May 21, 2026

We could feed 14.5 billion with today’s cropland. Why aren’t we?

by Paul West, Ph.D., Emily Cassidy and James Gerber, Ph.D.

Graphic showing where cropland calories go

Key Takeaways

Enough calories are produced on the world’s croplands to feed 14.5 billion people. But just 50% of cropland calories are available as food – and even less than 50% when food waste is taken into consideration.
For every 100 calories produced on croplands, 45 are eaten, 40 are fed to livestock, and 15 are used for other nonfood products such as biofuels.
The food, agriculture, and land use sector generates a staggering one-third of all greenhouse gas emissions. While our global food system is becoming less efficient, shifting diets represent a potent and underutilized climate solution.
Creating a more sustainable global food system is most easily achieved by targeting a small set of solutions in specific regions that can generate significant impacts.

Did you know enough calories are produced on the world’s croplands to feed 14.5 billion people?

But it’s not just about how much we grow – it’s what we do with what’s grown.

In a recent study building upon our previous work, we decided to ask a simple question: How many of the calories produced on croplands today are actually available as food?

It turns out the answer is only half.

So what’s the story behind these disappearing cropland calories, and why are so many missing from our plates? After all, understanding the pathways calories travel out of croplands and into the wider world is critical, given the global food, agriculture, and land use sector generates a staggering one-third of all GHG emissions.

Thankfully, as we learn more about how crops are used, we can not only make more informed, thoughtful decisions about what we eat at home, but also take action to make our food production practices far more efficient and environmentally sustainable. In doing so, we can transform a sector posing one of the world’s great climate challenges into one that provides some of our most potent climate solutions.

Where do all of our cropland calories go?

Crops can be divided into three big bushels. Food makes up the biggest bushel and is filled with grains, starches, beans, nuts, oilseeds, fruits, and veggies. The next biggest bushel is crops used for feed; it mainly contains corn (maize) and soy. And a third, much smaller bushel – used mostly to make biofuels – is largely filled with corn, soy, and sugarcane.

Here’s the basic breakdown: For every 100 calories produced on croplands, 45 are eaten, 40 are fed to livestock, and 15 are used for other nonfood products, such as biofuels.

The journey from feed to food

Not all feed ends up as food. It takes more than one calorie of feed to produce a single calorie of meat, dairy, or eggs, and some livestock products are more efficient than others. For example, it takes 2.5 calories of feed to produce one calorie of milk, and 4.5 calories of feed to produce one calorie of eggs. Producing meat from feed is by far the least efficient of all. A calorie of chicken or pork requires eight to 10 calories of feed, while beef – the most calorie-intensive meat of all – is an outlier, with a whopping feed-to-food ratio of 33:1.

Between 2010 and 2020, crop production worldwide rose by 24%. That’s good news. But during the same period, the total calories available as food only increased by 17%. What accounts for this disparity?

The answer is right in front of us: Our global food system is becoming less efficient. While total calorie production increased between 2010–2020, the percentage that was directly consumed decreased, while the percentage used for feed and nonfood uses such as biofuels increased. And there’s another important layer of nuance – beef consumption increased during that decade, meaning that fewer calories of feed were being turned into food.

Unfortunately, calories used for feed but not converted into food are “lost” in the system. Consider that even though 40% of all calories produced are used as livestock feed, only 5% end up as meat, dairy, and eggs.

Put another way, 35% of all calories produced on croplands are eaten by animals but not converted to human food, while another 15% of calories are lost to biofuels production and other nonfood uses. That means only half of the calories produced on croplands are available as food.

The graphic below provides a more detailed breakdown of calories available as food and calories lost in the global food system in 2020.

Understanding croplands’ environmental impacts

Agriculture is the largest land use on the planet – taking up almost 40% of all land. That’s why it’s so important to use these lands wisely to meet the food needs of a growing population while minimizing environmental impact. The type of crops planted, where they are grown, and how they are used all combine to determine croplands’ cumulative environmental impact.

Food waste – accounting for about one-third of all food produced worldwide – exacerbates the inefficiencies of how calories are used. That means even fewer calories than estimated here – in other words, even less than 50% of total cropland calories – ultimately make it to our plates. All of the financial costs and environmental impacts associated with land, water, nutrients, feed crops, and more are embodied in that wasted food as well.

It’s probably no surprise beef has the most outsized impact on climate – 5% of the world's annual greenhouse gas emissions come from methane produced by livestock. That’s equivalent to half of all road transportation or half of all electricity used in buildings worldwide. On top of the emissions from simply being ruminant animals, cattle impact climate through deforestation (clearing natural lands for cattle pastures has been the leading cause of commodity-driven deforestation over the past 20 years), manure management, and intensive nitrogen fertilizer use to grow livestock feed.

