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Foundations of Sustainable Agri‑food Systems & the Circular Economy

Redesigning food systems to reduce waste and regenerate natural resources, for a more resilient and regenerative future for people and the planet.

Lab to Farm

Where Science Grows Solutions & Innovation Meets Sustainability

Follow our movement

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Lesson A – Why Food Systems Matter: Planetary Boundaries & SDGs

Remember: The three pillars of sustainable food systems (People, Planet, Profit) and define the concept of planetary boundaries
Explain: How food systems impact multiple planetary boundaries and contribute to crossing safe environmental limits
Apply: Use a common meal as an example to identify how food systems connect to specific Sustainable Development Goals (SDGs)
Analyze: How food system activities influence multiple planetary boundaries, and explain how these environmental limits interact with social and economic goals

Lesson B – From Linear to Circular: Rethinking Food Production

Apply: Identify linear and circular food system features using real-world agri-food examples from case studies
Analyze: Compare real-world case studies of waste-to-resource solutions by identifying what waste is used, what new products are made, and how the process helps the environment
Evaluate: Assess trade-offs among case study pathways considering scalability, economic value, and nutrient recovery potential

Lesson C – Pathways to Action: Diet, Innovation & Policy

Apply: Use provided data and tools to compare the environmental impacts of different food choices (e.g., beef vs. beans) in terms of CO₂e, water use, and land use
Create: Develop an action plan that combines at least one personal, one entrepreneurial, and one policy solution to advance a more sustainable and circular food system in your community
Evaluate: Justify your innovation’s feasibility, projected environmental benefits, and potential social or economic co-benefits in a short peer pitch
Analyze: Compare the strengths and limitations of diet, innovation, and policy pathways, and explain how they can work together to drive systemic change

Sustainable Agri-Food Systems and Circular Economy

Module 1: Foundations of Sustainable Agri-Food Systems and Circular Economy

SLIDE 2 Spoken Dialogue:

“Here’s our roadmap: Lesson A – Why Food Systems Matter: We’ll connect planetary boundaries and the UN Sustainable Development Goals to agriculture and food production. Lesson B – From Linear to Circular: We’ll explore how to redesign food systems to be restorative and regenerative. Lesson C – Pathways to Action: We’ll discuss solutions from individual choices to global policies. By the end, you’ll see how these lessons fit together to give us a systems-level understanding of food.” Key Points to Emphasize: The module has three lessons, each building on the previous one. Students will engage with activities, case studies, and discussions in each lesson. By the end, they should see the interconnections between environmental, social, and economic dimensions of food systems. Facilitation Tips: Read the lesson titles aloud. For each, give a 1–2 sentence summary and link to real-world contexts. Let students know that these lessons will prepare them for future modules where they apply the concepts in more technical and practical ways.”

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How can we design food systems that respect planetary limits while advancing global well-being?

Lesson A – Why Food Systems Matter: Planetary Boundaries & SDGs

SLIDE 3 Spoken Dialogue:

“Throughout this module, we’ll keep coming back to one essential question: How can food systems respect planetary limits while improving lives? To start, think about why food systems matter for the future of both people and the planet — food isn’t just calories, it’s tied to health, climate, jobs, land, and culture. For people, it connects to fair wages, nutrition, and access; for the planet, it’s about land, water, biodiversity, and emissions; and for profit, it’s about keeping farming and food affordable and viable. The key is balance — food systems only work when People, Planet, and Profit overlap. To see this in action, we’ll do a quick activity: write one word under ‘People,’ ‘Planet,’ or ‘Profit’ that food impacts most, and together we’ll look at the patterns and where these pillars intersect.”

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A sustainable food system delivers nutritious food for all in ways that sustain—and strengthen—the environmental, economic, and social foundations
Ensures food security now and for future generations.

Sustainable Food Systems

Warner, 2013

SLIDE 4 Spoken Dialogue:

“A sustainable food system isn’t just about the food on your plate — it’s about making sure food is produced, distributed, and consumed in ways that support people, protect the planet, and remain economically viable. If even one of those pillars is missing — social, environmental, or economic — the system becomes unstable. When you hear the word ‘sustainable,’ what comes to mind? Maybe recycling, renewable energy, or saving resources. Now, think about food: a sustainable system feeds everyone today with safe, healthy, affordable meals while protecting our ability to feed people tomorrow by caring for soils, water, farmers, and ecosystems. To test this, let’s take your favorite meal — pizza, burgers, sushi, anything — and ask: Does it meet the People, Planet, Profit test? Does it feed people fairly, respect the environment, and stay affordable for farmers and consumers?”

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The 3 Pillars (3 Ps)

People (social well-being)
Planet (environmental health)
Profit (economic viability)

Food for Thought

Imagine a food system where one of these pillars is ignored.
What consequences could arise?

The 3 Pillars of Sustainable Food Systems

Riley J.P. et al., 2015

SLIDE 5 Spoken Dialogue:

“Sustainable food systems rest on three interconnected foundations — People, Planet, and Profit — and true sustainability means balancing all three. People is about fairness, nutrition, and well-being; Planet is about protecting soil, water, climate, and biodiversity; and Profit is about keeping farms and businesses economically viable. If one pillar is missing, the system eventually fails — for example, chasing Profit without protecting Planet depletes resources, or prioritizing People and Planet without Profit makes farming financially impossible. To see this in action, in small groups imagine a food system where one P is missing and discuss 1–2 real-world consequences — then we’ll share a few examples together. The key takeaway: sustainability only works when People, Planet, and Profit stay in balance.”

Figure from Tedeschi, L., Muir, J.P., Riley, D.G. and Fox, D.G., 2015, July. Future implications for animal production: a perspective on sustainable livestock intensification. In Proceedings of the 52nd Annual Meeting of the Brazilian Society of Animal Science.

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Planetary Boundaries: Earth’s Safe Space

What Are Planetary Boundaries?

Defines 9 planetary thresholds humanity must stay within for a stable Earth system.

Current Status

6 of 9 boundaries have been crossed, including climate change, biosphere integrity, biogeochemical flows (N & P), land-system change, freshwater change, and novel entities.

Food Systems’ Role

How we produce and eat food is pushing Earth past its safe , especially through nutrient pollution, land conversion, and biodiversity loss.

Source: Planetary Health Check 2025

SLIDE 6 Spoken Dialogue:

“The planetary boundaries framework shows us the limits we need to stay within for Earth to remain stable and habitable — things like climate, biodiversity, land use, freshwater, and nutrient cycles. Scientists warn that 6 of the 9 boundaries have already been crossed, and food systems are a big driver: farming and ranching release major emissions, cropland expansion destroys habitats, and fertilizer overuse pollutes water with nitrogen and phosphorus, creating dead zones. For example, the same nitrogen that boosts crop yields can wash into rivers and fuel algae blooms that kill fish. The key idea is that our food choices are directly linked to these overshoots — but if we redesign food systems, we can also help pull back into Earth’s safe space. To make it personal, let’s look at the planetary boundaries diagram and ask: which boundary do you think your lunch impacts most?”

