Dr. Nicholas Christakis, researcher and Harvard professor of medical sociology

(Music)

Mark Masselli: This is Conversations on Health Care. I am Mark Masselli.

Margaret Flinter: And I am Margaret Flinter.

Mark Masselli: It's the dog days of August and Margaret and I are on vacation
but we planned ahead and we are bringing you a brand new episode for your
listening ears.

Margaret Flinter: Alright, Mark so let’s jump right into today’s show and introduce
our guest. Today, we are speaking with Dr. Nicholas Christakis, who has gained
national attention for his research on social networks. We will speak with Dr.
Christakis about how social structures and socioeconomic variables profoundly
influence health. We are delighted to welcome Dr. Christakis to our show today.

Mark Masselli: You can hear all of our shows on our website www.chcradio.com .
You can subscribe to iTunes to get our show regularly downloaded or if you like
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(Music)

Mark Masselli: Today, Margaret and I are speaking with Dr. Nicholas Christakis.
Dr. Christakis is known for his research on the social factors that affect health,
health care and longevity. He is a Professor of Medicine of Medical Sociology
and of Sociology at Harvard University. Welcome, Dr. Christakis.

Dr. Nicholas Christakis: Thank you for having me.

Mark Masselli: Yes. You know your groundbreaking study in 2007 involving
social networks and obesity made headlines with your findings that obesity is
socially contagious. The study found that someone’s likelihood of becoming
obese went up by 57% if a friend was obese, 40% if a sibling was, and 37% if a
spouse was, in the closest friendships the risk almost tripled. Can you pull the
thread for us if you will of where did you get the idea for this study, how did you
carry it out and what can we learn from it today?

Dr. Nicholas Christakis: I think what was happening around the time when my
colleague James Fowler and I began thinking about this around 2002 was that
there had been a lot of talk about the obesity epidemic and it was clear that
obesity was epidemic in one meaning of the word which is that there is more of it
than there used to be. Even in the last 10 years we have gone from about 20%

of Americans being obese to 30% and fully two-thirds of Americans are now
overweight or obese. And James and I wondered whether we could understand
obesity as an epidemic in the other meaning of the word not just that there is
more of it but was it potentially something spreading from person to person, was
there a literal contagion not just a metaphoric contagion. And so we wanted to
see whether we could find and analyze kind of data that was not yet widely
available at that time, the kind of data that showed people’s social interactions
how they were embedded in these face-to-face networks and the kind of data
that also had information about their weight, and the data that included both
changes in their weight and changes in their social interactions across time, and
it was not easy to find data like this. We bumbled though across some paper
records that had been kept at the Framingham Heart Study, a very famous study
that’s been ongoing since the 1940s and we computerized those paper records
and were able to reconstruct the social ties among the participants of that study.
And as a result, we could see who was whose friend, who was whose neighbor,
who was whose spouse, who was whose coworker, who was whose sibling and
map those interactions as they changed across time as people friended and
befriended each other, the old fashion befriending like the real face-to-face
befriending not the modern sort of befriending. And as they married and divorced
each other and changed where they lived and so forth we had all that information
and so as a result we were able to kind of tease out how does weight gain in one
person how is it associated with weight gain in other people to whom you are
connected. And we used a variety of statistical techniques because there are
also a variety of complications here in developing confidence in this assessment.
We found evidence that there was an association between your weight and the
weight of your friends, your friend’s friends and even your friend’s friends’ friends
people you don’t even know. So that was the first study we published in 2007
and then since then we have looked at a variety of other phenomena as well. I
should say one of the things, actually two other things; first I should say that we
found both weight gain and weight loss can spread and second, I should say that
our work was intended to describe what was happening in the world, it wasn’t
intended to be normative. We were not trying to suggest prejudice against
people of any one or another body size; we were just trying to understand what is
a factor that might have been contributing to this epidemic in our country.

Margaret Flinter: Well Dr. Christakis, I think you are doing an amazing job of
helping people to understand that and you have also written very compelling, far
from creating prejudice, I think you have written very compellingly about just the
impact that other factors gender, race, ethnicity, education, income level, marital
status, all these variables have in health and also in disease. And I was so
struck particularly by your writing and I am not sure I am quoting the exact
numbers right but you talked about the hundreds of thousands of lives maybe
400,000 lives that could be saved each year if people didn’t smoke cigarettes but
you also talked about the 200,000 lives that might be saved if everyone achieved
a high school education because education is so strongly associated with health
and well being. How do you see the results of your research being used in public

policy beyond health care per se but really to influence the public policy as we
look at things like education policy in this country?

