A food system encompasses the activities, people and resources involved in getting food from field to plate. Along the way, it intersects with aspects of public health, equity and the environment. In this course, we will provide a brief introduction to the U.S. food system and how food production practices and what we choose to eat impacts the world in which we live. We will discuss some key historical and political factors that have helped shape the current food system and consider alternative approaches from farm to fork. The course will be led by a team of faculty and staff from the Johns Hopkins Center for a Livable Future. Guest lecturers will include experts from a variety of disciplines, including public health, policy and agriculture.
Converging Crises (Neff)
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From the course by Johns Hopkins University
An Introduction to the U.S. Food System: Perspectives from Public Health
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Johns Hopkins University
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From the lesson
Food System Sustainability and Resilience
This lesson expands on the concepts of food system sustainability and resilience, and describes strategies that could dramatically improve the food system and the ability of future generations to feed themselves.
Meet the Instructors
Keeve Nachman, PhD, MHSAssistant Professor, Environmental Health Sciences
Bloomberg School of Public Health
Robert S. Lawrence, MDProfessor, Department of Environmental Health Sciences
Bloomberg School of Public Health
Pamela Rhubart BergFood Systems Education Program Manager
Johns Hopkins Center for a Livable Future, Department of Environmental Health and Engineering
The next section of my talk
focuses on a set of converging crises that are all coming together and
presenting major threats to our food system, sustainability, and resilience.
And I start this off with a quote from Christiana Figueres,
who's the head of the United Nations group that's working on climate change.
And she says I feel like I swallowed an alarm clock, that the time is ticking for
a lot of these things.
And it's not like we have endless time to address them,
we've got to address them quickly.
And I'm going to dig into more detail about these crises.
We are in a process of going through a paradigm shift in terms of how we think
about the connections between food security, nutrition, and environment.
So traditionally, we thought of these as separate domains.
Food security, it's real, it's pressing, real people are hungry right now.
Nutrition is this crisis, everybody's gluttons, their obesity is rising.
Environment is this kind of luxury concern, let's save the whales.
And these things were not necessarily seen as connected, or
if there were connections, they weren't really the main important piece of this.
What we really want to do is get the most food to people for the lowest prices.
And there might be a benefit to food security or
nutrition from fixing the environment some place far in the future, but
it wasn't seen as essential or here or now.
And currently, as all these crises that I'm going to talk about have converged,
there's a very different understanding, we see this as now.
And I will say that in the earlier version of this lecture, where it says now,
it said happening right now in distant places, and may eventually affect us.
But when I really stepped back and thought about it, I said no,
I have to edit that and just say now because it's happening right now, and
we're seeing it right now wherever we live.
And there's a concept that technology might help us, it also might backfire,
but whatever it is, we need to do basically whatever we can and
really put in a strong and unified effort to address these linked threats.
So I'm going to start by talking about climate change,
which is an area where I've done a fair amount of work.
And the first thing to understand is that, globally speaking,
as much as 17 to 32% of our greenhouse gas emissions are coming from food.
That's a shocking number, and it's not something that we hear a lot about.
And when you hear global statistics reported, you don't see that number, and
the reason is because often they'll just report
the amount that comes from the food production.
But when you sum up all the other pieces that went into the food,
whether it's the transportation, the land use change,
where if you deforest some land in order to grow animal feed.
You put all those pieces together, you get these estimates in the range of 17 to 32%,
and multiple studies have looked at that kind of thing.
So that's huge, and let's also think about what parts of the food system
are really the ones of greatest concern.
And it turns out that this is not evenly distributed across food items at all,
it turns out that by far cattle production and
other ruminant production trumps everything else.
And so in the United States food system, for example, nearly half
of the greenhouse gas emissions from food are coming out of red meat and dairy.
And there's a desire to think that well, if we eat grass-fed beef,
that's different, in terms of many environmental outcomes, that is true.
But in terms of climate change, the studies have shown that whether it's
grass-fed or industrially-produced beef, as shown in these two images,
essentially the impacts for greenhouse gas emissions basically balance out.
Now, the reasons for the greenhouse gas emissions are quite different.
In either system,
one of the top causes is the methane that comes from cattle belching.
Now, this is actually higher in a grass-fed system than in an industrial
system because the feeds in an industrial system are specially manufactured to be as
digestible as possible, whereas in a grass-fed system,
they're not as digestible.
The second main piece is that you have cattle in an industrial system,
particularly, that are eating manufactured feeds, and
there's tremendous resources that go into making those feeds.
And then you have methane off-gassing from the manure.
And then in a grass-fed system,
that manure is nourishing the soil, so there's the soil then can hold more
carbon within it, so that's called soil carbon sequestration.
So in a grass-fed system, you have a benefit there that sort of balances
against the animal feed production in the industrial system.
And you put all these pieces together, and you take the lifespan of the animals, and
you end up basically equaling out.
So how do we communicate about this?
