How Much More Food Must the World Produce?

It is the goal of many economists to lift the entire world’s population up to a western standard of living. This increase in living standard would by definition include adopting something like a western diet for everyone. One would hope that this should be a fairly straightforward endeavor — all we’d have to do is improve the productivity of our plant strains, farms, and labour, and these changes would result in the production of more food.

Economists don’t stop there, however, and beyond enthusiastically volunteering the planet to provide all living people with a western diet, many economists also feel that it is the duty of the planet to additionally provide all future people with such a diet as well. Most social statisticians estimate that the world’s population will plateau at around 9 billion people, or roughly 2 billion more than today.

This is an admirable goal generally rooted in good intentions (though not entirely altruistic, however, considering the lucrative profit opportunities such noble causes will present to certain strategically positioned agricultural sectors). But before we get too caught up in grandiose visions of future prosperity, let’s not forget that contrary to what most economists believe, it is not our economies that produce this food; the planet actually produces it. Our economies consume food. Therefore, it’s probably a good idea to first ask the important questions before embarking on such journeys of hope and goodwill towards all humankind:

  1. How much additional food would actually be needed to provide this western-equivalent diet to the entire living and future human populations?
  2. Is it reasonable to believe that the planet could produce that much additional food?

I will first attempt to answer Question #1, which turns out to be a pretty simple analysis, and then later move on to Question #2, which is a bit more involved.

So then, how much food would the world need to produce to provide not only current people with a western diet, but also future people too?

Luckily, the Food and Agriculture Organization (FAO) has extensive country-by-country statistics detailing food consumption which are very useful in making these calculations. They are available here.

Firstly, let’s start with a list of the average per-person Caloric intake for each country (my numbers are shown in red while original data is in black).

Because some countries are absent from the data, the sum of the total world population in this table comes up short of 7 billion. But this is not a problem because I am interested in the ratio of differences between countries, not the total global population. These numbers can be scaled up to 7 billion after the calculation.

You will notice that despite the wide range in overall prosperity between various countries around the world, per-person Caloric intake doesn’t actually vary that much. It ranges from about 1900 Calories per day in poor African nations up to near 3800 Calories in the more affluent developed countries. That’s only twice as much food. This doesn’t sound like too much of a variation in food consumption, as well as the resources necessary to support that consumption, especially since it’s well known that westerners eat way too much food for their health anyways.

So it would be tempting to use a population weighted ratio for each country to bring their diet up to 3500 Calories per-person per-day and then see how much more food would need to be produced globally to provide for this.

This doesn’t look too bad. We’d only need a 26% increase in global food production to bring everyone to 3500 Calories per day. This is certainly a tall order given how the planet’s current ecosystems are strained just to feed us today, but it’s not fantastically too far out of reach.

However, what this 26% figure fails to take into account that is hidden within the numbers is the wide variations between countries in terms of the proportion of those Calories that come from animal sources. While total Calories eaten don’t vary a whole lot around the world, what does vary significantly is the sources of those Calories. And we know from an understanding of the trophic pyramid that it requires many pounds of wheat to produce a pound of meat. This factor can vary from around 6 to more than 10.

So now we need some additional data which breaks down the global variations in diet by Calorie source:

From this it can be seen that there is a much wider variation in diets if we look at the proportion of meat in people’s diets, versus simply Caloric intake, ranging from as low as about 4% in the poorest nations to 40% in more affluent ones (Iceland is the highest). That is 10 times greater, versus 2 times greater if we simply consider a Calorie a Calorie!

Therefore, if we want to bring everyone up to a western diet, not only are people going to be eating 3500 Calories a day, but it seems that about 30% of those will be coming from animal sources. And since producing meat first requires that a large amount of plant food be produced in order to feed the animals, and if we want to estimate how much total food the world will have to produce, then we should also include the production of this animal feed.

What trophic efficiency factor should we use? Typically, mechanized meat production in the US requires about 6 Calories of plant material to produce an equivalent Calorie of animal product. This fairly low figure is a result of the significant fossil fuel and irrigation inputs to mechanized agriculture in the “developed” world. In the less developed world, the ratio is probably over 10, but on the flip side, there is less input from fossil fuels in that kind of lower intensity agriculture. I’ll be generous and use a factor of 6. This could probably be analyzed and broken down more thoroughly, and I may do this in the future if I find the data, but for now this number is sufficiently accurate.