Dr. Nicholas Christakis: Well, I think the data that you are summarizing first of all
to be clear is the work of other people that I was describing, that’s not my own
work. And I think there, what you are describing is a kind of shifting perspective
so usually when we think about the causes of death in our country, you think
about cardiovascular disease as the leading cause, then cancer, then you have a
variety of other causes sort of neurologic diseases, pulmonary diseases, various
infections, pneumonia I think is number five on the list and so forth. And you go
th
down the list of top 10 causes, Alzheimer’s I think is 10 on the list and you get
some list of causes of death by disease. But actually you can think about causes
in a completely different way. You can think about causes in terms of the
underlying or root causes and here now we would emphasize things like tobacco
exposure. Tobacco is the leading preventable cause of death in our society;
about 400,000, 440,000 people die every year not just from lung cancer but from
other cancers, from burning to death from inhaling second hand smoke of other
people. Then you can go down the list alcohol exposure, sort of occupational
injuries, environmental toxins and socioeconomic risk factors. It invites you to
begin to think about different priorities for how we go about combating illness in
our society which in turn will invite you to think about different ways of allocating
resources. So instead of spending money let's say to do research on different
kinds of cancers or neurologic diseases in that way, you might want to spend
money understanding the behavioral determinants of your health. I think we
spend less than 5% of our research as a country understanding or studying
causes the second way I described you and 95% of our research dollars I am
pretty sure are spent studying causes in the first way I described you of thinking
about causes.

Mark Masselli: Dr. Christakis, while socioeconomic variables can play a role in
disease, in health as you have demonstrated so can one’s social network. You
have also been able to shed some light on how social factors can positively
impact health. Can you tell us about your work on how groups can drive down
smoking rates as well as how happiness spreads socially?

Dr. Nicholas Christakis: Yeah. I think it’s important to understand that I mean
there are two ideas there buried in that question. One ideas is because people
are connected, their health is connected and the reason we connect to each
other is because the benefits of a connected life outweigh the cost. If I was
violent towards you or made you miserably unhappy or infected you with bad
germs or gave you bad health habits or give you misinformation, you would cut
the ties to me and the network would disintegrate. Therefore the spread of good
and desirable things like ideas, like information, like happiness, like kindness, like
love even are required to sustain and nourish the network. So the reason people
stay connected to each other, in fact the reason we as a species form networks is
that the benefits of a connected life outweigh the cost.

So yes, we are harmed by our links to others but yes, even more we benefit from
our links to others, and this has been shown in numerous ways with numerous
study designs. And one summary thing to understand is that the more socially
isolated you are, the higher your risk of death. So first of all on a very kind of
30,000 foot level being socially isolated is not so good for you. The second thing
that you alluded to, which I am not losing the thread, how can you use these
things. So there are number of ways that you can begin to think about exploiting
the understanding of human connectedness to enhance or help and the simple-
minded way would be just to realize that your isolation is not good for you but
there are more sophisticated ways as well. So for example we know that group
level interventions are more effective than isolated interventions.

So to pick a simplistic example imagine you have $100 and you are trying to get
10 smokers to quit smoking. You could bring them in one at a time and spend
$10 on each of them and perhaps of the 10 one of them might quit or you could
bring all 10 of them in together and put them in a group and you spend $100 on
them at once and perhaps three of them might quit because now they can
reinforce and support each other. So with the same 10 people, the same $100
you get three quitters instead of one quitter. This is an example of the ability of
group level phenomena and social network phenomena to provide positive
benefits and to be used in a kind of public policy way. And we have many
examples of this now, both old examples things like Alcoholics Anonymous and
Weight Watchers and so forth, which are kind of artificial social networks and
much more sophisticated bigger and sort of more complex examples nowadays
using different kinds of networks.

Margaret Flinter: So Dr. Christakis, I am going to maybe pull that thread a little
further in 2010 TED Talk. You suggested that it isn't just what we are saying and
doing that affects the people we are connected to in our social network but it’s
actually the very shape of that social network that has an effect on us. You
talked about the differences between being at the edge of the network or at the
center of the network with lots of connections and you can pair this, you make
the analogy to the organization of carbon atoms that can produce both graphite
and diamonds and you suggested that new properties actually emerge because
of the structure of the network. Can you go into little more detail for our listeners
about how this works and what it means?

Dr. Nicholas Christakis: Yeah. So when you think about our embeddedness in
networks or interactions with others, there are two broad ways we are affected by
this, one is what we call, what James Fowler, my colleague might call contagion
and the other is what we call connection. And contagion is given the structure of
a network what’s flowing across the network, you know are germs flowing across
the network, is information or gossip flowing across the network, how are we
affected by things happening to other people to whom you are connected. When
we think about connections on the other hand what we are focusing on now is

the actual structure of the ties. It's not what’s flowing across those ties that might
matter. So a simple example of this might be the difference between having two
friends and four friends and ten friends. So it's not what those friends are doing
that we are focused on it's how many friends you have. And the example we use
to try to bring this point home is the difference between graphite and diamond;
both of those have as their constituent elements carbon atoms, and the graphite
is soft and dark and the diamond is hard and clear which properties you get
depends on how you connect the carbon atoms to each other. And so something
similar can happen with human beings, you can take the same people and
connect them one way and they have one set of properties or connect them
another way and they have a different set of properties. And this is what we
mean by how connection can affect us; if you assemble human beings into
particular networks or they naturally assemble themselves this way, they go on to
display certain particular kinds of characteristics and the people within those
networks can be affected by those characteristics.

