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.
Modern Agriculture (Kirschenmann)
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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
Ecological Perspectives on Food Production
The 1938 USDA Yearbook of Agriculture stated, “Essentially, all life depends upon the soil ... There can be no life without soil and no soil without life; they have evolved together”. In this module, we will take a very brief look at the importance of methods of food production for sustainability, resilience, food security and health.
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
[MUSIC]
Hello, this is Bob Lawrence.
Welcome back to the course.
The next talk in this module will be given by Fred Kirschenmann,
a North Dakota organic wheat farmer and beef rancher, philosopher and
spokesman for organic, sustainable farming.
Fred is currently a Distinguished Fellow at the Aldo Leopold Center at
Iowa State University.
And serves on the National Commission on Industrial Farm Animal Production,
cooperation with The Center for a Livable Future,
the Department of Environmental Health Sciences at the school.
He's a marvelous spokesperson for sustainable agriculture.
And in 2006,
we invited him to be the annual Dodge lecturer at the Center for Livable Future,
where he spoke on the public health implications of ecosystem change.
His talk is, What Does Agriculture Have To Do with Public Health?
>> Wow, what a pleasure to be a part of this great series.
I'm really looking forward to it.
And, my responsibility, or my contribution to this is going to be to try and connect
some of the parts of the food and health system that often don't get connected.
We tend to think of agriculture separately and food separately and
environment separately and healthcare separately.
[LAUGH] So what I'm going to try to do is show some of the obvious connections that
I think are there.
And hopefully make a small contribution to our efforts to understand how those
connections work and why they're important both to agriculture and to healthcare.
Let's start first of all by pointing out that this is not a new idea.
A long time ago somebody who's very familiar to healthcare institutions said,
let food be thy medicine and let medicine be thy food.
And so there was that recognition way back in the time of Hippocrates.
That these were not separate silos, these were connected, that food and
health were connected.
And much later, in the 1940s, one of my heroes, Aldo Leopold, also recognized this
connection in that he defined health as the capacity of the land to renew itself.
And by land, Leopold didn't just mean the dirt in the soil.
He meant the whole biotic community, so everything from microbes to earthworms,
to vertebrates, to us mammals.
We're all a part of the same system, and
if the whole thing wasn't healthy then we couldn't be healthy.
And if the whole thing was healthy then it was likely that we could be healthy.
So these are not new ideas.
What has happened, however, is that we have tended to specialize and
to therefore separate these various enterprises.
Because we thought that would make them more efficient.
And so in agriculture we have come up with a paradigm of
production which we call the modern paradigm or the industrial paradigm.
And here is a statement that pretty much captures that paradigm from two
authors who I will point out in a minute.
One of them happens to be a friend of mine which I want to indicate in the interest
of full disclosure.
But here's how they describe in one of their papers the modern
agriculture system.
Modern agriculture has become highly industrialized
in order to reliably produce the largest amount of plant and
animal product possible while minimizing labor inputs.
And that's always been the goal.
The goal has been yield.
Producing as much as possible, and to do that with as little labor as possible.
They go on to say, through the incorporation of numerous components
manufactured externally to the farm, including fertilizers, pesticides, and
technology, the modern system manipulates the land to make it amenable
to the industrial processes.
And so here again, these are all important points that we have a lot of inputs that
are enormously energy intensive that drives this system and
that has made it successful over the last 60 years or so.
And then they go on to say, typically, crops are produced as large hectarage
monocultures, consisting of single genotype planted across an entire field.
So this is that highly specialization, not only in terms of biodiversity.
There's really no biodiversity.
But also in terms of genetic diversity.
We really are looking for just a few traits to do those few things.
And the primary one being yield.
So produce as much as possible.
Most farms, using modern agricultural methods, cultivate only a few crops
grown in simple rotation, such as wheat-fallow, or maize-soybean.
So most farmers now are producing one or two commodities at most.
And they specialize in that,
and then using these inputs make it produce as much as possible.
Similarly, most animals are grown in feed lots or
climate controlled buildings in order to closely monitor feed efficiency and
to guarantee uniform meat, egg, and milk products.
So, here again is Increased productivity, uniform product quality.
So that when you go into the grocery store, at least some people tell us,
everybody wants that pork chop all exactly the same size, or
those apples all the same size and all the same color.