Here are those calculations, and I hid several intermediate columns for brevity’s sake. As expected, Bangladesh would require many more Calories to be brought up to a western style diet than would Austria, which requires none.

This table presents quite a different picture than the one above. It shows that in order to bring the existing world’s population up to a western diet, the planet would have to produce 2.3 times as much food, or a 130% increase. That’s substantially greater than the 26% increase based on the simplistic analysis above that ignored the complications of meat production — in fact, it’s 5 times greater!

And beyond this increased food production required to bring everyone today up to a western-equivalent diet, when we add in the extra 2 billion people soon to be joining us, the amount of food needed jumps to 3.1 times today! That’s a 210% increase! But wait … there’s more — if we instead use a trophic efficiency factor of 10, the numbers then jump to 3 and 4 times current food production, for 7 and 9 billion people, respectively.

These results are not concerned with how that food is produced or whether the planet will be able to produce it; they are merely stating that this is the amount of  extra food that will be required of the planet to achieve the goal of bringing everyone up to a western style diet. There isn’t much room for argument here. The only significant assumption in these numbers is the trophic efficiency factor in producing meat from plants, which I selected as 6. This is actually probably too low on a globally averaged basis, especially since the countries that would require the greatest increase in meat production in order to be brought up to a western diet are also the countries which would not likely be using such efficient factory farming techniques as does the western world. I am also assuming that every culture in the world would aspire to a western-equivalent diet if provided the means; many likely would not, however, as overconsumption is a cultural trait that is pushed on western societies.

Now that we’ve answered Question #1, we can begin to frame the answer to Question #2, which asks if the planet is capable of providing that much biological productivity. Considering that rough estimates put the total amount of global productivity sequestered or degraded by humanity at around 25%, then increasing food production by 3.1 times brings us way up to something like 50% (depending on how much of that appropriation is for food)! That is 50% of the entire productivity of the planet — devoted to humanity! Wow!

I don’t know about you, but that sounds a little scary to me. Considering that the planet is currently severely strained in trying to just feed us living mortals with our current lifestyles, then tripling or quadrupling the amount of food produced to additionally accommodate all the future souls eagerly awaiting their arrival into our world seems like a pretty tall order indeed!

What factors need to be taken into account to determine if this will be possible? Firstly, in analyzing our current food production capabilities, we need to separate out the unsustainable inputs that boost food production today but cannot be expected to continue indefinitely into the future. These include things like:

  • depletion of fossil fuel inputs which facilitate transportation and power mechanized farming equipment,
  • depletion of fossil fuel inputs needed to produce synthetic fertilizers,
  • depletion of other fertilizer sources, like potash,
  • soil degradation due to salination resulting from irrigation in arid areas, and from depletion of soil micronutrients that are not replaced with conventional fertilizers,
  • depletion of groundwater used for irrigation,
  • overfishing, or “fishing down the food chain“. Meat farms do not produce food; they merely shift the location of production of that food. The food was actually produced somewhere else. Salmon farms require significant food fish inputs (smaller fish), and these need to be caught somewhere. This places farmed salmon several rungs up the trophic pyramid above plants, and each step up has a reduction in carrying capacity due to successive trophic efficiency factors,
  • further ecological degradation due to increased human industrialization and contamination across the landscape (and seascape),
  • as fossil fuels become scarce, biofuel production will compete with food production for ecological productivity,
  • loss of biodiversity as natural ecosystems are gobbled up, which would tend to lead to an increased incidence of agricultural plagues, and a general decrease in the planet’s overall functioning given that the biosphere will be centrally planned less by “Gaia” (however you’d like to define that), and increasingly centrally planned by bankers and business tycoons. Not good!

These things are all happening right now. We know that they are going to continue and they can be expected to intensify. Beyond these, there also seems to be additional issues hanging over our future that may or may not lead to significant further constraints on global food production:

  • productivity losses from climate change,
  • loss of productive coastal farmland due to rising sea levels, and the loss of inland agricultural areas as people from coastal areas are displaced inwards,
  • decreased productivity of the oceans due to acidification from increased carbon dioxide concentrations, which negatively impacts the planktonic base of the ocean food chain,
  • potential loss of production line efficiency due to social breakdown in the event of economic collapses or wars,
  • Here’s a scary question: What if the global population doesn’t stop at 9 billion?