Mark Masselli: This is Conversations in Health Care. Today, we are speaking
with Dr. Nicholas Christakis, who researches how social factors affect health,
health care and longevity. We operate a community health center here in
Connecticut and provide care to about 130,000 patients and provide that sort of
traditional primary care services but we also run a dance hall and run community
gardens and farmers markets and we find that such an incredible benefit of
connecting our communities together. Based on your research, what sort of
community building and community activities do you think cities across the
country should be engaged in to have a greater impact in using social networks
to promote health and do you have any examples of that?

Dr. Nicholas Christakis: Well, I think what you are highlighting now is the power
and relevance of formal institutions to facilitate and foster social interaction. So
suppose we realize that first of all human beings naturally form networks by and
large, we are not just social animals we are actually network animals. But there
are also ways in which the kinds of formal institutions we create whether they are
community gardens or national governments, affect how we interact with each
other and of course there is important role of culture, right. I mean some cultures
in which people might reside are much more welcoming or sort of open or
encourage more interaction and others are more suspicious and discourage
interaction. Here I am speaking across societies across the world. So the kinds
of formal institutions that you outlined are very important and valuable in the kind
of creation of social types. The classic example of one of the most well-known
scholars emphasizing this approach is of Putnam, the author of Bowling Alone,
who talked a little about the classic example of the parent-teacher association
and the role they played in our communities in connecting people to each other
who had similar concerns, kids into similar age and how those ties because of
the existence of those institutions, the PTAs were created and supported. And
we can have other kinds of institutions in our society nowadays like the ones that
you alluded to.

Margaret Flinter: Dr. Christakis, your work has been constantly evolving as has
technology and also are ideas about social networks. And much of what you
have been saying about social networks has been applied to personal face-to-
face as you said old fashioned befriending, the real person in front of you; the
network’s still an enjoyable way to have friends. But more and more certainly
when people hear the phrase “social network” they are thinking about the online
social networks and there is a great deal of interest in using online social media
as a way to track health, influence health, even track the spread of diseases.
One of our recent guest Dr. Mostashari from the Office of National Coordinator
spoke about monitoring public health using social media but beyond monitoring
this also using it to influence and promote it. So as these social networks
become more powerful what’s the effect of that technology on us as another form
of networking?

Dr. Nicholas Christakis: Well, most people when they think about sort of online
network think of the risks or dangers of the mere use of these networks or worry
that people ____ 16:32 face-to-face interactions or that people will become
addicted to the Internet and so forth. But the question you are asking, it’s
important for people to understand it's different than that, the question you are
asking is to what extent is the availability of this kind of data about where people
are situated in the network and what’s happening to them, how does that affect
the ability of public health officials and others to monitor the population and track
and follow and understand what’s happening. And the answer is it's providing us
tremendous new tools. You can get early warnings about epidemics for example.
In the olden days, you just had to wait for people to go to the doctor’s office then
the doctor would do some test, those tests the results would be sent to some
kind of central monitoring facility, weeks later we would know what’s going on in
terms of the health of the population. Whereas now, people could literally
monitor what’s happening online amongst millions of people that are updating
their Facebook status for example and there is an enormous, enormous effort
being made amongst scientists right now to figure out how valuable, how
realistic, how quickly might we exploit information of this type. And I think over
the coming years we are going to see many new tools that take advantage of
online data that allow us to better meet the health needs of the public.

Mark Masselli: Dr. Christakis, talk to us a little bit about the next wave of your
research in the area and are there folks engaged in translational research based
on some of the work you have done and also give us little peek at maybe what
some of your students are thinking about, or writing about and researching as
well?

Dr. Nicholas Christakis: What my lab is doing along with my colleague James
Fowler’s lab, we are engaged in three sorts of major things right now. One thing
is we are seeking to understand the biological origins and biological
consequences of networks like why do human beings form networks in the first

place and we understand this from an evolutionary biology perspective are there
sort of genetic foundations of human social interaction. The second set of work
is doing experiments with networks and we think this is an important new area
moving beyond observational studies and moving to do actual experiments
where we can be a bit more confident about what’s actually happening. And the
third thing we are doing is we are trying to start applying some of these
techniques, can we increase the likelihood that villagers in Uganda will use
bednets to prevent malaria, can we find influential individuals in the network and
influence their behavior in a way that gets more people to use bednets or we
understand the resistance in communities in India to using certain neonatal
health practices. Maybe there are pockets within the networth where people are
resistant and if we understand how networks work, we can deliver these health
care interventions in a more efficient and effective way.

