 trillion kilocalories daily. A miraculous achievement, but can we keep it going?

Sustainable food is essential for feeding everyone well for as long as it takes. In this post, we go on a food journey not of culinary delights but of what it takes to grow, harvest, store and distribute enough food for 8 billion people and their pets—a story that will leak mindfulness into your day.

All humans have to eat. We can only exist without food for a week or two before our bodies begin to eat themselves. Because of this necessity, what we eat, when and how has always been central to individuals, groups and societies. 

Our success as a species owes much to our collaborative skills in finding, storing, cooking and sharing food from almost every place on Earth. Early humans learnt to eat whatever was edible in each habitat. They used their control of fire to cook and large brains to communicate and pass on knowledge of how to find and prepare edible foods.

Then we made a breakthrough by figuring out how to grow and rear food. The invention of agriculture just 12,000 years ago is staggeringly recent in the 300,000-year history of Homo sapiens and just a blink in the 6 to 7 million years since the first Hominids (great apes), but it meant we could persist in large groups, adopt a division of labour and create cultures with unimaginable technologies and complexity. It also allowed people to become much more numerous as farming technologies spread across the planet.

Then everything changed.

It is tempting to think that the invention of agriculture was pivotal in human history. It was a big deal that changed many things but wasn’t the most significant change.

The pivot came when humans made agriculture an energy sink.

Arguably two features of the industrial revolution, an adoption and an invention, changed agriculture. Humans have known about coal, oil and gas for a long time. We had electricity, steam engines, railways and steamships that had made a difference to food production. But the commercial extraction and use of oil in combustion engines from the early 1900s and the Haber-Bosch process to make fertiliser on an industrial scale using natural gas made food plentiful.

Oil and gas applied to agriculture was the change.

Almost overnight, farmers had machines to provide the labour to cut down vegetation, plough soil, fertilise fields and transport products to markets far and wide. They also had synthetic fertilisers to provide the nutrients. Agriculture went from an energy source to an energy sink and a food production powerhouse. Today food production is staggering across a dizzying array of commodities and volumes—2.7 billion tonnes of grains, 342 million t of meat, 154 million t fish—that are hard to picture. 

Dump just one tonne of grain in your living room and there is no room for the cat.

The addition of machines, fertiliser and pesticide inputs is called the intensification of agriculture. It increases yields and allows for economies of scale, but it turns food production into a net energy user and a business.

Global food production generates trillions of dollars in revenue because two out of three people buy at least some of their food from a store or a vendor. About a third of the global population still grows most of their food, but for over 5 billion people, their food supply comes via a marketplace.

In a few generations, modern humans created a technologically sophisticated, six-continent, just-in-time food supply chain that could feed everyone. 

Demand for food

The industrialisation or intensification of agriculture happened in a little over 100 years—the energy from fossil fuels went into food production and created a lot of food. 

As the farmers grew more food, the local and global trade flourished, and most of the time, most people in most places could find food.

And when plenty of food is available consistently, biology happens.

People ate this food and made more people.

Energy from fossils was converted into people—we eat and drink fossil fuels—and all of a sudden, billions of people exist, each needing around 2,000 kilocalories daily to power their bodies together with balanced nutrients to keep them healthy.

Collectively this creates a 22 trillion kilocalories a day challenge; the food energy needed to keep 8 billion people alive.

Today the demand for food is unprecedented in human history. 

No matter, people are tenacious and innovative and can sniff an opportunity from a thousand yards. Plus, there are fossil fuel slaves to help do the heavy work. Humans set about realising the opportunity offered by billions of consumers captured by the necessity of eating, and a global supply chain was built to profit from the chance.

Food supply. 

Food production happens on land and a little in the oceans, lakes and rivers. More specifically, it occurs in soil.

Soil is where seeds germinate, roots propagate, and go on to exchange water and nutrients with the growing plant. In the soil are billions of organisms of millions of types assisting with the nutrient and energy transfer to the plant. Almost all the food farmers grow depends on soil and the soil biodiversity that keeps soil healthy. Ask any farmer how easy it is to produce a crop in inert dirt, and he will laugh at you.