Countering these factors which would tend to decrease the productivity of the planet are these other factors which may (or may not) increase it:

  • development of alternative energy systems that may have greater overall potential than current fossil fuel based systems,
  • these energy systems may be able to power desalination plants which could be used to irrigate deserts which are currently unproductive,
  • productivity gains from climate change (the net impact of this remains unknown),
  • possible increased plant growth from higher carbon dioxide levels,
  • gains of productive coastal marine habitats due to flooding of previous land areas,
  • further advances in genetic engineering to develop more productive crop strains,
  • increased trophic efficiency of meat production systems in developing nations,
  • increased food production from intensive and sustainable organic farming methods, i.e. “permaculture”.

Clearly, answering these questions is quite a bit more involved than the first part of this analysis. I’ll continue to work on this as I gather and analyze data.

17 responses

  1. Jim

    I think you need to take into account all of the repressive governments and the fact that it is not in their best interest to efficiently feed their populations. I believe they are using hunger as way to keep their people down and from overthrowing the governments.

    The other issue is many non-western cultures don’t want to take on a western diet. Many cultures probably don’t want to eat as much meat so perhaps they can get healthy doses of protein from the appropriate vegetable sources.

    September 30, 2011 at 12:16 am

  2. Hi Jim,

    Good points. You might be right about cultural differences also contributing to meat consumption. I looked through the whole list again and it seems that the countries which have greater than 30% meat in their diets are European and the countries that were spawned from Europe — North America, Australia, and New Zealand. Iceland is 44%! So culture probably has a lot to do with it. If we look to Latin America then the relatively wealthier countries should reflect what the others would do if they had the opportunity to buy more meat, and that is Chile and Argentina with about 25%. But even these countries have lots of poverty so their meat consumption would presumably rise with improving economic situations. In terms of Asia, yes, there aren’t any countries that really that get up above 30% except for Mongolia which obviously has a culture that eats meat. Most are around 20%. China is 21% and I am guessing that if people gained the economic means to eat more meat, this would probably approach 30%. Thailand is a relatively affluent Asian country but it is only at 12%, presumably because they are Buddhist with lots of vegetarians. India is 8% and I also presume that this would increase substantially with an increase in per capita income.

    But the countries with really low meat consumption in the 3% range are mostly in Africa and I think it’s safe to assume that these people are not eating small meat portions out of personal choice! And that amounts to about a billion people.

    So I re-ran the analysis with a 20% figure and a trophic efficiency factor of 6 and this gives 1.8X and 2.6X for 7 and 9 billion people. With 25% and 6 we get 2.0X and 2.9X. With 25% meat and a trophic efficiency factor of 10 we get 2.6X and 3.5X. So it’s still quite a ways up there, basically because there are a lot of poor people in the world in Africa and Asia who I presume would love to eat more meat if they could afford it.

    And as you say, governments may be repressing people with hunger.

    September 30, 2011 at 3:01 am

    • Josh

      Why in the world would they want to repress their citizens with hunger or for that matter think it practical to do so? Hunger, and extreme conditions of poverty are the usual catalysts in social upheaval. If anything they would want to feed their citizens and promote docile behavior through bio-power.

      December 12, 2012 at 2:49 am

      • Hi Josh, I agree, that’s my point. To offset wealth concentration from the middle class, economic growth is required to provide more and more resources to the middle class, to prevent them from entering poverty. This economic growth requires ever greater consumption of natural resources, and this works as long as the global economy hasn’t hit resource limits. But now, with Peak Oil, it has hit those limits and it can’t grow any more. Therefore, the middle class is increasingly becoming impoverished. This is not what the Federal Reserve wants, since as you say, poverty and hunger lead to revolts etc. But that’s just the way it is because the world is running out of resources and no central bank can print resources into existence. This is why things are starting to fall apart now and this will only intensify as Peak Oil progresses.

        December 13, 2012 at 3:39 am

  3. interesting read

    October 3, 2011 at 12:59 am

  4. pete

    fantastic post! I haven’t seen these numbers anywhere else.

    In my opinion, we should all just forget about having the whole world eat as much meat as we do. (maybe that’s what you are arguing for?)

    better to feed the world a vegetarian diet, which is an achievable goal, and reduce our own consumption of meat in the first world, which is also an achievable goal. As energy gets more expensive, the cost difference between a veggie and meat diet rises and most of us will eat less meat out of necessity. This is the opposite situation as currently, where I think at least in the USA, animal feed production (and food production in general) is heavily subsidized.