Margaret Flinter: Dr. Christakis, this also builds off of that a little bit. On the
show we don’t usually dive too deep into the science but I think you have laid out
some just brilliant descriptions of how we move from our essential genetic
makeup, our genotypes to how we express our genetic makeup our phenotypes
to how we might ultimately not in a day but overtime influence the genetic
makeup of others in our community or be influenced by them. Can you maybe
share with our listeners an example of that or just turn that into kind of everyday
language for our listeners?

Dr. Nicholas Christakis: Well to be clear, I didn’t just say that your behavior
affects other people’s genotypes. It’s not like your behavior will affect someone
else’s gene at least not in real-time. We have been exploring that idea over
beyond that is to say over tens of thousands of years can we find evidence that
people’s social interaction is affecting the actual genetic constitution of human
beings. And there are a bunch of scientists working on related topics right now
and the answer to that seems to be yes that a culture can affect our genes and
one of my favorite examples of this is the persistence of lactase in adults, the
ability to adjust lactose in adults that is a valuable ability and that’s a mutation,
that’s a valuable ability only once human being has evolved a capacity to
domesticate milk producing animals. And what’s been found is that over the last
3000 to 9000 years there have been several cases in which human beings have
domesticated milk producing animals and then that seems to have led to a
selection pressure whereby the people who take advantage of this milk grew in
number compared to people who could not. And so this is one of my favorite
examples of how culture can change our genes. What we do to the world can
feed back and affect us at a very deep level. But your other sort of the broader
way that you asked the question was to what extent can we connect everything
from the microscopic biological level to the macroscopic policy level. And I think
that’s an aspiration that many scientists hold is that with better understanding at
every level we can integrate across levels and really understand not only what is
happening but understand how best to intervene in the world to make it better.

Mark Masselli: Dr. Christakis, we like to ask our guests this final question. When
you look around the country in the world what do you see in terms of innovation
and who should our listeners at Conversations be keeping an eye on?

Dr. Nicholas Christakis: My goodness, there are lots of people doing very cool
things. There is a guy at NYU right now Sinan Aral who is doing some very cool
things looking at online networks. There are some people, Nathan Wolfe at the
Global-Viral Forecasting Initiative in California and his group are doing some very
cool things. There are just so many scholars that are doing what I would
consider to be very exciting work, it’s hard for me to pick those. I am sure I am
neglecting all my other friends because I wasn’t expecting that question. Those
are just two people that popped into my mind right now.

Margaret Flinter: Well we expect everybody in your social network to be
fascinating people so I am sure there is lots of opportunities to focus on them.
Today, we have been speaking with Dr. Nicholas Christakis known for his
research on social networks and the social factors that affect health and health
care and longevity. Dr. Christakis, thank you so much for joining us today on
Conversations on Health Care.

Dr. Nicholas Christakis: Thank you for having me.

Mark Masselli: Each week Conversations highlights a bright idea about how to
make wellness a part of our communities and everyday lives.

This week’s bright idea comes to us from Kansas City where urban farmers are
thriving because of an unusual partnership between refugees and local farm
programs. In Kansas, several refugee families from Africa and Asia live in a
public housing project called Juniper Gardens. When the refugee women from
the community began asking Catholic Charities of Northeast Kansas City for
garden, an opportunity arose. Catholic Charities quickly partnered with the
Kansas City Center for Urban Agriculture to start the new roots for refugee farm.
The program has been operating for over 5 years. The farmers receive a quarter
acre plot after a commitment of at least one year with the community garden.
Everything is paid for including seeds, tools, and water; in the winter, farmers
take courses in planting, production and marketing. For many in the participating
refugee community, farming is what they know and what they are good at. In a
new and unfamiliar place it not only offers them a sense of self determination but
healthy food for their families, extra income, a way to settle into their new
community. The Health Care Foundation of Greater Kansas City which provides
some of the programs financial support interviewed one woman who used to be a
farmer in her homeland of Burundi.

Voice: This garden is everything I have. This is the only thing I know in America
so if I don’t have my farming or my gardening I don’t know what I will do.

Mark Masselli: Gradually the farmers take on more responsibility and ownership
of the land. Then they go on to run independent farm stands in the community
which enhance the local food system. Helping refugees establish a new way of
life that’s healthy, sustainable, and connected, now that’s a bright idea.

(Music)

Margaret Flinter: This is Conversations on Health Care. I am Margaret Flinter.

Mark Masselli: And I am Mark Masselli, peace and health.

Conversations on Health Care, broadcast from the campus of Wesleyan
University at WESU, streaming live at www.wesufm.org and brought to you by
the Community Health Center.