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(Richardson et al 2023)

Half of Earth’s green land = crops & pasture
~25 % of global Greenhouse Gases (GHG)

→ farm to your fork

#1 cause of deforestation & habitat loss

→ biodiversity crash

N & P (nitrogen, phosphorus) overload

→ dead zones, algae blooms

Food Systems = Massive Footprint

IMAGE: Radar charts show food maxing out land‑system change, nutrient cycles, biosphere integrity

Each spoke represents one of the nine critical Earth-system processes. The closer the colored wedge extends toward the outer edge, the more that boundary has been exceeded.

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Cheeseburger Check‑Up:

What do a bun, patty, and slice of cheese have to do with the UN’s Sustainable Development Goals?

17 Goals

1 Plate

Sustainable Development Goals (SDGs) form a roadmap to end poverty, protect the planet, and ensure prosperity and equality by 2030

→ Food Systems Are at the Heart of Change

Every Bite Counts: Sustainable Development Goals

Penthes, 2018

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Every Bite Counts: Sustainable Development Goals

Singh, 2023

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The Burger Supply‑Chain Footprint

Agriculture: farmer incomes, cropland, pasture use
Water: thirsty feed crops & cattle drinking needs
Energy + Transport: tractors, trucks, cold‑chains → CO₂ emissions

Inequalities: who can afford healthy food? wage gaps along the chain
Climate: cows belch methane (CH₄) → potent greenhouse gas
Ecosystems: ranching can encroach on forests, shrinking wildlife habitat

Kiger, 2025

The Burger Supply Food Chain

SLIDE 10 Spoken Dialogue:

“A burger isn’t just a patty on a bun — it represents an entire supply chain of farming, water, energy, labor, and ecosystems. Wheat is grown for the bun, soy and corn are grown to feed cattle, and the cattle themselves require vast amounts of water and land while producing methane, a powerful greenhouse gas. Trucks, tractors, and cold storage all use fossil fuels, adding more emissions, while ranching often replaces forests and reduces biodiversity. Along the way, wages and profits are uneven, from farmworkers to fast-food employees, and access to healthy alternatives remains unequal. Even one burger carries a global footprint — but multiplied by billions, the impact is enormous. To test your understanding, let’s do a quick poll: which part of a burger has the biggest environmental footprint — the bun, the cheese, or the beef?”

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Food and the circular economy

Key Message:

Redesigning our food system boosts many SDGs at once—that’s why the United Nations and governments worldwide call sustainable agri‑food the KEY to the 2030 Agenda!

Sustainable [food] Development Goals (SDGs) = Bites That Build a Better World

Penthes, 2018

Gausa, 2024

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Let’s talk about the “Double the Food” Claim

The Scare Line: “We must double food by 2050 to feed 10 billion!”
Default reaction = more mega‑farms, chemicals, land‑clearing
But… is it true? Let’s bust the myth

DOUBLE FOOD BY 2050!

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2050 pop ≈ 9.8 B

→ more mouths & higher incomes

Meat demand ~70 % vs 2010
Total calories needed ≈ +50 % (not 100 %)
Myth assumes no change in waste or diets

→ linear thinking, is getting us in trouble!

and

What Demand Really Looks Like

Ranganathan, 2018

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Current output ≈ 1.5× what 10 billion people require
1/3 of food is lost or wasted
Grain → livestock = energy drain
100 cal grain → 3 cal beef → 12 cal chicken, 22 cal eggs

Huge inefficiency hides in our plates, not our fields!

We Already Grow Enough Calories!

Adelaide, 2025

SLIDE 14 Spoken Dialogue:

“The truth is, the world doesn’t face a food production crisis — it faces a food system crisis. Globally, we already grow about one and a half times more calories than what 10 billion people would need, but so much is wasted, misused, or unevenly distributed that hunger persists. Roughly a third of all food is lost along the supply chain, and much of the grain we do grow gets fed to livestock — where 100 calories of grain may return only 3 as beef, 12 as chicken, or 22 as eggs. At the same time, some communities suffer food insecurity while others overconsume and waste. The real challenge isn’t producing more but managing food more wisely — cutting waste, rethinking diets, and ensuring access — so we can feed the future without pushing past planetary limits.”

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Cut waste: save farm‑to‑fork losses
Shift diets: more plants, less red meat → land, water, GHG wins
Study shows these two levers could feed billions without plowing new land
Produce smarter & Consume smarter = real solution

We Already Grow Enough Calories!

Barimah, 2021

SLIDE 15 Spoken Dialogue:

“The real solution isn’t just to produce more food, but to produce and consume smarter. We already grow enough calories to feed everyone — the real challenge is what happens between the farm and the fork. Roughly a third of food is lost or wasted, whether it’s spoiled during storage and transport in regions with weak infrastructure, or thrown away by consumers in wealthier countries. At the same time, a large share of crops goes into inefficient uses like livestock feed, where many calories are lost in conversion to meat. By tackling waste and shifting diets toward more plant-based foods, we could free up land, cut greenhouse gases, and protect ecosystems, all while feeding billions more people without clearing new farmland or overloading the planet’s resources.”

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Would clear most remaining forests → biodiversity crash
Turbo‑charges GHGs

→ climate spiral

Doesn’t solve hunger or nutrition gaps

Better Path: regenerative farming + circular economy + diet & waste action

Transform the system, not just crank it up!

Why “Double the Old Way” = Disaster

ChatGPT

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Review Questions

What are the 3 Pillars of a sustainable food system, and why must all three be considered when making agricultural decisions?
Which planetary boundaries have been most affected by modern food systems, and how do these impacts threaten environmental stability?
What’s the flaw in the claim that we must double food production by 2050, and what smarter alternatives can reduce pressure on ecosystems?

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Review Answers

People (social well-being), Planet (environmental health), and Profit (economic viability) must work together — ignoring any pillar risks food insecurity, ecosystem damage, or economic collapse.
Modern food systems drive overshoot in climate change, biodiversity loss, nutrient pollution, land-use change, freshwater use, and novel entities — destabilizing Earth’s safe operating space.
We already produce ~1.5× needed calories; waste and diet inefficiencies inflate demand. Cutting loss, shifting diets, and farming smarter can feed billions without expanding farmland.

SLIDE 18 Spoken Dialogue:

“The three pillars of a sustainable food system are People, Planet, and Profit — and all must work together, because ignoring even one risks food insecurity, ecosystem damage, or economic collapse. Modern food systems are also responsible for pushing several planetary boundaries past safe limits, including climate change, biodiversity loss, nutrient pollution, land-use change, freshwater depletion, and novel entities like plastics — all of which destabilize Earth’s systems. Finally, the idea that we must double food production by 2050 is flawed, since we already produce about one and a half times the calories needed; the real issue is waste and diet inefficiencies. Smarter alternatives like cutting food loss, shifting diets, and farming in regenerative ways can feed billions more without clearing additional land.”