And one of the challenges is that people don't really want to hear the message
that a food that they really like is so negative for the environment.
And so here, for example, is a study that came out recently that their
finding was reported as lettuce is three times worse than bacon for
emissions, and vegetarian diets could be bad for the environment.
So this story got tremendous play, because everybody wants to hear that.
Well, it turns out that that may be true, however, you would basically
have to eat 22 cups of lettuce to get the calories of two slices of bacon.
This is a very unrealistic comparison that was reported,
and the study didn't even assess whether vegetarian
diets had lower greenhouse-gas emissions than non-vegetarian diets.
It was looking at adherence to dietary guidelines, which include for example,
increasing our dairy because for
nutritional reasons, there has been advice to increase dairy.
The point I want to make here is that, and I'll come back to this idea of how we
reach people with these messages, but I just want to make the point that these
are challenging messages, and people often hear what they want to hear.
What I want you to turn to next is why is this so essential and
why do we need to really focus on meat?
And I want to show you this graphic from a study that was done recently,
and at the top you'll see two bars, they're in blue, if you have color.
One says Agriculture and Land use, and the other says Industry, Buildings, and
Transport, and Energy.
So that's basically the greenhouse gas emissions, where we are right now or
actually a few years ago in 2010, total greenhouse gas emissions.
Now, that dashed vertical line is where we would
need to be to reduce our emissions to in all sectors by 2050, so
that's basically less than half of where we are now.
Let's complicate that and make it even more challenging, the next bar is how much
our meat intake is going to increase with gross domestic product by 2050.
And what you will see is that the extent of greenhouse gas emissions from these
projected meat intake increases come almost entirely
up to the line of the total budget that we would have for
our greenhouse gas emissions by 2050, if we want to keep our climate change
below two degrees Celsius, which is considered to be a very unambitious goal.
So basically, we would have this very tiny space for
all of industry, buildings, transport, energy, all the other industries in
the world would have to fit into this tiny little space if our meat intake continued
to increase in the speed with which it is projected to.
So the next set of bars show what could happen with different interventions.
And what you can see is that if we increase agricultural yields,
we create a little bit of extra space for
these other industries, if we halve our wasted food, we get a little bit of space.
If everybody shifted to what they define as a healthy, low-meat diet,
which is actually some fairly substantial reductions in meat consumption in
wealthier countries, like the United States,
you get even a little farther along towards where we need to be.
But it's only when you put all those three things together that you really
open up any substantial space for all of the other contributors to greenhouse gas
emissions globally and that we even have a chance of hitting these very
modest greenhouse-gas emissions targets.
So now that I have described climate change in one direction in terms of how
our food consumption is contributing to it and
could also play a role in addressing it, I want to flip it around and
talk about the threats to our food production from climate change.
And some of the major threats include, we have extreme weather events
that could threaten crops and livestock, we have increased pest pressure
because of varying temperature changes, reduced invariable crop
yields in many areas due to water availability and carbon and other shifts.
And there's also evidence coming out that the temperature in the carbon could also
change the nutrient content of the crops that are produced.
Oceans acidifying affect seafood production,
which is one of the major sources of food in many places around the world.
And then you have the heat that poses real occupational safety and
health threats to agriculture workers around world.
So these are some of the major effects, and what does that play out as?
We don't know, because there's many models out there, and they say different things.
Some people say that well, we've always managed to reduce our food prices over
time, and that may continue to happen.
And that's possible, but many of the models,
including estimates from the Intergovernmental Panel on Climate Change,
which is the main UN body that looks at this, estimates substantial increases in
food prices on the range from 3 up to 84% by 2050.
And there's also likely a food price volatility where prices go up and
down over time, and what that does is it makes it very risky to be a farmer or
somebody else in the food industry.
And so again, going back to what is sustainability and
how do we keep people producing our food?
That's a challenge, and
it requires in some sense just strong intervention in insurance domains
as well as looking very carefully at how and where we're producing food.
This slide shows simulated changes in yields of 11 crops by the year 2050,
averaged across three different greenhouse-gas emission scenarios, and
using several different models.
What you can see is in some areas, particularly close to the equator,
there would be very substantial percentage change reductions and yields.
And then in some places, at least in the short term, there would be increases and
yields, particularly in the northern latitudes.
It is expected that over time, even in the northern latitudes,
yields will decline with climate change.
So let's turn to briefly some of the international policy related to climate
change.
So I had the opportunity, actually, to go to Paris for the COP21,
which was a major international conference of parties where countries would
come together and set shared goals.
And they did agree on a goal of getting us to only a two degree centigrade rise
in global temperatures, with the idea that 1.5 degrees is really where we need to be.
And they even said that, officially, but they agreed on two degrees.
And how they get there is through these intended nationally determined
contributions where every country puts forward what they're going to do about it.
And almost every country has agriculture in there, so that's good.
In fact, land-use change was second only to energy in the number of mentions.
But here's the challenge, so what are the agriculture and
food actions that they have?
