The connection between coral reefs and human health

February 21, 2019 — Coral reefs aren’t just beautiful. They’re the most biologically diverse ecosystems in the oceans, and can provide food, jobs, and protection from storms for coastal communities. But reefs around the world are under threat from a variety of a factors including environmental changes, pollution, and overfishing. And that could have major implications for communities that rely on these reefs for the seafood that sustains their diet.

A new research project is trying to tackle that problem by taking an in-depth look at the health of coral reefs in the South Pacific island nation of Kiribati. In this week’s episode we’re speaking to Christopher Golden, the scientist leading this four-year project. Golden is an assistant professor of nutrition and planetary health at Harvard T.H. Chan School of Public Health and associate director of the Planetary Health Alliance. Golden and other researchers will examine the factors affecting the health of reefs in Kiribati, identify fisheries management strategies that can promote healthier reefs, and gather nutritional data from residents to understand how changes in the health of reefs can affect the health of people living nearby.

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Read more about Christopher Golden’s research project on Kiribati

Watch videos highlighting Golden’s previous work in Madagascar

Full Transcript

NOAH LEAVITT: What is the connection between coral reefs and human health, particularly when it comes to nutrition, what we’re eating, our diets?

CHRIS GOLDEN: So in many parts of the world, local communities are heavily reliant on coral reefs for the types of fish, seafood, and shellfish that they’re eating. And so when it comes to delivering key micronutrients like iron, zinc, vitamin A, vitamin B12, fatty acids, they really rely on those types of seafood resources for their nutrition. In parts of the developed world, we might not be as reliant on coral reef resources because we get our fish from pelagic fish resources or deep sea fish resources that then are traded through markets. Or it’s produced through aquaculture, from fish feed that then is redirected to kind of wealthier developed country markets.
So there are fundamental differences in the pathways by which people have access to seafood. But coral reefs are really critically important in the hundred or more countries where they are present. So some of the recent work that I’ve been doing has been looking at the importance of these types of coral reefs in the South Pacific specifically.

NOAH LEAVITT: And I’m guessing one of the concerns is that climate change is kind of hastening the decline of these coral reefs. So what’s the connection between climate change and the health of these reefs themselves?

CHRIS GOLDEN: So with climate change, there are multiple different impacts on fishery systems. So one impact that you will see is that as ocean sea temperature rises, fish will move from the equator toward the poles. And so what you see is an enormous decline and reduction in fish catch along the areas of the equator. And it’s predicted to decline by around 50% by 2050 in comparison to what we are seeing today. And so those fish will be moving poleward from the equator, so both north and south.
The other ways in which this has impacted are through sea temperature rise and ocean acidification that can really harm coral reef habitats. And so this could be driving coral reefs into coral bleaching, which is a kind of common phenomenon that many people have heard of now, where the coral is bleached. That key kind of foundational habitat for coral fishes then is no longer able to sustain those fish populations. And the stock of those fisheries rapidly declines, meaning that there’s less seafood available for local consumption.

NOAH LEAVITT: And so I know you just received this grant to study coral reefs in the South Pacific. So can you tell me what this project will focus on? And then how did you kind of arrive at kind of wanting to investigate this question in this particular location?

CHRIS GOLDEN: Let me start with that second question, because I think it sets the stage for the type of research that we’re doing. We see that across the world, the rapid decline of fisheries will be destabilizing food security and impacting human nutrition in a variety of ways. We think that there are roughly three typologies by which countries might be affected.
So you have countries like the US, New Zealand, Japan, Sweden, where a local collapse of the fish stocks might not lead to massive changes in the diet. It could change the price dynamics. It could change what species are available in markets. But for all intents and purposes, those who were eating fish before will continue to eat fish. And those who were not eating seafood before will continue not to do so.

You then have a type of country like Madagascar, Gabon, Suriname, where a collapse of local fisheries resources will lead people into kind of more vegetarian diets because domesticated meats or wild meats are prohibitively expensive. And so in those cases, you have increased micronutrient deficiencies, deficiencies of iron, zinc, vitamin A, vitamin B12, that are driven from a lack of access to animal source foods.
These types of countries have heavy infectious disease burdens. They very often do not have fortified or biofortified foods. So they need more micronutrient nutrition and are getting less. And so that presents another type of problem.