And so,
part of what industrial agriculture tries to do is to provide that specialization.
Cycling nutrients is not a major consideration of most industrial
agricultural systems.
Because the addition of externally derived fertilizers is cheaper and
simpler than collecting, storing, and using manure.
And this is David Keller and Charlie Brummer,
who in their paper on Putting Food Production in Context,
in BioScience magazine, this is their description.
And this is a very accurate description of how the modern industrial food
system works.
So it's highly specialized.
Simplify the system, simply as possible.
And then economies of scale.
So those are the three fundamental principles of industrial agriculture, or
any kind of industrial economy, actually.
Those are the basic principles.
So, what's wrong with this?
This has been very successful in terms of increasing yields.
We have tripled, in some instances quadrupled, the yields of corn and
wheat and rice, these basic grain staples, over the years.
And we have increased the efficiency of our meat production with this system.
So, what's wrong with the system?
Well, first of all, let's take a look at what it does on a landscape.
This is now what typical farms look like in the farm belt.
Here's a soybean field, as you can see, as far as the eye can see.
This is what happens with this kind of specialization.
There are people who think this is beautiful.
So from an aesthetic perspective that may be a desirable on the part of some people.
Some people that I know who drive across Iowa, and all they see is soybean fields
like these and cornfields, and they think it’s pretty boring.
Bt it has some other implications, which we’ll come to in a minute.
But this is what the landscape looks like, here’s a typical cornfield, again,
as far as the eye can see.
All corn, one commodity, very specialized kind of system.
Animal systems look very much the same.
We crowd animals together into feed lots, in order again,
to get those efficiencies, and that quality control that we want.
So there's livestock.
Here's poultry, a typical poultry barn.
Again, this kind of specialization,
concentrating animals together to achieve those efficiencies.
Here's hogs the same way.
These are very typical operations now throughout much of the farm belt.
So, the question that we need to ask is, despite the success in
terms of increasing our yield, what have been some of the downsides?
What are some of the negative impacts?
And, of course, there are some.
First of all, there are impacts on the soil.
If you have large fields of a single crop, particularly if it's had a fair amount
of cultivation, then you get a fast rain and this is what happens in the field.
You get this kind of soil erosion, and we have now in a state like Iowa,
lost about half the topsoil in the last 50 years.
Now farmers, to their credit, have tried to take some corrective actions around
this without Changing the system that go to no till agriculture,
maybe doing a little better job with cover crops occasionally.
But still, when you've got this large of acreage at the same time,
you're going to see some soil erosion.
Here's another example of when you have an area in the field where the water collects
and runs downhill, some fairly significant soil erosion.
This is not as uncommon as we would like to think it is.
So this is one of the impacts, what is happening to our soil.
Another impact has been pointed out by
the United States Millennium Ecosystem Assessment Report.
Now, it's a very large report and
probably none of the students taking this course are going to read the whole report.
But fortunately, they did a synthesis report which came out in March 2005 and
it's only about 70 pages and has an executive summary, but
here's the core and this was a report that was put together by almost
1,400 of our leading scientists from 95 countries.
So, this is not a report that you can dismiss easily.
They worked four years developing this report and
here was their core finding which begins to help us understand part of the impact,
part of the negative impacts of this kind of agriculture.
Their core findings said that over the last half century, humans have polluted or
over exploited two-thirds of the Earth's ecological systems on which life depends.
Dramatically increasing the potential for unprecedented and
abrupt ecological collapses.
Approximately 60% of ecosystem services evaluated are being degraded or
used unsustainably.
In other words, we can't continue this kind of an operation.
Most ecosystem changes, they go on to say were the direct or
indirect result of changes made to meet growing demands of ecosystem services and
particularly growing demands for food, water, timber, fiber and fuel.
In other words,
what the report is telling us is that the very methods that we have used to produce
this successful agriculture in terms of Increasing our productivity is the very
system which has undermined the ecological resources that increase that productivity.
So obviously, if you look at the report this way, we can't continue this,
because we keep undermining the very resources that make it possible for
us to maintain productivity and its our effort to grow food and timber and
fiber and fuel and two-thirds of those are agriculture related activities.