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How can we redesign food systems so nothing goes to waste?

Lesson B – From Linear to Circular: Rethinking Food Production

SLIDE 19 Spoken Dialogue:

“Lesson B challenges us to rethink food production — instead of asking how we grow more, we ask how we grow smarter so nothing goes to waste. Right now, most food systems are linear: resources go in, products come out, and waste piles up, leaving behind lost nutrients, pollution, and degraded ecosystems. But nature doesn’t work this way — in a forest, everything cycles back, with waste becoming the next input. Our challenge is to design food systems that work more like ecosystems: where food scraps become compost, nutrients return to the soil, packaging is reused or biodegradable, and farming restores rather than depletes. This is the idea of a circular economy — shifting from ‘take, make, waste’ to ‘reuse, recycle, regenerate.’ Done right, it cuts pollution and emissions, protects forests and biodiversity, and builds resilience by reusing what we already have.”

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We TAKE: Tap soil nutrients, pump irrigation, burn fuel
We MAKE: Turn them into burgers, smoothies, plastic wraps
We WASTE: Scraps rot, runoff pollutes, packaging hits landfill
A one‑way street to the dump: Resources out, pollution up, nothing cycles back

Linear path — “take → make → waste”

From Linear to Circular: Rethinking Food Production

Munjur et al., 2018

SLIDE 20 Spoken Dialogue:

“A linear food system works like a one-way street — we take, we make, and we waste. We extract soil nutrients, pump water, and burn fossil fuels to grow and process food; we transform those resources into burgers, snacks, and packaging; and then we throw away scraps, plastic, and nutrients that could have been recycled. The result is pollution in our air, soil, and water, greenhouse gases from livestock and landfills, and lost nutrients that weaken ecosystems. This ‘take–make–waste’ treadmill treats food as if it exists outside of nature’s cycles, but ecosystems don’t work that way — in a forest, leaves become soil, and in rivers, decay fuels new life. Our current linear model breaks those natural loops, leaving us with more waste and fewer resources. The challenge ahead is how to redesign food systems so they mimic nature’s cycles instead of fighting against them.”

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6 garbage trucks of edible food wasted every second
Cities recover < 2 % of food nutrients → the rest is burned or buried
Front‑end pumps in synthetic fertilizers & mined minerals

Clearly ripe for disruption!

The Waste Meter

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Mimic nature’s loops → “waste” becomes input
Organics kept toxin‑free → compost & fertilise soil
Nutrients circulate → materials stay in use

A Circular Economy - designing and running our economy to eliminate waste, keep materials in use, and regenerate natural systems instead of depleting them.

Enter the Circular Economy

Munjur et al., 2018

SLIDE 22 Spoken Dialogue:

“The circular economy flips our current food system on its head by turning waste into opportunity and designing loops that mimic nature. Instead of the linear model of ‘take, make, waste,’ a circular food system works like a forest — where leaves decompose to feed new growth and nothing is thrown away. In practice, that means keeping food scraps and manure toxin-free so they can be composted, cycling nutrients like nitrogen and phosphorus back into soils instead of letting them pollute rivers, and reusing or recycling packaging and materials. The result is fewer landfills, lower emissions, healthier soils and ecosystems, and more resilient food systems that regenerate rather than deplete. In short, circular means ‘cycle, regenerate, reuse’ — every output becomes a new input.”

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Food scraps are not waste. Instead: compost, biogas, or feed in a circular system
By‑products like fruit pulp or cooking oil can be repurposed into bioplastics or biodiesel

Image: “The Butterfly” – 2 Material Loops:

(Right) Biological materials go back to nature through composting / digestion.
(Left) Technical materials remain in use via repair, reuse, or recycling.

Circular Economy in Action: Turning Waste Into Value

SLIDE 23 Spoken Dialogue:

“In a circular food system, waste is no longer waste — it’s raw material for the next cycle. Food scraps can become compost to enrich soils, biogas to generate renewable energy, or even animal feed, while by-products like fruit pulp can be transformed into bioplastics and used cooking oil can be turned into biodiesel. The circular model has two loops: the biological cycle, where organics like food and paper safely return to nature through composting or anaerobic digestion, and the technical cycle, where durable materials like plastics or metals are reused, repaired, or recycled instead of discarded. This approach keeps organic waste out of landfills, reduces methane emissions, cuts demand for new raw materials, and creates new economic opportunities — all while restoring ecosystems by putting nutrients back into the soil.”

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Closed loop food system: nutrients & materials keep cycling
Powered by renewables, building healthier soil, water, biodiversity
“Waste not, want not” → redesign the system, don’t just manage trash!

5 Rs: Reduce – Reuse – Recycle – Refurbish – Regenerate

The 5 Rs: Key Principles of Circularity

Munjur et al., 2018

SLIDE 24 Spoken Dialogue:

“The 5 Rs capture how we move from waste management to true system redesign: Reduce, Reuse, Recycle, Refurbish, and Regenerate. In a circular food system, that means cutting inputs like fertilizer or packaging, keeping products in circulation through reuse, recycling materials like plastics or paper, extending the life of tools and equipment through repair, and most importantly, regenerating soils, water cycles, and biodiversity so ecosystems actually improve over time. Together, these principles create a closed-loop where nutrients and materials keep flowing, farms are powered by renewables, and ecosystems are restored as an outcome rather than an afterthought. The big shift is this: instead of asking how to manage waste after it’s made, we redesign the system so waste never appears in the first place.”

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Agroecology: Ecological approach to farming that treats the farm as a living ecosystem

Crop diversity, nutrient cycling, natural pest control)

Regenerative Agriculture: Farming methods that go beyond sustainability to restore and improve soil health, water cycles, and biodiversity

Leaves the land better each year

Rethinking Farming with Nature

Agroecology & Regenerative Agriculture = Nature-Powered Farming

Tittonell et al. 2022

SLIDE 25 Spoken Dialogue:

“Industrial farming often runs like a factory, with fertilizers, pesticides, and fuel going in and crops or livestock coming out — but this approach weakens soils, pollutes water, and drains ecosystems. Agroecology and regenerative agriculture flip the script by treating farms as living ecosystems that work with nature instead of against it. Agroecology applies ecological principles — planting diverse crops for resilience, recycling organic matter for soil fertility, and using natural pest control — while regenerative agriculture goes a step further, aiming to leave the land better each year by rebuilding soils, repairing water cycles, and boosting biodiversity. Together, they show us that farming can be more than just producing food; it can actively restore ecosystems and build resilience in the face of climate change.”