There is then a third case where countries like Indonesia, Mexico, Brazil, small island developing states of the Pacific, will have a collapse of their local fisheries and then will experience an acceleration of the nutrition transition. What this means is that they will move very rapidly into obesity, metabolic disease, diabetes, because they are losing access to their traditional diets and moving into a Western diet of processed foods, fast foods. In the Pacific, you are eating things like ramen, white rice, Spam, turkey tails, mutton flaps. So it’s all of these things that really are harmful to one’s health and one’s body.

And so that context really provided an interesting lens for me. I’ve worked for nearly the past 20 years in Madagascar, doing research. That’s clearly one context that is very much a context of chronic undernutrition.
I became very interested in looking at parallels and contrasts within the South Pacific. And so we started this research project in Kiribati. It’s a partnership between the Harvard School of Public Health, University of California, Santa Barbara, working with Doug McCauley and Jacob Eurich, and a partnership with University of California, Santa Cruz, working with Katy Seto, who is leading our governance research. And Jessica Gephart from the National Socio-Environmental Synthesis Center is also involved with the project.

And what our team is jointly doing there is working across the country of Kiribati, which is a remote island nation in the South Pacific. There are roughly 30 different islands that are independent and isolated islands, each with their own fisheries governance systems, each with their own methods of either netting, fishing, trapping, to varying degrees of damage on the coral reef.

And what we want to understand is to what extent does fisheries management improve or degrade the health of coral reefs? And to what extent does the condition and health of coral reefs enable access to seafood resources for local populations, thereby accelerating or stalling the nutrition transition? So nine out of the 10 most obese nations on Earth are found in the South Pacific. Kiribati is eighth. I think they have roughly 50% of their population is obese. And so it’s a really critical issue in these types of countries to find ways of reconnecting with their traditional diets to try to slow some of what we are seeing in terms of an obesity epidemic.

NOAH LEAVITT: So it’s interesting. Because you’re really looking at the health of the reefs. But then on the flip side, you’re looking at the health of the people. So you’re kind of looking at it from both angles.
CHRIS GOLDEN: Exactly. We’re really trying to understand how healthy reefs can serve as a nutritional delivery mechanism to improve the health of people.

NOAH LEAVITT: And as you mentioned, you’re building off some of your previous work in other areas. But has there ever been previous research, looking at this specifically, kind of the connection between reefs and human health? Is there existing research that you’re working from?
CHRIS GOLDEN: Absolutely. So this type of work has happened both on land and sea. Where I got these ideas was thinking about the ways in which bushmeat, quote, unquote, consumption– so the consumption of wildlife and wild mammals for food– would contribute to food security and nutrition. So my past research in Madagascar definitely was a natural example for how to do this research on coastal systems, the ocean, and fisheries, and food security.

There are also several other research groups who have been looking at this extensively. And so there is a body of researchers that look at the role of marine protected areas and marine conservation and delivering nutritional benefits, fisheries management, and delivering economic livelihood, nutritional benefits. What we are doing that is unique is trying to measure not only the health of coral reefs and the amount of consumption of seafood that people are experiencing, but we’re also going down to the levels of measuring the actual nutritional biomarkers.

So we are measuring hemoglobin to look at anemia. We’re looking at hemoglobin A1C to measure diabetes. We’re looking at fatty acid profiles. We’re looking at a variety of different markers that will allow us to truly understand this pathway that leads from healthy reefs to healthy people in a very unique system in Kiribati, where we have almost a quasi experimental design because there are nearly 30 islands where they are independent, isolated, remote, maybe one flight a week between each of them in the capital, which then only has two flights a week to Fiji. I mean, this is a very, very remote place. We’re really able to look at this as a kind of natural isolated experiment on how fisheries management can influence nutritional delivery.

NOAH LEAVITT: And would one of the goals be, I guess, to say, OK, this management style used on this island, and this maybe is a model to use elsewhere, maybe in the South Pacific, but maybe in other kind of reef areas? Do you think the findings to be applicable elsewhere?