We can't continue that and
then the report goes on to say that the solutions aren't going to be simple.
Solution will be complex.
There is no simple fix for
these problems since they arise from the interaction of many recognize challenges,
including climate change, biodiversity loss and land degradation.
And so, what they're saying to us here is that things like climate change are not
isolated phenomenon.
They are part of this way in which we have used the planet to produce our food and
fuel, and our fiber.
And then they go on to say that furthermore, the loss of species and
genetic diversity.
Here now we come back to that specialization in agriculture where we've
lost species diversity and genetic diversity and the result which
that has had is that it decreases the resilience of ecosystem services,
the level of disturbance that an ecosystem can undergo without crossing a threshold
to a different structure or functioning.
And that's the part that we really have to pay attention to, because what this study
is saying is that what's happening now is that at the same time that we're degrading
these ecological resources on which food production depends, we have also reduced
the diversity which makes it possible for nature to rebound from that degradation.
And so, it's going to be much more difficult for nature to respond to restore
its vitality and that could then take us to a point where and
we know this has happened in the past, there have been at least five extinction
periods in the past when nature had to come back from that.
Some instance, over 90% of species existing species were washed.
And so when the planet came back from that, because there was no resilience
there, it came back of something very different from it was before.
It's one of the reasons that we lost the dinosaurs,
because it was one of those extinction period.
The way that nature came back was not conducive for
dinosaurs to continue living on the planet.
So, we often talk about saving the planet.
This is not about saving the planet.
The planet's going to be fine and
the microbes will bring it back to life again if we seriously disrupt it.
The question is whether or not what it comes back as will be conducive for
mammals to continue to exist on a planet.
So this is serious stuff, this isn't.
So when we think about the point I want to make here is that when we
think about the kind of agriculture that we're practicing,
it isn't just about while it would be nice if we were kinder to the environment.
This is really going to affect us very directly in whether or
not we continue on the planet.
And then of course, they go on to say, if that weren't bad enough,
that more challenges were on the way.
At the same time, it's anticipated that during the next 50 years, demand for
food crops will grow by 70 to 85% and demand for water between 30 and 85%.
And the reason for that is of course,
we anticipate a further explosion of human population.
So, the question then becomes how do we maintain an adequate amount of
productivity given these challenges?
And to me, this means we have to fundamentally change the way we do
agriculture.
We can't continue the way we're doing very much further into the future.
Now, there are other problems too that are part of this with this concentration of
animals, we have, of course, a concentration of manure and
one of the ways to do that in many of these systems is to create these manure
lagoons when the manure from these buildings then goes into the lagoons.
And if you have an exceptional amount of rain fall, they often overflow and
then you have this phenomenon where the rivers and
streams that these flow into then cause fish kills.
And so, it has profound effect on the environment.
So these are all connected and then of course, one of the things we need to
recognize, again is something that something that all to live.
Leopold recognized already back in the 1940s is that there is a relationship here
between density and ecology.
And as he pointed out here in this quote which I love, he says,
the trend in animal ecology shows, he says with increasing
clarity that all animal behavior patterns as well as environmental and
social relationships are condition and controlled by density.
I have studied animal populations for 20 years and have yet
to find a species devoid of maximum density controls in all species
one is impressed by one common character.
If one means of reduction fails, another takes over.
So what Leopold has discovered by studying nature is that in all of nature,
if you have a dense population of any species whether it's in and
he doesn't say plants here, but it's also true of plants, whether animal or
plants, then nature wants diversity, because diversity is what it thrives on.
So, it will reduce that density of population by introducing some kind of
disease or pest to reduce it.
And so what's actually happening out there in these highly specialized agricultural
systems which have these dense species of plants and
animals is that nature is constantly, introducing pests and diseases.
And so farmers have to then turn around and bring in controls to try to control
those, which have a direct effect on human health which we'll get to in a minute.
Now this was not just Leopold blowing smoke back in the 1940s, heres
David Tillman now writing in our present time in an article which he published in
Nature Magazine in which he's saying essentially the same thing as Leopold.
He said, the principles of ecology, epidemiology, evolution and
microbiology and
soil science operate in agro-ecosystems as well as in natural systems.
In other words, farms operate the same way as natural systems.
