Explore how food intersects with public health and the environment as it moves from field to plate.
Wasted Food: Putting 40% of Our Food Supply in the Landfill (Neff)
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Do curso por Johns Hopkins University
Introdução ao Hábitos Alimentares Americano: Uma Perspectiva de Saúde Pública
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Johns Hopkins University
56 classificações
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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.
Conheça os instrutores
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
In the next section, I'm going to talk about waste of food.
So, essentially, we put 40% of our food supply
in the United States in the landfill, 30% globally.
It comes to a cost of about $161.6 billion,
or 1,249 calories per person per day.
However you calculate it, it's pretty staggering.
When we waste this food, essentially, what we're also doing is taking 35% of
the fresh water we consume, 31% of our cropland and 30% of our fertilizer, and
basically taking it straight to the landfill.
It's staggering, and 95% of food that's wasted goes straight to the landfill.
There are other places where it goes, like down the drain, and so on.
And food that is wasted is the largest component of municipal solid waste.
And, there, it releases almost a quarter of our methane emissions.
And methane is a powerful greenhouse gas.
What's also interesting is that we've
had a 50% increase in waste in the United States since the 1970s.
So if we can increase the waste,
then in theory we can also get back to a lower level.
Let's talk about this globally.
So, globally speaking,
in terms of water use if you took all of the food that's wasted around the world,
it would be the number one user of blue water for agriculture.
And, similarly, if you took all the food that's wasted,
it would be the number three emitter of greenhouse gas emissions.
Just think about that.
So there's a lot of places that you can go to address this.
And in the United States and many other higher income countries, the majority of
food that's wasted, by some estimates about 40%, comes directly from consumers.
And as much as another 40% comes from what's known as consumer facing
businesses, which could be retail, and restaurants and so on.
We want to be careful not to blame the consumer,
but we can't address this without really looking at what's going on with consumers.
So here's some results from a research we did about asking consumers some of
the reasons that they discard food.
I just want to highlight two pieces of this that really stood out to me,
which was that the number one and number two reasons were concern about food
poisoning and wanting to eat only the freshest foods.
And why that's interesting is because those are both messages that we in public
health have given out to people.
And I would never tell people to eat food that's actually a risk.
But I think that there may be a need to help clarify what food is actually
a potential risk for food poisoning, such as through addressing date labels.
And we tell people the foods should be fresh, it should be beautiful.
That's how we motivate people to eat their fruits and vegetables.
But we may want to look at other messages that can also be motivational.
The next one on that list is I compost uneaten food, so it doesn't bother me.
And that's also a real big education message that has to be addressed
because that question was just among those who actually compost.
And in many areas of the country,
composting is done at the municipal level now.
We need people to understand, as these composting programs proliferate,
that you want to prevent that food from getting to that stage in the first place.
You don't just want to throw it out.
It's not value neutral to throw it out.
We also asked people what motivates wasting less?
And, interestingly, right at the top of the list there is saving money.
And then comes a number of things related to kind of responsibility,
setting an example for children, managing your household efficiently.
What's really interesting is that the very last motivation there is greenhouse gases,
energy, and water.
So even though we know that the environmental impacts are huge,
we have to think about what strategies we use in terms of reaching out to people
about these issues.
Now, I want to say this is a survey, it's self-reported.
We know that there's a lot more that goes into consumer waste than there are reasons
that people are going to self-report.
And some of it is things that are happening much farther up the food
chain on our behalf like package sizes and things like that.
But that's just data from the national survey.
And when I tell people I did a survey,
one of the first things they want to know is so what did people say?
How much do they waste?
And I want to make the point,
and this could be said to be true about much research on food.
If you want to know how much food people are wasting,
the best thing to do is go through their trash.
And the second best thing would be to ask them to keep a diary.
And the very last, best way to find out how much people waste is
through giving them a survey or questionnaire.
People are really not aware of it, and they aspire to do better.
And so here's what happens when we ask people how much food do
you throw out verses the average American?
And we have a classic example of the Lake Wobegon effect,
where 73% of Americans say they throw out less than the average American.
So what do we do about wasted food?
This is a graphic of the Food Recovery Hierarchy.
And it's got more rows in it, but it's essentially a version of the old recycling
concept of reduce, reuse, recycle.
So our very first priority should be source reduction.
We want to stop that food from having been created or from purchasing it.
We want to prevent that food from coming into the world and into our homes.
Second thing is we want to get food that's still perfectly good
to people who need it.
And I'll say, you may notice I always say wasted food and I don't say food waste.
And the reason is because waste is a verb and food is a noun.
And we want to say that, for feeding hungry people,
we are feeding them food that would otherwise be wasted.
But we don't want to feed them waste because nobody wants to eat waste.
The level of benefit of each of these levels goes all the way down until
the last, least preferred, item is putting it into the landfill.
The reason compositing is so low is because, while it is true that you're
getting other benefits out of the compost by nourishing the soil, there are so many
resources that have gone into not just producing the food that gets composted,
but then also processing it, distributing it, eating it, cooling it, cooking it.
All those other resources are also wasted when you take that food and
you compost it.
The United States and the United Nations and others have pledged to halve
the amount of food that we waste by 2030, which is an ambitious goal.
It's an exciting goal that there's an opportunity to really push on it.
So what does it take to get there?
A group called ReFED put together an analysis looking at 27 solutions.
They didn't go all the way to a 50% reduction, but
they said what would it take to get a 20% reduction in 10 years?
What they found is that the greatest economic value per ton
comes through standardized date labeling, that's sell by, and use by and
things like that, consumer education campaigns and adjusting food packaging.
And the greatest amount of food, but often at a very high cost,
that could be kept out of landfill is through centralized composting,
centralized anaerobic digestion, which is basically taking that food and
generating methane out of it, or energy, and then water resource recovery.
Basically, getting the water out of it with the methane digestion.
That's where you get your most food from.
Here's a graphic showing these solutions.
And I don't expect you to be able to read this, but
what you can see from it is that the bars that are the tallest are the ones where
you get the biggest economic value per ton.
And the ones that are the widest, which are basically almost flat across
the bottom, are the ones where you keep the most food out of the landfill.
And the darkest blue ones are focused on prevention.
These are some of the ones that have the greatest economic value per ton.
So these are changes that don't take a lot of money to implement, and
they could really make a difference in terms of preventing waste.
So those are at the top of the list.
The green is recovery.
They're not incredibly cost effective, and they don't divert tremendous amounts of
food either, based on the productions of what can be done.
But that doesn't mean they're less valuable.
The human impact of that can be tremendous in the public benefit.
So just because they don't come out at the top on either criterion doesn't mean
they're not really important.
And then, finally, the recycling ones like municipal composting and things like that.
They're incredibly expensive, but they are the ones that have the greatest
potential to keep the most food out of the landfill, and
that's why their bars are so very wide.
Some doll it up,
and they said that if we put in $18 billion to do those 27 solutions,
we could have $100 billion in net societal economic value as a result of this.
And that comes through, both benefits in terms of feeding people,
environmental water benefits, and so on.
A lot of different types of benefits.
So wasted food is an area where there's been a tremendous amount of
increased energy and interest lately.
And that's so exciting because there's so much potential to do so
much more to really address it.
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