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A: Crop rotation & cover crops→ soil shield & nutrient bank

B: Livestock + crops → manure fertilizer loop

C: Compost & biocontrol instead of chemicals

D: Polycultures → resilience & natural pest breaks

Goal: a self‑regenerating mini circular system on every farm!

Agroecology in Action

A

B

C

D

SLIDE 26 Spoken Dialogue:

“Agroecology turns theory into practice by designing farms that function like ecosystems — cycling nutrients, supporting biodiversity, and restoring soil and water. Farmers use crop rotation and cover crops to keep soils fertile and protected, and they integrate livestock with crops so manure becomes a resource rather than waste. Composting food scraps and crop residues replaces synthetic fertilizers, while beneficial insects or microbes reduce the need for chemical pesticides. Polycultures — growing several crops together — boost biodiversity and resilience so that if one crop fails, others can still thrive. Each of these practices creates loops that keep resources cycling, and together they transform a farm into a self-regenerating system that produces food while improving the land.”

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Regenerative Farming in Action

Build Soil Carbon → locks away CO₂ and feeds microbes
Improve Water Cycles → sponge-like soil buffers drought
Restore Ecosystems → pollinators + wildlife thrive
Managed Grazing → mimics wild herds, revives grasslands

Regenerative agriculture goes beyond sustainability – it restores ecosystems, improves soil, and builds resilience.

SLIDE 27 Spoken Dialogue:

“Regenerative farming shows that agriculture doesn’t have to harm ecosystems — it can actually heal them. The goal isn’t just to sustain but to improve the land every year. Practices like building soil carbon lock away CO₂ and create rich, living soils; improving water cycles turns farms into sponges that absorb rain and resist droughts and floods; restoring ecosystems with hedgerows, cover crops, and wildflower strips supports pollinators and biodiversity; and managed grazing, where livestock rotate across pastures, revives grasslands instead of exhausting them. Together, these practices rebuild the foundations of food production — soil, water, and ecosystems — making farms healthier and more resilient. As we watch the video, notice how these techniques flip the usual story: instead of depleting land, regenerative agriculture restores it.”

Visual / Media Integration: Regenerative agriculture in action: Wood Farm, Wiltshire

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Ellen Macarthur, 2019

Cut External Inputs

Reduce synthetic fertilizers & pesticides
Where Waste can = a Resource
Manure, husks are reused in the system

Farmers in the Driver’s Seat

Local solutions, not one-size-fits-all

Long-Term Sustainability

Closed-loop systems support soil, water & communities over time

Less waste, fewer inputs, more resilience

Circular Economy + Nature-Based Solutions = Perfect Loop

SLIDE 28 Spoken Dialogue:

“The real breakthrough happens when circular economy principles and nature-based farming come together — that’s when the perfect loop emerges. Circular design eliminates waste, keeps resources cycling, and regenerates natural systems, while practices like agroecology and regenerative farming restore soils, water, and biodiversity. In this model, waste becomes a resource — manure, crop husks, and food scraps turn into compost, fertilizer, or even energy — and reliance on costly synthetic inputs is reduced. Farmers take the lead by applying ecological knowledge to their own land instead of being locked into one-size-fits-all solutions. The result is long-term resilience: healthier soils, cleaner water, empowered communities, and food systems strong enough to withstand climate and market shocks. When circular design meets nature-based solutions, we get food systems that waste less, restore more, and thrive over time.”

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The Combo Framework

Experts say, “we need to combine circular economy innovation with agroecological principles.” Let’s recap why…

Regenerative Agriculture restores soil, water, and biodiversity through land-based practices
Agroecology applies ecological science + local knowledge to redesign farming systems
Circular Economy keeps resources flowing—eliminates waste, maximizes reuse

Together → Transform food systems from factories into ecosystems

Healthier land = More productive, year after year

SLIDE 29 Spoken Dialogue:

“The combo framework reminds us that no single approach can fix food systems on its own — the real power comes from combining regenerative agriculture, agroecology, and circular economy. Regenerative practices rebuild soils, restore water cycles, and bring back biodiversity so land grows healthier each year. Agroecology applies ecological science and local knowledge, treating farms as ecosystems with diverse crops, nutrient cycling, and farmer-led solutions adapted to place. Circular economy design closes the loop, eliminating waste and keeping resources in use through reuse, recycling, and regeneration. Together, these approaches flip the system from one that extracts and discards to one that renews and regenerates — producing more food on healthier land, with stronger ecosystems and more resilient communities.”

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Valorization of Food Waste as Animal Feed: A Step towards Sustainable Food Waste Management and Circular Bioeconomy - PMC

Old way:

peels rot → methane

New loop:

peels (dry and mill)

→ high‑fiber cattle pellets

Cuts landfill waste & methane
Replaces pricey grain for ranchers = win‑win

Case Study: Sicily’s Citrus Super-Loop

Citrus Peel → Cattle Feed

Upcycled Animal Feed: Sustainable Solution to Orange Peels Waste

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Kumar et al. 2025

Essential oils extracted first (perfume, cleaning products)
Leftover pulp → animal feed & biogas energy
Regional waste turned into revenue & renewable power—a full circular chain!

Case Study: Sicily’s Citrus Super-Loop

SLIDE 31 Spoken Dialogue:

“Sicily’s citrus super-loop shows how one crop can be transformed into multiple valuable products instead of producing waste. From the same peel, processors extract essential oils for perfumes, cleaning products, and flavorings, then dry the leftover pulp into nutritious animal feed pellets for ranchers, and even feed residues into anaerobic digesters to produce renewable biogas. The result is a near-zero waste system where every part of the citrus fruit has a purpose. This circular chain cuts waste, creates new revenue streams, supports local ranchers with cheaper feed, and generates clean energy for communities. It’s a powerful example of how regional waste can be turned into regional value — making food systems both more sustainable and more profitable.”

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Strickler, 2022

Distilleries' Spent Grains as a Great Way to Raise Fungi

Distillery grain surplus → cost & odor problem
Researchers grow oyster mushrooms on it
Gourmet mushrooms fetch $15‑25/lb → new income stream
Post‑harvest substrate still feeds livestock or composts → zero waste

Case Study: Spent Grain to “Bourbon Shrooms”

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Distillery saves disposal fees
Local growers gain a free substrate
Extra protein & flavour added to grain leftovers
Another nutrient loop closes—waste → food → soil

Case Study: Spent Grain to “Bourbon Shrooms”

Community Wins from Mushrooms

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Circular mindset = opportunity factory

A: Bakeries send stale bread to breweries → craft beer

B: Farms run biogas digesters → electricity + liquid fertilizer

C: Ugly produce upcycled into juice & snacks

D: Cities collect food scraps → compost for urban gardens

Endless Loop Idea

A

D

B

C

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Ellen Macarthur, 2019

Circular food could unlock $2.7 T by 2050
Cuts the hidden $2 of damage for every $1 we spend on food
Brainstorm activity: list your school’s by‑products & invent one circular use for each! Who will find the next citrus‑peel or grain‑mushroom solution? Get creative!