Although the owners of the businesses were probably shocked,
I doubt if epidemiologists were surprised that Hong Kong chicken operations housing
up to a million genetically similar chickens.
Here again, it's that specialization were susceptible to a rapid and
devastating outbreak of disease last year.
He's saying that this should not surprise us and then he went on to say, when
those running massive livestock operations realize that chronic disease and
catastrophic epidemics are the expected result of high densities and
low diversity.
And when society restricts the release of pollutants from such operations,
it may again profitable for individual farmers.
Or neighborhood consortia of farmers to have mixed cropping and
livestock operations tied together in a system that gives an efficient,
sustainable, locally closed nutrient cycle.
So what David Tilman is saying here is that as this current system starts to
break down, because of this disease-related phenomenon where
specialization and density produce more and more diseases, it becomes more and
more difficult for farmers to sustain that kind of agriculture.
And as that plays itself out,
we may again find ourselves going back to somewhat smaller farms,
more diversified farms, operating in accordance with nature's principles.
And I think that's exactly what will happen.
The current industrial systems will only survive so
long as we have the cheap energy to support them.
And as we all know,
costs of energy are going up as we reach peak global oil production.
So how does this relate, then, to health?
Well, here's one of the key ways.
Newsweek magazine had it on the cover of their magazine couple of years ago.
Antibiotics, the end of miracle drugs.
And what farmers need to do in order to keep these large,
dense operations of animals going is to feed them antibiotics.
Not because they're ill, but to prevent them from getting ill, and
also to promote their growth.
And so, as we'll see in a minute, most of the antibiotics that are used today
are used to sustain these animal operations.
And here we are, here is what the Union of Concerned Scientists in their study have
pointed out.
As you can see the vast majority of antibiotic use is for non-therapeutic
animal feed, up to about 80% of antibiotics are used for that purpose.
They are used for animals as a therapy but a very, very small percentage, and for
human use.
So as this antibiotic resistance develops,
it's clearly from these kinds of production systems.
And of course,
then there are many pathways through which the antibiotic resistance gets into
us into humans through our food, through workers who handle feed and manure, etc.
And of course, through the environment.
So, we can't protect ourselves from this because it's part of all of these
pathways that we get exposed to, these resistant bacteria.
And, this is one of the reasons that increasingly our
healthcare institutions are concerned about how our food is produced.
It's not the only reason, but it's one of the reasons.
Because if physicians lose antibiotics as a tool to deal with disease
then we have a huge, huge problem on our hands.
And then of course one of the other related issues is the food borne illnesses
which come from this system.
And as you can see here from this government study
we have an estimated over 75 million cases yearly of food borne illnesses.
325,000 people who require hospital care, and
5,000 deaths yearly just from food borne illnesses.
And it's part of this system that we've created.
So, we have a number of physicians now who are speaking out about this, and starting
to try to help us to think about how we change our food and agriculture system.
And Ronald Glaser from Minneapolis,
Minnesota is one of those who has spoken out.
And this is from an article in Harpers Magazine back in July 2004 when
he says,medical historians describe the last few decades as
the age of the emerging plagues.
Over population, poverty, ecological devastation and global climate change,
chemical pollution, and industrial agriculture.
All of these factors conspire to create the conditions of unprecedented death by
infectious disease.
And he is saying that, it is actually a public health approach which
has the best opportunity to deal with.
Because in our public health approach we tend to look at systems and
what causes illness in the system, rather than simply the therapy, and
we'll touch on that a little bit later.
So, what this says to us then is that we have a systems problem here that we
have to deal with.
We can't solve this simply by making a few modifications in our system.
The system that we put together, in fact, was a response over a period
of almost two centuries to Thomas Malthus' warning that we were headed toward famine
because population was growing faster than our capacity to produce food.
And so we geared up all of our efforts and we invented synthetic fertilizers,
and we put these specialized systems in place.
Reduced the amount of labor required in order to accomplish that.
And we did that, in a way we should pat ourselves on the back.
What we forgot about was to look at the system from an ecological
systems perspective, and what were the unintended consequences of that system?
And the unintended consequences were some of these, and
we'll look more directly at the impact it has on human health.
But it is a system that promotes disease, that promotes soil erosion,
and has an impact therefore on human health and ecological health.
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