In the soil, the plants grow, capturing the sun’s energy via photosynthesis to reproduce. They must survive against competitors, disease, the weather, and any number of animals looking to eat them, but nature has equipped them well, and most of them make more, most of the time.

Agriculture is the channelling of what plants and animals do naturally—more making—into the parts of plants and animals that humans can eat. 

We eat the nutritious parts of the plant: the seeds, fruits, kernels, tubers and fleshy leaves. Then we feed the plants and plant parts that we cannot eat to animals, which convert the inedible parts into animal protein that is highly nutritious for humans. 

People are good at animal husbandry, choosing the animal species that produce well and yet are easily controlled. After a few thousand years of domestication, livestock makes up 97% of the land mammal biomass on earth today, the animals humans manage for our benefit. Animal protein is so important to us that we feed crops to cattle, sheep, goats and pigs. The 7 billion livestock animals in the United States consume five times as much grain as is consumed directly by the entire American population.

Collectively food supply has more or less, matched demand.

Food production happens on farms.

There are over 570 million farms worldwide. 

Farmers grow enough food on these farms to feed themselves, their livestock, and everyone else. 

Global food production is staggering.

Farmers not only grow enough food to feed everyone; they grow enough food globally for humans to waste a third of the output. Losses at harvest, transport, storage, processing, preparation and on the plate are more than enough to feed another 2 billion people.

Equal to this miracle of the global food supply is how food is grown and reared.

At least 2 billion people can feed themselves by growing their food. 

Five of every six farms of the 570 million farms are less than 2 ha in size. The farmers who work these smallholdings produce around one-third of the world’s crops, work hard, and tend to get higher farm productivity but lower labour productivity from their land. Many of these small farms operate on limited external inputs and use techniques of production honed over millennia to suit local soils, climates and technologies. We call these systems subsistence farming with the unwarranted assumption that it is inferior to industrial production.

Then there are the 6 million farms greater than 50 ha in size. These are almost all high-input, intensive agriculture farms, the 1% that operate more than 70% of the world’s farmland. Food production from these large enterprises feeds the people in the cities.

The UN estimates that by 2030, two out of three people, nearly 6 billion, will live in towns and cities. Most will have little or no opportunity to grow their food and rely on the complex, multi-continent food supply chain for sustenance.

Beyond these broad categories is layer after layer of nuance on what food can be grown, where and how? 

Food supply chain

Growing food is just the start. Getting food from the paddock to the plate is a complex and complicated sequence of actions and transactions—the food supply chain.

At the beginning of the chain are the farms and farmers growing the crops and rearing livestock, and at the end are retailers selling products to consumers. The multitude of exchanges along this supply chain introduces food economics, where food becomes commodities, the financing of production and distribution, and the financial risk associated with a volatile production and market system. 

Whilst there is money to be made in this most fundamental of transactions—remember everyone has to eat—the World Bank estimates the proportion of people involved in food production has declined globally from 44% as recently as 1991 to just 27% in 2019. In the OECD countries, this proportion is as low as 1%. 

As the human population grows, the proportion of people in agriculture declines. 

Proportional change is partly the consequence of large numbers, but the absolute number of agricultural workers has also declined. Farmers get the fossil fuel workforce to do all the heavy lifting and need fewer human workers. Infrastructure and technology reduce the need for intermediaries, especially as large corporations dominate the transactions along the supply chain.

The Pareto rule

This tale of agricultural production is not one of ever greater efficiency. Wherever food production happens, a range of efficiencies typically follows the 80:20 rule—that 80% of production comes from 20% of producers.

Not everywhere does food production make a profit, even in the more intensive systems. Many issues here, from investment, cost and farm debt to vested interests. It is not all smelling like roast pork on a Sunday lunchtime, not least the higher risks of simplified yet intensive production.

But at sustainable FED, we are interested in sustainable food—feeding everyone well for a long time—which brings us to another core concept.