Big Payoff & Your Turn

SLIDE 35 Spoken Dialogue:

“The payoff from circular food systems is huge — globally, they could unlock $2.7 trillion a year by 2050 while slashing the hidden costs of food, like soil depletion, polluted water, climate damage, and health care expenses. Farmers save money by reusing resources, communities benefit from cleaner water and healthier diets, and new local businesses can emerge from what used to be waste. But the real innovation starts right here — in our own school. Think about the by-products around us: cafeteria scraps, orange peels, leftover cooking oil, or even landscaping waste. In small groups, brainstorm one creative circular use for each — maybe compost for the school garden, biodiesel for buses, or natural cleaning products. Who can come up with the most inventive idea — the next citrus peel or grain-to-mushroom solution?”

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How does nature demonstrate that resources can be reused endlessly with no waste?
What framework defines the environmental limits humanity must stay within to ensure a stable Earth system?
What way of thinking helps us connect our food system choices to environmental and social impacts?

Review Questions

SLIDE 36 Spoken Dialogue:

“Let’s close with a quick review. First, how does nature show us that resources can be reused endlessly without waste? In ecosystems, everything cycles — leaves decompose into soil, one organism’s waste becomes another’s food, and nutrients circulate again and again, making nature the ultimate circular system. Second, what framework defines the environmental limits humanity must stay within to keep Earth stable? That’s the Planetary Boundaries framework, which identifies nine critical thresholds like climate, biodiversity, and nutrient cycles that mark our ‘safe operating space.’ Finally, what way of thinking helps us connect our food choices to environmental and social impacts? Systems thinking — the practice of seeing relationships and ripple effects, not just isolated parts, so we can understand how diets, waste, farming, and policies all connect.”

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Review Answers

Through circular cycles like nutrient loops, where one organism’s waste becomes another’s resource: the model for a Circular Economy.
The Planetary Boundaries framework: Nine critical Earth-system limits we must not exceed to maintain a safe operating space.
Systems thinking and the Triple Bottom Line, considering People, Planet, and Profit together in decision-making.

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Is there a single most powerful change — on your plate, in a business, or in law — that could make our food system more sustainable?

Lesson C - Paths to Action: Diet, Innovation, Policy

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Three interconnected pathways can drive meaningful transformation in the food system:

Dietary Shifts: Align consumption with environmental limits and public health
Innovation: Redesign production and supply chains to reduce waste and regenerate resources
Policy: Enact regulations, incentives, and investments that enable sustainable practices

Pathways to Action

SLIDE 39 Spoken Dialogue:

“Diet, innovation, and policy are the three levers that can reshape food systems, and while each has power on its own, together they drive the biggest change. Dietary shifts — like eating more plant-based meals, cutting back on red meat, and reducing food waste — ease pressure on land, water, and emissions while improving health. Innovation redesigns production and supply chains, from upcycling by-products and scaling regenerative farming to using renewable energy and compostable packaging. Policy sets the rules of the game through subsidies, bans, and investments that make sustainable practices the norm. When diet creates demand, innovation supplies solutions, and policy scales them up, the three reinforce each other — and that’s how we create lasting, systemic transformation.”

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Dietary Shifts: Beef VS. Beans

SLIDE 40 Spoken Dialogue:

“The beef versus beans comparison shows just how powerful dietary shifts can be. Producing beef takes huge amounts of land, water, and energy, and releases methane — a greenhouse gas far stronger than CO₂ — while beans provide similar protein with only a fraction of the resources and emissions. This simple example proves that even small changes in what we eat can have a big impact on climate, biodiversity, and public health. To see how redesigning diets and food products can create ripple effects across people and planet, we’ll watch a short video, The Story of the Big Food Redesign. As you watch, keep this question in mind: How can redesigning what we eat reduce waste and regenerate resources? Afterward, we’ll share one surprising fact or connection you noticed.”

Video Integration: The Story of The Big Food Redesign

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Cattle use ⅔ of all agriculture land but give ≈ 3 % of global calories
Beef = 10–20× CO₂‑e (emissions) per gram protein vs. beans
Cutting red meat = top personal climate action

Ranganathan et a l 2016

Dietary Shifts: Beef VS. Beans

Why It Matters

SLIDE 41 Spoken Dialogue:

“The beef versus beans comparison makes the math clear: cattle take up about two-thirds of all agricultural land worldwide but provide only around 3% of global calories, while beans deliver protein with just a fraction of the land, water, and emissions. Per gram of protein, beef produces 10 to 20 times more greenhouse gases than beans, largely due to methane, feed production, and deforestation. That means even small shifts away from red meat can have a bigger climate impact than actions like recycling or taking shorter showers. Beef-heavy diets are an inefficient use of resources, while plant-based proteins like beans, lentils, and peas provide the same nutrition at far lower environmental cost. Scaled globally, these shifts could free land for reforestation, cut emissions, and support healthier diets — showing how powerful personal food choices can be when paired with innovation and policy.”

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Western diet needs ‑90 % beef to stay within eco limits
No need to go 100 % veggie overnight—moderation matters
One swap = 10× carbon win!

Dietary Shifts: Beef VS. Beans

Burger & Bean Burrito Swap

Tang et a l. 2024

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Water: beans sip, beef gulps
Deforestation: less feed‑crop land
Health: fiber ↑, saturated fat ↓
Activity teaser: Protein‑Swap Flash‑Calc → track your CO₂ save!

Dietary Shifts: Beef VS. Beans

Burger & Bean Burrito Swap

Friends of the Earth

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No food shaming—access & culture matter
Informed eaters steer markets → farmers follow demand
Many small plate shifts = big system shift

Dietary Shifts: Beef VS. Beans

Choice, Power, and Culture

SLIDE 44 Spoken Dialogue:

“Food is deeply personal — it’s tied to culture, identity, affordability, and access — which means we should never approach dietary shifts through blame or shaming. Not everyone has the same ability to change what they eat, but when choices are available, they carry real power. Informed eaters steer markets, and farmers follow demand: the rise of plant-based milks or organic produce happened because consumers asked for them, and small shifts in millions of diets add up to massive system change. Cutting beef once a week or adding more plant-based meals may feel small on its own, but together, these choices reshape supply chains and signal new directions for food systems. The key is framing dietary change as empowerment — when culture, access, and affordability are respected, diet becomes one of the most powerful levers for building a more sustainable future.”