CHRIS GOLDEN: Absolutely. So what we are hoping to do is we have begun a partnership with the University of Wollongong in Australia and something called the Pathways Project, which is being led by Neil Andrew. And what he and his team are doing are setting up a bunch of different sites to help with community-based fisheries management to see if that could serve as a model system to improve nutrition. And so our study design includes these aspects of kind of community-supported conservation efforts to see if that form of stewarding their natural resources can actually help their nutritional outcomes.

NOAH LEAVITT: I mean, you talked just a minute ago about this idea of kind of getting people to kind of return to maybe these more natural kind of eating habits. I’d be interested to know, how does the work you’re doing kind of fit into the work of your colleague, Sam Myers, which has shown that climate change could make crops less nutritious over time?
So it seems like people are potentially getting hit from both sides, where they might face less nutritious crops. But their historical traditional diets are also being affected. So how are you kind of at the Planetary Health Alliance working to balance all those different potential harms to nutrition?

CHRIS GOLDEN: Absolutely. So the work that Sam has done has been critical in understanding that many of the things that we think we can rely on for nutrition might not be available to support us in the same way, moving forward into the future. The case of Kiribati is a bit unique in the sense that there is no elevation above seven meters in the entire country. There is very, very little soil. Agriculture in the true sense of the term doesn’t really exist there.

So people are relying on coconut, pandanus, taro, and seafood. And seafood is really this critical mainstay of their diet. And the other things that they’re getting are really these processed foods that are subsidies from Australia, New Zealand, et cetera. That’s heavily processed food, very unhealthy. And so it’s a decision between traditional diets and these highly Western processed diets, which really makes it a very clear example. It’s not as much of a clear-cut case in other types of geographical or cultural contexts.

NOAH LEAVITT: Yeah. Because like you mentioned at the beginning, a country like the US, the fisheries might suffer. But there are potentially other options. In a place like Kiribati, other remote places, you just don’t have any other option.

CHRIS GOLDEN: Absolutely. I mean, in the US, you can be a vegetarian and be completely healthy because of the way that our health system works, because of the lack of an infectious disease burden, from fortification, biofortification, vitamins, and supplements. In the developing world, particularly in the tropics, with a heavy disease burden, people do require certain amounts of animal source foods, including seafood, to provide them with certain types of nutritional sustenance. And so without that, it really becomes problematic.

NOAH LEAVITT: I guess broadly when it comes to fisheries management, I mean, I think the research seems to indicate that eating seafood, one, is good for our health. It’s probably good for the environment. So how do you balance kind of encouraging people to eat more seafood, eat less beef, which may be more harmful to the environment, but also still protecting fisheries? I mean, I imagine it’s difficult because there’s all sorts of different geographic specifics. But is that something that people in your field are concerned about?

CHRIS GOLDEN: Absolutely. There was just the release of the EAT-Lancet Commission on healthy, sustainable diets. That came out roughly two weeks ago now. And this document outlines what a healthy diet looks like for different regions around the world. And it’s a critically important document because it allows us to look at where we are now and where we should be and how to actually operationalize the shift in diets.
I don’t think anyone who is truly thoughtful about these issues would say that we do not need to reduce our red meat consumption. This is something with a very heavy carbon burden and something that is clearly not healthy for us in very large quantities. What we have with seafood is that it’s a very healthy source of animal source foods. And it can be produced in relatively environmentally friendly ways.

So aquacultures span– much like agriculture– spans a wide variety of production systems, species, and techniques. But when it’s done properly, it can be done in a very environmentally healthy way to produce very nutritional products. Similarly, many forms of wild capture fish can be done in similar ways.

NOAH LEAVITT: As I was asking that question, I was thinking, well, is seafood probably better for the environment? I mean, is it? Or does it depend on the system being used? So I guess, what is the science in terms of seafood in relation to the environment?

CHRIS GOLDEN: As far as I understand from the literature, wild caught seafood and aquaculture across the board, no matter what type and system, is almost always better than pork, beef, and lamb production. I think some types of chicken production can be incredibly environmentally friendly and meet that kind of upper end of seafood production. But really, seafood is a very good form of animal source foods to rely on when done properly.