Food security 

The fact that billions of humans alive today have food is a miracle of human ingenuity and the generosity of nature. 

Every day, food has to be present nearby and preferably in your pantry. 

The food you have must make sense for your culture, culinary skills, and stomach. And there is no point in there being times of plenty if next week, month or year, food is in short supply. 

Sustainable food is nutritious, healthy food supplied reliably.

The World Bank estimates although extreme poverty has declined, at least until the ravages of the COVID-19 pandemic, nearly half the world’s population—over 3.5 billion people—struggle to meet basic needs of food, clean air, water and shelter. They survive on less than $5.50 per day. 

Many of these people experience food insecurity.

It is not called food security by people who do not know where their next meal is coming from or might use over half their income to source food, but the concept can help us understand sustainable food.

There are four components of food security 

  1. availability
  2. access
  3. utilisation
  4. stability

Food must be present in your neighbourhood. You must be able to access that food by growing it or buying it. A kilo of rice is no help to you unless you have a stove and pan to cook it because the ability to utilise the food is just as crucial as having it. And then today’s meal is of little help if the food runs out in the future for one of the first three reasons.

These four pillars of food security apply to both calories and nutrients. A plentiful supply of rice and nothing else can keep a person alive for a long time until they succumb to illnesses of malnourishment. But as we discuss in our posts on sustainable diet, food security means enough food and nutrition for metabolic health.

The global numbers associated with food insecurity are sobering

  • 9% of the world’s population—700 million—has a caloric intake below minimum energy requirements.
  • 663 million people globally are undernourished.
  • 22% of children younger than five are ‘stunted’ due to poor nutrition or repeated infection.
  • One-in-four people globally—1.9 billion—are moderately or severely food insecure.

Something is wrong if enough food is grown, but 700 million people are starving, malnourished and food insecure. One or more of the components of food security have failed. 

In our posts on food production, Sustainably FED explores why the global food supply chain fails to deliver enough food to everyone where and when they need it. The truth is, on a global scale, we are not feeding everyone well. 

Abhorrent as this situation is, it is not the biggest problem. That dubious honour goes to the challenge presented by sustainable food.

What is sustainable food? 

Available, edible, nutritious and consistent.

What a person eats is the topic of our third theme, sustainable diet. 

Sustainable food is what the national and global populations eat via the local and global food supply chain. The key word is sustainable.

  • Is there enough food production to meet the demand? 
  • Can this production persist indefinitely? 
  • Can the supply chains deliver the food where it is needed? 
  • What happens if there are disruptions? 

And then there is the big question.

  • What happens when the fossil fuel energy subsidy to agriculture falters and ends?

Sustainable food production means growing food consistently well within ecological limits and not constrained by the need for nutrient and energy inputs, especially when those inputs come from fossil fuels. 

Think about this for a moment.

Australia is famous for its sheep. Even today, more than 70 million sheep are grazing across the dry continent, producing wool and meat. In 2021, this national flock converted grass into 345,000 tonnes of wool that contained roughly 86,250 tonnes of nitrogen. In 2023 the national flock also delivered 740,000 tonnes of meat, over half of which was exported. That is another 74,000 tonnes of nitrogen that left the paddocks.

Removing that much of a critical nutrient from the soil is not sustainable. The only way for production to continue is if the farmers apply fertilisers to replace the nitrogen.

Mining is only sustainable if there is an infinite resource being extracted. Nitrogen in soil is far from infinite, so farming practices have to return the nitrogen for production to be sustainable. 

The same logic applies to all the other nutrients and the soil carbon.

Sustainable food is not a type; it is a reflection of the production system.  There will always be any number of production methods and many can be sustainable with efficient use of ecological principles, what we call food ecology. Indeed there are nearly as many systems of production as there are producers. 

There is no one sustainable food, no one size to fit all. In short, sustainable food is all about food ecology and context.

For sustainably FED sustainable food is understood scientifically, is flexible, and works with the constraints of the producer and the production environment. 