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Start‑ups & community enterprises reinvent food chain
Sustainability can drive revenue and cut waste

Innovation: “ReDesign” (Entrepreneurial Action)

Profit with Purpose

SLIDE 45 Spoken Dialogue:

“Innovation in food systems isn’t just about new technology — it’s about rethinking business models so profit and purpose go hand in hand. Entrepreneurs and community enterprises are proving that sustainability can be a growth engine, not a cost. Across the world, start-ups are turning by-products into new goods, like citrus peels into animal feed or bioplastics, while others are creating plant-based proteins that use far fewer resources, or packaging that composts instead of polluting. Community kitchens are transforming surplus produce into shelf-stable soups, and breweries are reusing spent grains in bread or animal feed. Each of these examples shows how aligning profit with purpose can cut waste, regenerate resources, and strengthen communities — while reshaping markets to set new standards for the future.”

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Single‑serve yogurt redo → bio-plastic cup + recyclable foil
Goal: nothing to landfill
Design sprint coming—bring ideas!

Rethink Packaging

Innovation: “ReDesign” (Entrepreneurial Action)

SLIDE 46 Spoken Dialogue:

“Packaging is one of the most visible examples of food system waste, and innovation gives us a chance to rethink it completely. Most single-use plastics from things like yogurt cups end up in landfills or oceans, where they take centuries to break down. But what if packaging never became waste in the first place? Take yogurt cups: the old way combines plastic, foil, and coatings that aren’t recyclable, meaning almost all of them are trashed. The redesign uses compostable bioplastic for the cup and fully recyclable foil for the lid, with nothing going to landfill. That one shift eliminates millions of waste items and shows how powerful design can be. Next, you’ll try this out yourselves in a design sprint: your challenge is to redesign a common food package so it keeps resources cycling instead of ending up as trash. Think creatively — edible packaging, refill systems, anything that reimagines waste as preventable.”

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Innovation: “ReDesign” (Entrepreneurial Action)

Urban Farming Tech

Vertical farms, hydroponics, aquaponics
Closer to eaters = less transport + year‑round greens
Pair with renewables & city compost loops

SLIDE 47 Spoken Dialogue:

“Urban farming technology is all about shrinking the gap between farm and fork by bringing food production into cities themselves. Instead of relying on long supply chains that create waste and emissions, vertical farms stack crops in buildings, hydroponics grows plants in nutrient-rich water with less land and water, and aquaponics links fish and plants in a mutually beneficial cycle. These systems deliver fresher food with fewer transport emissions, produce year-round in controlled environments, and can even close the loop by running on renewable energy and recycling city compost into fertilizer. For example, a vertical farm in New York now grows leafy greens year-round with hydroponics and LED lighting powered by renewables, while compost from restaurants feeds the system. It’s a glimpse of how innovation can transform cities into sustainable food hubs.”

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“Too Good To Go,” “Olio” = surplus meals rescued
Grease → biofuel, pits → textile dyes
Software can be as circular as hardware!

Innovation: “ReDesign” (Entrepreneurial Action)

Food-Waste Apps

SLIDE 48 Spoken Dialogue:

“Innovation isn’t just happening on farms or in factories — it’s also digital, with apps that connect surplus food and waste streams to people and new uses in real time. Platforms like Too Good To Go link restaurants, bakeries, and grocery stores with consumers who can buy unsold meals at a discount, saving perfectly good food from the trash. Olio lets neighbors share surplus groceries or cooked meals instead of letting them spoil. And beyond food, waste by-products are being repurposed — used cooking oil is turned into biodiesel, and fruit pits and skins become natural textile dyes. These examples show that technology can be as circular as compost or recycling bins, creating invisible networks that keep food in use, cut waste, and build community. It proves that creativity plus connectivity can be just as powerful as any new farming tool.”

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Plant meats, lab‑grown, insect protein
Lower land/water inputs than beef
Same taste goal, lighter footprint

Innovation: “ReDesign” (Entrepreneurial Action)

Alternative Proteins

Beyond Burger vs Beef Burger - EcoHungry.com

SLIDE 49 Spoken Dialogue:

“Alternative proteins show how innovation can reinvent food without asking people to sacrifice taste. Since beef has one of the largest footprints in the food system, replacing even part of that demand with new proteins can make a huge difference. Plant-based meats like the Beyond Burger use peas or soy to replicate beef’s taste and texture but with almost 10 times less carbon emissions, far less water, and a fraction of the land. Lab-grown meat, grown directly from animal cells, eliminates the need for massive herds, and insect protein offers a highly efficient option that requires little land or water. Side-by-side comparisons are striking: one beef burger produces 3.7 kg of CO₂ and uses 438 liters of water, while a Beyond Burger produces just 0.38 kg of CO₂ and uses 3 liters of water. The calories and protein are almost identical, but the environmental costs couldn’t be more different. These innovations prove that sustainability and consumer satisfaction can go hand in hand — and if even a portion of global meat demand shifts to alternatives, we can free land, save water, and cut emissions dramatically.”

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Mushrooms on spent grain
Coffee‑ground to fungi loops
SF startups turn curbside scraps → fertilizer pellets & biogas

Innovation: “ReDesign” (Entrepreneurial Action)

Circular Business Examples

The circular food system and upcycled food — Upcycled Food Association

SLIDE 50 Spoken Dialogue:

“Innovation isn’t just an idea — businesses around the world are already proving that waste can be the foundation for profit and sustainability. Breweries and distilleries turn their spent grain into a growing medium for gourmet mushrooms, which can then still be composted or fed to livestock. Cafes are sending used coffee grounds to entrepreneurs who grow mushrooms or make soil enhancers, creating a loop from waste to food to soil and back again. And in San Francisco, companies collect curbside food scraps from homes and restaurants, converting them into fertilizer pellets and renewable biogas. Each of these examples shows that redesigning waste streams isn’t just possible — it’s profitable, cutting disposal costs, reducing emissions, and creating new revenue streams. These circular businesses prove that with creativity, every by-product can become a resource — and they highlight why supportive policies are needed to help scale these solutions.”

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 Why It Works

Waste → value = new revenue
Local jobs & community benefits
Study: Circular economy food models need producers + consumers + policy aligned

Innovation: “ReDesign” (Entrepreneurial Action)

Circular Economy Models in Agro-Food Systems: A Review

SLIDE 51 Spoken Dialogue:

“Circular redesign works because it flips the logic of waste — instead of being a cost, waste becomes a resource that creates new value. By-products like spent grain, coffee grounds, or food scraps can generate revenue as mushrooms, soil enhancers, fertilizer, or biogas, cutting disposal costs while creating new products and businesses. These models are usually local, which means more jobs, stronger community food systems, and less dependency on long supply chains. But success also depends on alignment: producers need to share waste streams, consumers need to embrace new products, and policy-makers need to provide the right infrastructure and incentives. When all three work together, circular food models thrive, showing how innovation can deliver economic, social, and environmental benefits at once.”