Cropland management, livestock management, grazing land management,
not one of them was talking about food demand.
With all the changes and all the INDCs, we're only getting to 2.7 degrees,
we're not getting even that close to two degrees.
As I had shown, really the only way to get all the way down there is
by starting to talk about food demand.
And it is hoped that in future global climate summits that this topic will be
addressed in much more extensively.
So I've dug deep into climate change,
I'm now going to talk about some of the other converging crises.
And I'm going to spend less time on water and soil and
energy because you're going to hear about them in much more depth in other lectures.
But I'll just give you the brief overview to kind of fill out
the sustainability piece, and so let's start with water.
This is a graphic that was put together to describe data, and
the first picture of California shows the areas of extreme drought, and the darkest
areas are the places that have been labeled as being in exceptional drought.
And it goes all the way down from there, but
most of the state pretty much is in drought.
That's important because California is where we're producing tremendous
parts of our fruits and vegetables, what we depend on for our healthy foods.
And so, for example, California's producing in areas that are very similar
to these areas of exceptional drought.
99% of our almonds, 99% of our walnuts, 95% of our broccoli,
90% of our tomatoes, 74% of our lettuce, and it goes on.
So in terms of that, we need to be thinking about water use in agriculture,
but we also need to be thinking about diversifying and
where do we produce the foods that we need to eat.
Let me talk briefly about soils, and so healthy soils are resilient to drought.
They sequester, or hold onto, more carbon and keep that out of the atmosphere.
They erode less, which means basically, if there's wind or
water running through them, less of them will be washed away, and
the plants can be healthier in healthy soils.
Now, you could put plants in Styrofoam,
and they will grow well enough if you give them fertilizers.
But the challenge is that our current fertilizer production depends on scarce
and costly resources.
And, as I showed in that initial slide, is one of the factors that is
destabilizing us from our planetary boundaries.
We are also losing a lot of soil due to erosion, and
a lot of that is due to current farming practices.
Like tractors running over it that compact it, tilling, which means basically
turning over the soil, too much grazing, not having cover crops,
which is basically when you've harvested your plants, you put down some other crop.
It doesn't have to be something that you're going to harvest for food, but
something that's going to hold and nourish that soil so it doesn't blow away and
so on.
It takes about 20 to 1000 years to create an inch of top soil, and
in the United States, we're losing about an inch of soil every 34 years.
Energy and fossil-fuel use, traditionally,
solar-powered agriculture was producing more energy than it consumed.
And that’s because the sun was adding energy into it as was animals and
people adding their energy into that production.
But today we're very mechanized, and we have a lot of processing and
packaging as well going into our food.
And so it takes seven to ten calories to produce and process and
package every food calorie that we have, and it's accounting for
a fifth of the fossil-fuel use in the United States.
That means that as fuel prices go, so
food prices can go also, not directly, but there are a lot of interconnections there.
You put all this together, and
you add in other threats from biodiversity loss to pollinator loss, all these
other threats that I've mentioned and haven't mentioned, and by some estimates,
we could lose 10 to 25% of our global agricultural capacity by the 2080s.
By another estimate, climate change could result in 20%
more child malnutrition in 2050 compared to a world without climate change.
And it's really important to emphasize that all
of the problems that we're talking about are going to hit those who are poor and
those who are disenfranchised hardest.
So we need to be working in every different way on solutions, but
we also need to be thinking of including and making space for
leadership among those who are hardest hit by the problems that are created.
I want to turn now briefly to talk about meat,
I've eluded to it in several places, and I just want to briefly summarize why
we single out meat so much in terms of all the food items.
And here's a slide that summarizes data on what it takes to make
one quarter-pound hamburger.
There's the animal feed going into it, 6.7 pounds of grains and forage,
52.8 gallons of water, 74.5 square feet of grazing land, and
a thousand BTUs of fossil-fuel energy, and one quarter-pound hamburger.
So the resource use is staggering, so
that's one reason why meat is singled out like that.
Livestock are also responsible, as I mentioned,
for a very high percentage of our greenhouse gasses.
By some estimates, if we adopted all of the best technologies,
we could cut that by 30%, but it's still high.
And I'll talk briefly about seafood as well,
so our dietary guidelines are telling us we need to
be doubling our intake of seafood for nutritional purposes.
And yet, it doesn't really take into account how we're going to get there.
So in terms of wild-caught seafood, the FAO, Food and Agriculture Organization,
has stated that 85% of world fisheries are fully exploited, over exploited,
depleted, or recovering.
And by another study, we could completely overfish our oceans by 2048.
We've got acidification from climate change, so wild-caught seafood is some
place where we really need to be looking at how we regenerate those fisheries.
Agriculture is then seen as a solution, and you're going to hear a lot more over
the course of time about ways of doing agriculture that can be environmentally
beneficial, but it also uses a lot of resources.
So ultimately, it's going to be very difficult to get to this idea,
if not impossible, that everybody could double their intake of seafood.
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