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The monumental 22 trillion a day challenge

Humanity has faced many challenges from famine, war and pestilence to climate change and COVID-19. So far we have overcome them all through fortitude, imagination and sacrifice. However, the biggest challenge awaits…

What is the 22 trillion a day challenge? 

Fortunately, it’s not more burpees ever attempted in the history of mankind or even the size of the US national debt. What we’re talking about is calories, the energy content of food,  kilocalories to be precise. 

22 trillion is the number of kilocalories that must be supplied each and every day to meet the basic needs of a human population of 7.7 billion and counting. 

The number comes from the estimated average level of energy consumption of 2,800 kcals per person per day multiplied by the number of people on earth. 

An enormous number

This daily challenge applies every single day of every single year and continues to get larger as the population grows and wealth increases. 

22 trillion or 22,000 billion is such an enormous number it’s incomprehensible, a bit like the US national debt. 

What is remarkable, of course, is that 22 trillion kcal is pretty much delivered every single day. 

Through global disruption from financial crises, errant presidents and even a pandemic, the food production and distribution systems keep supplying the calories such that demand is more or less met. 

We say more or less because not everyone has access to the calories that they need. 

United Nations food agencies State of Food Insecurity and Nutrition in the World 2020 report estimates about 8.9% of the world’s population — 690 million people — go to bed on an empty stomach each night and this number is expected to exceed 840 million by 2030.

Meanwhile, data from The Food and Agriculture Organisation of the United Nations (FAOSTAT) shows the average intake in the US is 3,600 calories daily, up a quarter from the level in 1961 with growth in consumption of vegetable oils accounting for more than half of the calorie increase.

This inequity in food for people across the world exists despite most estimates suggesting that global production is sufficient to meet demand. Poverty reduction to prevent hungry and malnourished people remains a global challenge that should be a high priority for everyone. 

We will come back to this in a moment. 

oat cake cookies
Photo by Towfiqu barbhuiya on Unsplash

Natural capital

First, let’s focus on the remarkable fact that 22 trillion calories are delivered every single day through a dizzying array of production systems and supply chains. 

Humanity is extraordinarily good at innovating where there’s a buck involved. If there is profit people will find a way to grab a share of it. The economists call it meeting demand with supply. 

The challenge that sustainably FED recognizes is not so much the magnitude of the calories needed more for a hundred years and more into the future, scary as this is.

Our concern is where all those calories will come from.

Food production involves channelling primary production from photosynthesis in plants into foodstuffs. Fields, feedlots, fisheries and farms of all shapes and sizes generate the calories using applied ecology with and without additional inputs of energy, fertilizer and pesticides.

More simply, calories come from natural capital with occasional subsidies of nutrients and energy.

The reality is that natural capital is finite. 

No matter how we cut and dice it with technologies and pretend that we’ve got access to all sorts of inputs, productive land area is finite as are nutrients in the soil and the ability of ecological processes to restore them. 

The 22 trillion a day challenge is to understand these finite limits and work within them to retain natural capital. 

woman buying fresh fruit at a market stall
Photo by Clem Onojeghuo on Unsplash


That we are currently able to achieve 22 trillion a day, regularly, routinely, day after day, year after year is nothing short of miraculous. 

The concern that sustainably FED helps to address is the uncertainty about how long we can keep this going. We do have degraded soils, we do have a whole host of challenges of intensification that cause environmental disruption, yield gaps that are hard to close, cultural consequences of production systems and above all people getting in the way of sustainable food. 

Poverty leads to malnutrition but so do empty calories. Fixing inequity in food access and food security will be a high priority but so too will maintaining a healthy diet for everyone.

This website is about going deep into this problem to find solutions. 

As a reader and hopefully a participant on the site we hope you can become part of the solution.

Join us with some comments or enrol on an eCourse to further understand how to meet the challenge of everyone’s lifetime

sustainably FED

Hero image modified from a photo by Minna Hamalainen 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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