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Smart Incentives

Pay farmers for carbon‑rich soils & biodiversity
Subsidize cover crops, agroforestry

Cities-and-Circular-Economy-for-Food.pdf

Ellen Mcarther et a l. 2019

Policy: Collective Action (Systems Change)

SLIDE 52 Spoken Dialogue:

“Policy is the lever that makes diet shifts and innovation scalable by creating the right incentives for change. Instead of paying farmers only for yields, smart policies can reward ecosystem services — like building carbon-rich soils, capturing carbon, or restoring pollinator habitats — flipping the incentive from ‘produce more at all costs’ to ‘farm in ways that regenerate land and climate.’ Subsidies can also be redirected from resource-intensive monocrops toward practices like cover crops, which protect and recycle soil nutrients, or agroforestry, which stabilizes soils and boosts biodiversity. Collective action is key: city governments can drive composting and food recovery programs, schools can model sustainable procurement and educate future leaders, and financial institutions can invest in circular businesses and regenerative farms. When all of these actors work together, policy becomes the glue that scales solutions into systems change.”

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Food‑Waste Targets

SDG 12.3: Halve waste by 2030

France: supermarkets must donate edible food
School: unsold lunches → local shelter/compost

Ellen Mcarther et al. 2019

Policy: Collective Action (Systems Change)

SLIDE 53 Spoken Dialogue:

“Food-waste targets show how policy can make waste reduction a shared responsibility and drive real results. Globally, SDG 12.3 calls for halving food waste by 2030, pushing countries, cities, and businesses to measure and reduce losses. France provides a strong example with its law requiring supermarkets to donate unsold but edible food to charities, turning waste into meals instead of trash. Schools can do the same by redirecting leftover lunches to shelters or compost systems, keeping food out of landfills and building community connections. These policies matter because they reduce methane emissions, cut disposal costs, fight hunger, and return nutrients to soils through composting — proving that rules and targets can turn a massive inefficiency into an opportunity for climate, people, and profit.”

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Food‑Smart Cities

Zoning for community gardens/rooftop farms
Mandatory compost pick‑up
Grants for urban ag & zero‑waste goals

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 54 Spoken Dialogue:

“Cities are where most people live and where most food is consumed, which makes them powerful drivers of change. By adopting food-smart policies, local governments can cut waste, shorten supply chains, and build resilience. Zoning codes can require or incentivize community gardens, rooftop farms, and vertical gardens that put food closer to eaters. Mandatory compost pick-up can make diverting food scraps as routine as trash and recycling, turning waste into compost or biogas. Grants and zero-waste targets can spark innovation, funding urban farming projects, packaging redesigns, and food recovery programs. Because cities concentrate both demand and waste, small interventions can ripple quickly across neighborhoods and scale citywide — making urban policies one of the fastest ways to build healthier, more resilient food systems.

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Regulate the Bad Stuff

Phase‑out toxic pesticides, excess N‑fertilizer
Anti‑deforestation laws + sustainable intensification
Carbon & nitrogen pricing shift economics

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 55 Spoken Dialogue:

“Incentives and grants help reward good practices, but strong regulations are just as important because they phase out the harmful ones. Smart policies can gradually ban toxic pesticides that damage biodiversity, limit nitrogen fertilizer use that drives water pollution and greenhouse gases, and block imports tied to deforestation from beef, soy, or palm oil. At the same time, tools like carbon or nitrogen pricing can shift the economics of farming so harmful practices become more expensive and regenerative ones more competitive. Without regulation, destructive practices remain the cheapest option in the short term — but with strong guardrails, policy makes sustainability the smarter economic choice while protecting forests, soils, and water and keeping food systems within planetary boundaries.”

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a

Lead by Example

Public procurement: 50 % local/regenerative food in schools
Meatless Mondays teach by eating
Our very course = policy in action!

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 56 Spoken Dialogue:

“Policy isn’t only about laws and incentives — it’s also about leading by example, and public institutions are some of the most powerful tools for change. When schools, hospitals, or city governments adopt sustainable food practices, they create reliable demand for regenerative farmers and show communities what change looks like in practice. Procurement rules that require local or sustainable sourcing shift entire supply chains, and initiatives like Meatless Mondays make sustainability part of daily life, not just a classroom idea. Even this course is a form of policy in action, because education itself equips the next generation to rethink food systems and carry those ideas forward. The key point is that when institutions model change on the plate, they normalize it for society — proving that sustainable food isn’t abstract, it’s practical and achievable.”

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Multi‑Level Alignment

International → national → local → campus
Good policy makes sustainable choices easy & profitable
Your voice counts: advocate for better food policies!

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 57 Spoken Dialogue:

“Food policy works best when all levels of governance align, from global treaties down to campus cafeterias. International agreements like the UN Sustainable Development Goals set benchmarks for waste reduction and sustainable farming, while national governments create laws, subsidies, and dietary guidelines that shape food systems. Local governments put policies into practice with compost programs, zoning for gardens, and school procurement rules, and even institutions like campuses or hospitals can lead by example with Meatless Mondays or sourcing from local farms. The key idea is that good policy makes the sustainable choice the easiest and most profitable one. And your voice matters — advocacy can start small, like pushing for food-waste reduction in your school, and ripple outward to influence local, national, and even international change.”

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Collaborate for System Change

Scientists, farmers, business, gov, citizens
EMF: “Unprecedented collaboration required”
No single hero—puzzle pieces fit together

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 58 Spoken Dialogue:

“Food systems are incredibly complex, which means no single hero can fix them — transformation only happens when everyone plays their part. Farmers adopt regenerative practices and connect to local markets; food brands redesign products with plant-based proteins and circular packaging; retailers and restaurants cut waste and normalize sustainable choices; scientists create new tools; governments provide incentives and guardrails; and citizens drive demand through what they buy and advocate for. The Ellen MacArthur Foundation calls this an era of ‘unprecedented collaboration,’ because only when these pieces interlock does the system shift. The big idea here is that system change isn’t about one player — it’s about farmers, businesses, policymakers, and citizens working together to create a circular, resilient food system for the future.”

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Collaborate for System Change

Scientists, farmers, business, gov, citizens
EMF: “Unprecedented collaboration required”
No single hero—puzzle pieces fit together

Policy: Collective Action (Systems Change)

Ellen Mcarther et al. 2019

SLIDE 59 Spoken Dialogue:

“Food systems are too complex for any one actor to fix — real transformation comes from unprecedented collaboration. Waste management companies can compost and recycle nutrients, but they need city governments to provide infrastructure and procurement rules that support circular practices. Cities depend on financial institutions to de-risk investments so regenerative farms and businesses can grow. Learning institutions advance research, pilot solutions, and educate the next generation, while scientists, farmers, businesses, and citizens innovate, produce, consume, and advocate for change. The big idea is that each holds a piece of the puzzle, and only when those pieces connect do we build resilient, circular food systems. There’s no single hero — but together, the network creates the future of food.”

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4P - Planet | People | Profit | Policy
Pick your quadrant(s) & jot down one action idea

Where Will You Act?