    Oh and probably if one wants to dig further into the details, the different staple food crops require different amounts of energy to grow in the industrial fossil-fuel-fertilizer way… I vaguely remember the USA’s main one, corn, being among the less efficient?

    November 10, 2011 at 8:20 am

    • Yes I agree we should be eating less meat, but just imagine the reaction of the consumerism propagandists to this suggestion. Look at how much they deny the blatantly obvious problem of Peak Oil; suggesting that people should eat less meat will not likely be well received.

      November 13, 2011 at 3:31 am

  5. pete

    oh yeah, and if possible, median income (if availible) is a better measure for the purposes of this analysis than mean (per capita) income…. i bet it would make a difference as a big majority of the world’s population lives below its mean income, and their food habits count more as far as bulk food resource consumption.

    November 10, 2011 at 8:26 am

  6. Kieran O'Neill

    Also worth thinking about is how much higher those 3,5k calories/day are than required. Health Canada says that even highly active males at the peak of their life need only 3,000-3,300. Averaged across the population, caloric need per day (assuming a labour-intensive economy) would likely sit somewhere around 2,500 or less. (This would need more analysis to be accurate; figures on age breakdown of population; expectations of activity levels, etc).

    Those 3,500 calories/day (on average!) go a long way towards explaining the obesity epidemic in developed nations, since they suggest that probably 3/4 or more of the population is packing on fat.

    So, the inverse (and equally important) question is, how many people can we adequately feed (to the 2,500 calories/day level), given expected future agricultural capability, and under different dietary regimens?

    It’d be interesting to crunch those numbers. I suspect that we are looking at a future with a lot more people eating something like the 3% meat African diet, whether we like it or not…

    November 17, 2011 at 9:16 pm

    • Hi Kieren, good points. I was actually thinking about that myself. I’ll play around with the spreadsheet this weekend and plug the numbers in.


      November 18, 2011 at 7:09 am

  7. ivan

    Have you heard of a man called Malthus? Writing in the period 1798-1826, he predicted the world would soon be unable to feed itself. The world population was about 1 billion then. And many have echoed his calls repeatedly through the ages. So saying “we are close to running out of food” has been going on for 200 years and they have been repeatedly wrong.

    Back in those days about a third of arable land was needed for feeding animals that did the work like ploughing. But the internal combustion engine released that land. Then industrial production of fertilisers, and then genetic improvements in crops have allowed massive increases both in the land available for food production and in the productivity of that land. The lack of adoption of these technologies in much of Africa means that Africa still has large scope to increase food production. The USA can also release land back to food that is currently being wastefully used for production of industrial ethanol.

    Increasing demand for meat in developing countries will increase the price of meat. In Europe meat has never been so cheap. But the Chinese are just starting to import meat. The price will go up, and we will equilibrate to a diet where we eat less meat. We don’t need to eat so much anyway. Plenty of once cheap staple dietary items have become expensive luxuries, like oysters and eels. We don’t say the world is coming to an end because poor Londoners can no longer satiate their hunger on oysters and jellied eel.

    I was in Ethiopia 12 years ago. They kept on having famines even back then. There are now at least 12 million more Ethiopians, as they increase their population by over 1 million per year. Somehow life carries on there.

    December 13, 2011 at 8:56 pm

    • Hi Iviehoff,

      The problem with criticizing Malthus’ predictions is that the laws of thermodynamics hadn’t even been developed when his essay was written. People were just beginning to understand energy. So any numerical predictions based on his work would be mostly meaningless because people had no idea how energy cycles through ecosystems back then. But his observation that populations crash and ultimately are limited by ecology was and still is a valid one.

      Nowadays we have an extremely good understanding of how energy works, and cycles through ecosystems to provide food for us. We have taken advantage of that knowledge to push the limits of ecological productivity to produce more food and to appear to escape the limits described by Malthus. But we haven’t escaped them; we just learned how to push them. And what is interesting is that all of the techniques you describe for increasing agricultural yields are very heavily dependent on fossil fuel inputs (and fresh water). Apparently in the industrial world we use 10 Calories of fossil fuel energy to produce and distribute one Calorie of food energy.