Changing diets in a changing climate

Diets are the biggest driver of calories lost in the food system. The food we eat is integral to our culture, which is one of the primary reasons dietary shifts are often considered too controversial and unchangeable. In reality, however, diets have changed drastically in the past. Think of the fad diets in the United States over the past half-century. The high-protein, low-carb Atkins Diet was all the rage in the 1970s – and again in the 1990s. The no-fat fad dominated the 1980s.

But by far the biggest change in our diet in recent decades – both in the United States and across the world – has been a shift toward consuming more and more meat. From 1960–2010, per-person meat consumption worldwide increased by about 60–80%.

While crop-use statistics are not available prior to 1960, what we do know from our research is that we continue to use more crop calories than ever to produce meat and dairy. The amount of crop calories used for animal feed increased 31% between 2010–20 alone, further reducing the efficiency of our croplands.

A healthier option on the menu

There are many compelling reasons to seriously commit to a changed diet. For one thing, modern diets that are particularly high in beef consumption – a common practice in many higher-income countries – are a leading cause of heart disease. Healthier, less meat-intensive diets are also typically healthier for the planet. For example, Mediterranean diets, heart-healthy diets, and vegetarian diets all improve overall health while generating a smaller impact on climate and habitat loss.

And – crucially – eating habits don’t need to change a lot to have a big impact.

In our research, we assessed how many people could have their calorie needs met if beef consumption in food-secure, higher-income countries followed the Planetary Health Diet, in which beef consumption doesn't exceed about one hamburger or one small steak each week. Even if meat consumption stayed the same as a result of pursuing this approach and the excess beef above the recommended level were replaced with chicken, adhering to the Planetary Health Diet would provide enough calories for 850 million people. And if meat consumption were substituted with lentil consumption, enough calories to meet the calorie needs of 1.2 billion people could be made available.

While these fairly simplified scenarios don’t address all nutritional needs, they still emphasize a critical point: Shifting diets and reducing food waste are potent and underutilized climate solutions, given that they serve as a big lever for improving the efficiency of the global food system and reducing its overall environmental impacts.

Focusing our interventions on key leverage points

Like many big climate challenges we grapple with today, inducing meaningful, durable change in our mammoth global food system is most easily achieved by focusing on the system’s leverage points. That’s because targeting a small set of solutions in specific areas can create significant impacts.

Countries such as India, China, and several others across Africa mostly grow crops that people eat. But that’s not the case in other countries – and that’s where the untapped opportunity lies.

In fact, a few countries and crops offer the greatest opportunities to increase food production while reducing agriculture’s impacts on biodiversity, climate, water availability, and water quality. The same goes for lowering the environmental impact of diets and biofuels. For example, changing diets in the United States and Brazil – along with modifying biofuel production practices in the United States, Brazil, Indonesia, and the European Union – could make a real difference. While all actions, everywhere, have some degree of impact, modest changes to diets and biofuel production in these countries in particular could deliver big results at the global level.

Putting our blueprints into action

So where do we go from here? Shifting to healthier diets is one of the most impactful actions individuals can take for improving both their health and preserving the environment. By focusing on eating the recommended amount of beef – or even less! – we can deliver big results for both ourselves and the world around us.

And not only is positive, lasting change possible – it’s already happening. Although meat consumption commonly increases with income, several high-income countries are shifting their diets to a higher percentage of calories coming from grains and fewer from meat.

There are, of course, limits on the transformative potential for redirecting calories once they leave croplands; It would be foolish to think people would eat all the calories used for feed or fuel, for example. That wouldn’t provide the micronutrients our bodies need, and it wouldn’t taste great, either. Similarly, while cropland currently used to grow feed for livestock would realistically not all be restored to natural ecosystems, there is nevertheless clearly a major opportunity to shift the use of an area of cropland the size of the European Union.

Working the leverage points at our disposal, we have a big opportunity before us to not only reduce rampant food waste, but also usher in a new era of sustainability on the world’s croplands and in our overburdened global food system more broadly.

And thankfully, while so many climate challenges can feel overwhelming and insurmountable, this particular challenge is one we can resolve day in and day out, starting tonight: It starts with us and what’s on our dinner plate.

Paul West, Ph.D., is an ecologist developing science-based solutions for sustaining a healthy planet for people and nature. At Project Drawdown, Paul assesses how climate solutions can create win-wins and trade-offs for conserving biodiversity, creating a sustainable food system, and otherwise improving planetary health and human well-being.

Emily Cassidy is an environmental scientist and writer, with expertise in agriculture, ecology, and land use. As a research associate at Project Drawdown, Emily evaluates the emissions mitigation potential of climate solutions in the food system.

James Gerber, Ph.D., is a data scientist with expertise in agriculture and land use, modeling of crop yield futures, and ocean wave energy. He uses various analytic techniques to assess the effectiveness of climate mitigation solutions in the land use sector and their impacts on human well-being.

This work was published under a Creative Commons CC BY-NC-ND 4.0 license. You are welcome to republish it following the license terms.