Sustainable food is also about

  • what kind of food is produced—the nutrient density and calorific content determine the quality of the collective diet. This is as much about what is grown as it is about demand.
  • accessibility—there is no point in producing food at $10 a kilo if half the population cannot afford to buy it. Good food must therefore meet demand equitably. This is about price but also about availability and distribution.
  • the 80:20 rule to benefit the 20% of producers who are getting it right and delivering 80% of the food supply. It should also get some of the 80% of weaker producers up to speed.
  • Variety because humans need variety for a sustainable diet but also because variety can deliver redundancy and resilience in production and food supply.
fresh vegetables set out for a banquet showing variety, the. key feature of sustainable food

The size of the sustainable food challenge.

Achieving these definitions of sustainable food is a vast undertaking. 

So far, humanity has delivered a miracle to keep up with our own numerical and economic success. We have met a staggering increase in demand for food through intensification and the industrialisation of complex supply chains run on fossil energy. Only this is just the beginning.

We already know that future food security will mean at least 22 trillion kilocalories a day for another 100 years—sustaining this level of food production will be another miraculous achievement.

It will require an ecological focus even in the intensive systems of developed and emerging economies. And like many issues we explore on sustainably FED, there is no one answer.

How long will it take?

At the start of this post, we asserted that sustainable food is essential for feeding everyone well for as long as it takes. 

How long is that?

The global population of 8 billion people is still increasing at 8,000 per hour. This time tomorrow, the number of people on the planet will have risen by 192,000 and next week by 1.34 million extra people.

In a year hence, barring major global catastrophe, there will be 70 million extra people, nearly double the number of Canadians.

Numerically, the challenge just gets bigger.

Global economic growth is a prickly subject but everyone projects growth. This means more people with money to buy more energy and nutrient-dense food—the staggering growth in pork consumption in China is a classic example.

Demographers tell us there is a transition that the human population could pass through to lower overall numbers as this extra wealth slows reproductive rates down to less than two children per woman—the best explanation of this transition comes from the late, great Hans Rosling.

But this will take at least 100 years, perhaps longer. Meantime there are people to feed.

It is sobering to remember that the fossil fuel pulse will not last this long.

The challenge could be cut drastically by collapse. But then, by definition, sustainable food will have failed.

What sustainably FED suggests…

Our concept of sustainable food production requires concerted effort, radical change, and evidence.

We believe that knowledge of food’s demand and supply side needs to be spread widely, especially the role of the ecological engine that allows farmers to grow food.

Science needs to tell us how the ecological engine works. What fuel does it need? What is its optimal and repeatable running temperature? And when will the engine reach its local and global limits?

Knowledge can be distilled to provide producers with the evidence to make smarter production decisions from the smallholding to the large commercial properties. It can help investors with their returns and help policymakers design rules to help feed everyone.

Current vested interests and a profit-driven production system will not take us beyond 2050; the trajectories are in the wrong direction. New financial instruments that prioritise long-term production over short-term profits are just one of the many options.

Food production must happen for a long time to come. So we also need to know what happened in the past to predict what future food production will look like.

No other organism has appropriated nature to feed itself as humans now do.

We have converted the landscape for agriculture, diverted the freshwater, mined the earth, fished the oceans, reduced global biodiversity, and even messed with the climate. At least a third of historical and current greenhouse gas emissions result from agricultural production.

These global changes happened to feed people who made more people.

Today this numerical, technological and economic success presents the biggest challenge humans have ever had to face. How to feed everyone well.

Fail and humanity will collapse.

If this concept grabs you, please browse around the sustainable FED site for more information and ideas on sustainable food, food ecology and sustainable diet

sustainably FED

Hero image modified from photo by Lidye on Unsplash


Mark is an ecology nerd who was cursed with an entrepreneurial gene and a big picture view making him a rare beast, uncomfortable in the ivory towers and the disconnected silos of the public service. Despite this he has made it through a 40+ year career as a scientist and for some unknown reason still likes to read scientific papers.

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