      And when those fossil fuel inputs are removed, ecological productivity will generally decrease to less than what it was before the intensive agriculture was begun, due to ecological degradation.

      That fossil fuels are a finite resource is undisputed; the disagreements concern how close we are to that ending. Considering that the largest known deposit in the world that is being touted as the solution to our energy problems, Alberta oil sand, has an energy return of only 3, and that the whole deposit amounts to 6 years of global oil consumption (actually, when you factor in the natural gas that represents 1/3 of its energy footprint, it’s more like 4 years), that tells you where we are along the trajectory of Peak Oil. This compares to energy returns of 100 or 200 historically from Saudi Arabia’s wells when they were first developed. In the last 10 years global oil production has basically not increased. This looks a lot like Peak Oil to me.

      As the EROEI continues to drop, we will be required to consume exponentially increasing amounts of coal and natural gas to make up the difference, and they too will reach their own diminishing EROEI’s.

      Maybe some miraculous new alternative technology will come to market to save us all but I prefer analysis over faith in these matters and realistically there isn’t anything that could be brought up to speed in time. Maybe technically it might be possible, but socially, it will be a difficult task because the media is brainwashing people into believing that fossil fuels are plentiful and that the eco-freaks are the cause of all the ills, so there isn’t much political will to develop alternative energy.

      Here is a frank discussion of feeding the world to 2050. The authors are “cautiously optimistic”, but they don’t really consider the impacts of Peak Oil, so while it’s a good analysis, I take home the message, “not likely”.

      December 14, 2011 at 5:26 am

  8. ivan

    Thermodynamics clearly presents an upper level to production, albeit that Africa remains very considerably below its thermodynamic limits for production at the moment, and the US is wasting a lot of its land for uneconomic biofuel production. Our efforts at stretching those thermodynamic limits are achieving diminished returns, and the dogmatic anti-GMO attitude of some important parts of the world doesn’t help either.

    But I would give the price system a greater role in rearranging production. Today in Argentina the consumption of meat is falling because cattle production is less profitable than soya, the price of meat goes up, and at higher prices the people buy less of it. So Argentina is increasing the number of people it can feed from its land, simply by responding to price signals.

    If we do have to greatly reduce the role of oil in making fertiliser, then there is a new and large problem to be solved, I acknowledge.

    I followed the link to this blog from the Thorn Tree and you correctly identified my posting name there.

    December 14, 2011 at 11:57 am

  9. kee

    A bit nitpick to your last points:
    As a farmer I am very sceptical to the proposed yield effects of increased CO2 levels, as today’s level in most cultures is far from being the limiting factor. Otherwise why do we get a yield increase from irrigation and NPK fertilizing?
    A roundabout way the claim may have some merit is by way of CO2 being a greenhouse gas leading to warmer, wetter climate and thus more mineralization in a given soil and longer growth periods in high northern latitudes…
    To sustain a fertile soil over medium-long timespans a crop rotation that include grass/clover leys has been proved this far to work. To produce human food from this phaze in the cycle you’ll need ruminants, but at a drastically decreased rate from today where cattle in industrialized countries have large grainfeed propotions in their diet. Now, having ten cows at each farm to utilize the grass grown seems to be a tad bit unrealistic at the moment- but there is such a thing as cooperation, not everyone has to do everything simultaneously.

    February 16, 2012 at 12:38 pm

    • Hi Kee, I actually agree with your points, I was just putting them down for completeness, since they are often encountered in the AGW “debate”. Regarding CO2 increasing crop yields, I need to do some more research (where is the time…) but it seems that this only affects plants using C3 photosynthesis, and only in labs where there are no other limiting factors, and not yet out in the field, so I am as skeptical as you are.

      February 17, 2012 at 3:00 am

  10. Tibor

    And where does the whole perfectly good food which is rotting away fit in? Half of it is wasted FFS!

    November 2, 2012 at 11:48 am

    • Yeah god point. I included this factor in my later post on ecological productivity. This post was just quantifying how much additional food would have to be consumed by both people and animals. To provide that much food there’s a whole host of other factors than need to be included like you said, like food wastage and another big one is stems, roots and leaves that must be produced along with the food. We can’t just take all those off the site as biofuels because that would cause more degradation and require more fertilizers to compensate. If you have a reference to the percent of our food that gets wasted I’d like to see it, since I don’t have a very good source.

      November 3, 2012 at 1:01 am

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