The Lens of Reflection

SLIDE 60 Spoken Dialogue:

“As we wrap up, this reflection is your chance to connect everything we’ve covered — from diet shifts to innovation to policy — to your own sphere of action. Sustainable food systems balance four lenses: Planet, People, Profit, and Policy. Planet is about protecting ecosystems through actions like composting or eating less meat; People focuses on equity and health, like volunteering with food recovery or advocating for access; Profit means supporting fair, viable businesses such as local farmers or upcycling enterprises; and Policy creates systemic change, like campaigning for composting in schools or healthier lunches. Take a few minutes to pick one or more of these lenses and jot down one action you could take — personally, as part of a student group, or in your community. Then we’ll share out and gather ideas under each heading, showing how individual actions connect into bigger systems change.”

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Everyone Has a Role

Daily choices add up → markets shift
Today’s learners = tomorrow’s innovators & lawmakers
Your hat can change over time—stay curious!

The Lens of Reflection

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Review Questions

What hotspot did you choose and what kind of waste is there?
What’s one benefit and one challenge of your prototype system?
How could using multiple methods help close the loop on campus?

SLIDE 62 Spoken Dialogue:

“Let’s close with a quick review that connects back to your own prototype ideas. First, what hotspot did you choose, and what kind of waste is there — cafeteria food scraps, plastic packaging, landscaping waste, or something else? The key is spotting the pain points where loops are broken. Second, what’s one benefit and one challenge of your prototype? Benefits might include cutting landfill waste, creating compost for gardens, or saving money, while challenges could be funding, participation, or infrastructure needs. Finally, how could multiple methods work together to close the loop on campus? For example, combining composting with reusable packaging and food donation often creates stronger, more resilient systems than relying on just one fix. Remember, every real-world solution comes with trade-offs, and identifying them is part of systems thinking.”

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Review Answers

Example: The campus dining hall —the main waste stream is post-consumer food scraps, including uneaten meals, fruit peels, and coffee grounds.
Benefit: Turning food scraps into compost and biogas reduces landfill waste and returns nutrients to the campus garden, supporting a circular nutrient loop. Challenge: Requires consistent sorting by students and staff, plus investment in collection bins and composting or biodigester infrastructure.
Composting, food recovery, and farm partnerships could divert most organic waste from landfill—donating surplus food, composting scraps, and converting cooking oil to biofuel.

SLIDE 63 Spoken Dialogue:

“Here are some sample answers you might have come up with. For the first question, one hotspot could be the campus dining hall, where the main waste stream is post-consumer food scraps like uneaten meals, fruit peels, and coffee grounds. For the second, a benefit of a prototype system might be turning those scraps into compost or biogas to reduce landfill waste and support the campus garden, while a challenge could be the need for consistent sorting by students and staff plus investment in bins and composting infrastructure. Finally, using multiple methods is often the strongest approach — combining food donation, composting, and converting cooking oil to biofuel could divert most organic waste from landfills and close nutrient and energy loops on campus.”

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Balance people + planet.

Sustainable food systems meet human needs while staying within planetary boundaries.

Close the loops.

Shift from take-make-waste to circular loops for nutrients, water, and energy.

Use all three levers.

Diets, design & business innovation, and policy work together to scale change.

Act with evidence.

Prioritize scalable nutrient-recovery solutions and pick one concrete first step.

Module 1 Key Takeaways

SLIDE 64 Spoken Dialogue:

“Module 1 shows us that sustainable food systems depend on balance, loops, and levers. First, we have to balance people and planet — feeding communities while protecting ecosystems so systems last. Second, we need to close loops, moving away from the old linear model of ‘take, make, waste’ and instead designing circular systems where nutrients, water, and energy keep cycling, just like in nature. Third, real transformation requires pulling on all three levers — diets, innovation, and policy — because no single solution is enough on its own. And finally, action should always be guided by evidence: whether it’s composting, food recovery, or regenerative agriculture, even one concrete step can start momentum. The challenge is big, but the opportunity is just as big — every choice we make can help redesign food systems to regenerate instead of deplete.”

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What You’ll Learn: Mindmap

SLIDE 65 Spoken Dialogue:

“This mindmap ties everything together, showing how today’s topics connect into one big picture of sustainable and circular food systems. At the core are People, Planet, and Profit, which link directly to lessons on planetary boundaries, circular economy, and systems thinking. Around that core are the three pathways of action — diet, innovation, and policy — each reinforcing the others and tying back to global sustainability goals. As we move through each branch, think about examples we’ve covered, like beef vs. beans for diet, mushroom loops for innovation, or food-waste laws for policy. Notice how the branches overlap — because in real food systems, nothing exists in isolation. It’s all interdependent, and systems thinking helps us see those connections.”

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Career Pathways

Policy & Governance

Sustainable Agriculture Policy Analyst
Food Waste Reduction Program Coordinator
Environmental Regulations Compliance Officer
Urban Food Systems Planner

Innovation & Business

Circular Food Systems Entrepreneur
Sustainable Packaging Designer
Food Waste Upcycling Start-Up Founder
Alternative Protein Product Developer
Sustainability Supply Chain Manager

Science & Technology

Regenerative Agriculture Researcher
Urban Agriculture Systems Engineer
Composting & Soil Health Specialist
Food Systems Data Analyst

SLIDE 66 Spoken Dialogue:

“Food systems careers are diverse and growing, and they span three main areas: policy, innovation, and science. In policy and governance, you might work as a food systems planner or compliance officer, shaping programs that reduce waste or expand urban farming. In innovation and business, you could be an entrepreneur redesigning packaging, developing alternative proteins, or running a start-up that upcycles food waste. And in science and technology, you might research regenerative agriculture, design hydroponic systems, or analyze data to make supply chains more sustainable. Each role looks different day-to-day, but all contribute to building circular food systems. As you think about your own future, ask yourself: which area excites you most — shaping rules and programs, inventing new solutions, or applying science and tech — and why?”

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HOA-A: Global Food Systems Mapping: Planetary Boundaries & SDGs

HOA-B: Bottle Compost & Decomposition Challenge

HOA-C: Low-Impact Diet Challenge

Sneak Peek of Hands-On Activities

SLIDE 67 Spoken Dialogue:

“In Lesson A, we saw why food systems matter and why simply producing more of the same won’t solve hunger or sustainability challenges. Now, Lesson B asks a bigger question: what if we redesigned the system itself so nothing goes to waste? Right now, most food systems are linear — a one-way street where resources flow in, products are made, and waste flows out, leaving behind pollution and degraded ecosystems. But nature doesn’t work this way. In a forest, nothing is wasted — leaves decompose into soil, animal waste becomes fertilizer, and energy cycles through food webs. Our challenge is to imagine food systems that work like ecosystems: where food scraps become compost instead of landfill, nutrients return to soils, packaging is reused or biodegradable, and farming restores land instead of depleting it. The hands-on activities ahead will give us a chance to practice rethinking food systems in this way.”