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Transitions to Sustainability: Animals to Plants
This article is part of a broader series called Transitions to Sustainability — a framework for understanding how humanity must evolve in response to the climate crisis. The first transition, Coal to Thorium, explored how next-generation nuclear energy could replace coal as a scalable, zero-carbon energy source for industrializing nations. The second, Oil to Hydrogen, mapped out a path away from petroleum through the creation of a clean hydrogen economy to power transport, shipping, and heavy industry. The third, Electrify Everything, examined how electrification — from homes to vehicles to industrial systems — can dramatically reduce emissions when powered by clean energy. Now, we turn to the fourth transition, arguably the most personal and immediate: shifting from animal-based to plant-based food systems.
Of the four major sustainability transitions outlined in this series, three are primarily technological. But this fourth transition — from animals to plants — is profoundly personal. It touches how we eat, what we value, and even how we think about tradition, identity, and pleasure. It’s also the one that could make the most immediate difference, and one where almost everyone on the plant can take action, every day.
The Cost of our Current Food System
Animal agriculture is among the largest contributors to greenhouse gas emissions globally. It is:
The leading driver of deforestation, particularly in the Amazon, where forests are cleared for grazing and to grow soy — most of which feeds livestock.
A major user of water, with agriculture consuming 70% of all freshwater withdrawals globally.
A significant source of methane, a potent greenhouse gas emitted by ruminant animals like cattle and sheep.
A cause of biodiversity collapse, with monocultures and overgrazing replacing complex ecosystems.
Reimagining the Use of Agricultural Land
By some estimates, transitioning to a plant-based global diet could reduce food-related greenhouse gas emissions by up to 70%, while freeing up as much as 76% of the world’s agricultural land. That’s an area larger than North America and China combined — land currently dominated by grazing livestock or growing feed for animals. As we shift toward more plant-forward systems, this vast land area could be repurposed in transformational ways.
Growing up in New Zealand in the 1980s, we used to joke that there were 20 sheep for every person in the country — and it wasn’t far from the truth. My family would spend summers on a working sheep farm, experiencing firsthand the rhythm of rural life: shearing, lambing, fencing, and long days in the sun. It gave me a deep appreciation for the dedication of farmers and the cultural identity tied to grazing.
But even in New Zealand — a country known for its vivid green of its grazing lands — the model is evolving. Today, innovative farmers are experimenting with silvopasture systems, combining timber production with rotational grazing under native or commercial tree canopies. This approach restores degraded soils, captures carbon, and produces food, fiber, and fuel — all from the same land footprint. It's a practical fusion of tradition and regeneration.
Elsewhere in the world:
In the UK, the Knepp Estate has returned former farmland to nature, supporting rewilding efforts that have brought back species long missing from the English countryside.
In the Netherlands, precision agriculture is setting global benchmarks — growing more food with less water, fertilizer, and land, using climate-controlled greenhouses and AI-powered systems.
In Israel, decades of water scarcity led to the invention of drip irrigation, a technique now used globally. Israel recycles over 85% of its wastewater — the highest rate in the world — much of it purified from Tel Aviv’s sewage and reused for agriculture in the arid Negev Desert.
In the California Central Valley, one of the most productive food regions on Earth, massive irrigation networks and aquifers turn a semi-arid landscape into millions of acres of farmland. With shifting climate and water stress, California is now investing in regenerative soil practices, crop switching, and ag-tech to conserve water while maintaining yields.
In Spain and California, forward-thinking landowners are deploying agrivoltaic systems, where solar panels share land with grazing animals or crops — generating both clean energy and food from the same footprint.
The opportunity is not just to stop harmful practices, but to reinvent what land can do as we focus away from using land for grazing animals to intelligent agriculture: store carbon, grow food efficiently, generate energy, and rebuild ecosystems — simultaneously.
And while the global shift from animals to plants may seem daunting, I know from personal experience that farmers are some of the most adaptive and innovative people on the planet. With the right support and vision, they can help lead the way.
Why Plants? (It’s Not About Perfection)
This transition isn’t about moral superiority or food policing — it’s about systems-level impact and the direction of change.
Our current food system relies heavily on animals for calories and protein. But raising animals for food — especially at an industrial scale — is resource-intensive and environmentally costly. Producing 1 kg of beef requires roughly 25 kg of grain and 15,000 liters of water. In contrast, plants can deliver equivalent nutrition using a fraction of the land, water, and emissions.
A global shift toward plant-based diets — even if partial — could:
Reduce food-related greenhouse gas emissions by up to 70%
Free up 76% of global agricultural land for rewilding, carbon farming, or renewable energy
Dramatically cut freshwater use in food production
But to be clear: I’m not advocating that everyone become vegetarian or vegan. In fact, I say this as someone who spent five years as a vegan and fifteen as a vegetarian. While I deeply value what that period taught me, I eventually returned to eating small amounts of meat, with greater mindfulness around sourcing, quality, and frequency, and with a renewed understanding of the value of meat as a protein source.
What we need is not an all-or-nothing mindset, but a broad cultural shift — away from meat-heavy diets and toward the plant-forward end of the spectrum. If billions of people simply ate less meat, less often, the impact would be extraordinary.
Think of it like this:
Moving from meat 3 times a day → once a day? That’s a huge win.
Swapping a few meals a week for plant-based options? Also a win.
Supporting plant-rich cuisines (Indian, Mediterranean, Southeast Asian) already low in meat? Absolutely.
Choosing high-welfare, regenerative, or locally sourced animal products when you do eat meat? That matters too, as eating local dramatically reduces the transportation component of the food we eat.
This is a transition guided not by purity, but by pragmatism, inclusivity, and impact. The more people we can inspire to move in the right direction, the more resilient, ethical, and sustainable our global food system becomes.
But First, We Must Stop
Before we can build a truly sustainable food system, we need to stop doing things that actively undermine it — economically, ecologically, and ethically. Here are some of the most urgent issues we must confront:
Stop the Most Wasteful Agricultural Subsidies
Many of today’s most damaging agricultural practices are not economically rational — they’re the result of outdated or misaligned subsidies that artificially prop up resource-hungry animal production. Governments around the world spend hundreds of billions annually subsidizing the meat and dairy industries — incentivizing overproduction, depressing plant-based alternatives, and externalizing environmental costs.
One striking example: Saudi-owned farms in Arizona are pumping groundwater from aquifers in the Sonoran Desert to grow alfalfa — a water-intensive crop — which is then exported to Saudi Arabia to feed cattle. This is, in effect, a system of exporting virtual water from one water-scarce region to another to sustain an inefficient meat supply chain. In the middle of a growing climate and water crisis, this kind of policy is not just unsustainable — it borders on madness.
Stop Deforestation for Feed and Grazing
A full 80% of deforestation in the Amazon is driven by cattle ranching and the production of soy — but not for human consumption. Over 75% of global soy production goes to animal feed. We are burning tropical forests to produce grain that will be fed to animals that will be fed to people — a wildly inefficient protein loop that depletes ecosystems and accelerates climate change.
Stop Normalizing Meat-Heavy Diets
In many countries, meat is no longer a sign of prosperity — it's a default diet choice. The normalization of three meat-centric meals per day is not just environmentally damaging; it’s a public health liability. Excessive red and processed meat consumption is linked to:
Cardiovascular disease
Colorectal cancer
Type 2 diabetes
High cholesterol and hypertension
According to the Global Burden of Disease Study (funded by the Bill & Melinda Gates Foundation), poor diet — especially high in red meat and low in fruits and vegetables — is now the leading cause of death globally.
By reducing meat intake and increasing whole plant foods, we don’t just cut carbon — we extend lives, reduce healthcare costs, and improve population well-being.
In Short
We cannot fix the future while still subsidizing the past. We cannot call it progress while pumping groundwater in a desert to grow cattle feed for animals oceans away. And we cannot afford a food culture that feeds our appetites at the expense of our hearts — literally and metaphorically. Sustainability starts not with what we add, but what we stop.
The Power of your Plate
This is the sustainability transition where every individual has agency. Three times a day, we each make a choice that either reinforces or rewrites the future of the planet.
Eating more plants is the lowest-cost, highest-impact lifestyle change most of us can make. And it sends a powerful market signal.
As supply chains respond, menus shift, investments flow, and global diets change — not by command, but by culture.
The Road Ahead
Over the next 40 years, humanity must produce more food than in the past 10,000 years combined. We must do it using less land, less water, and fewer emissions. That will only be possible if we shift from animals to plants.
This isn’t a sacrifice — it’s an upgrade. It’s a reimagining of agriculture as a regenerative, resilient, life-supporting system.
It’s time to eat for the future.
Peter Hill is a founding investor in Our World Two, and online sustainability company, and works as a technical program manager for some of the world's largest technology companies.