NOAH LEAVITT: And so given your previous research, looking at fisheries management, I mean, I guess, who’s doing it right? What are some of the examples to follow, either from maybe larger countries, larger areas, to maybe smaller geographic regions?

CHRIS GOLDEN: You know, that’s a really great question. I think that there are bright spots and examples of where this is being done incredibly well. There’s a gentleman named Xavier Basurto from Duke University who does work in Mexico that’s shown this beautiful way in which locally-managed, community-based fisheries management systems can truly rebound fisheries stocks and fisheries catch in these communities with major impacts on livelihoods, health, et cetera.

There are also examples of community-based fisheries management in places like Fiji, something that Stacy Jupiter leads out there, that has shown excellent results of ways in which they’re doing this. In Madagascar, they’re beginning to do a lot of this. So Blue Ventures and other groups are looking at ways in which you can create what they call LMMAs, Locally Managed Marine Areas, to really harness the benefits of the ocean. These are still very nascent in Madagascar.

But there is a new network called Mihari, which is a development of a network of all of the different LMMAs in Madagascar to actually be in communication together. And so it’s almost the support network and community of practice where they can learn from each other across the country. And so I see enormous hope for something like that as well.
I think that across the board, they’ve seen ways in which that system of management has been very successful. But then there’s also systems of management like in Kiribati with the development of PIPA, the Phoenix Island Protected Area, and this new marine protected area in Palau or in the Seychelles where you can cordon off enormous marine protected areas and have that be incredibly successful, too, in banning industrial fishing within those limits, allowing fish to kind of spawn and regenerate, and then having increasing recruitment that then spills over into areas where you are able to make those catches.

NOAH LEAVITT: Is there a tension in terms of working with local communities, local fishermen, and maybe the messaging of there might be temporary restrictions in this area but the long-term benefits will be so great that it’s worth it? So how do you work with the local communities?
CHRIS GOLDEN: That is the ultimate challenge. So when you are working in a place like Madagascar, people are thinking of benefits in a tomorrow time frame, not in a five to 10 to 20-year time frame. And so to ask someone to make a sacrifice where they’re unable to put food on their table tomorrow so that they can gain some sort of benefit that will come in years, it puts them in a very difficult predicament. And so there needs to be ways to develop these systems of management and kind of deploy support for these communities that are experiencing this kind of momentary shortfall while they’re going through with this kind of process and evolution in management styles.

NOAH LEAVITT: So you mentioned that you’ve been doing this kind of work in various capacities for almost 20 years now, kind of this looking at how people are kind of working and relying on their natural resources. I guess, have you seen that change over time in terms of how people are relying on the ocean or on bushmeat or something like that? I mean, has that evolved over the last couple of decades?

CHRIS GOLDEN: Absolutely. I think that there has been a transition, moving people further and further away from this kind of fortress model of conservation, where you have a national park or protected area that should not be used by people to more of a either multi-use protected area system or a system where an NGO or other partner is working together with local communities to do community-based conservation management or kind of stewardship of their natural systems. And what this allows for is community empowerment to buy into how their activities shape their own fate. And I think that this type of model, although this kind of initiated in probably the late ’70s or early ’80s, has really taken off in recent years, especially within marine communities. And so I think that that is a really powerful way forward.

NOAH LEAVITT: I feel like Gina McCarthy always talks about combating climate change at this local level. And this seems like a really interesting example of that, where you are kind of starting at the local community level, like it’s not some international mandate. It really is starting at the local levels. So do you think that is kind of a model going forward, to kind of keep things community-focused, bring in local partners? I mean, is that kind of a model to be applied to other areas maybe?

CHRIS GOLDEN: I think it absolutely is the way to do it, although I don’t know if I would frame it as combating climate change. I think it’s more of adapting to climate change. So these communities are very much already experiencing impacts from climate change, and in many cases, more importantly, other forms of environmental change. So whether this is unsustainable fishing, deforestation, biodiversity loss, a lot of these forms of land use change and changes to their environment are already very tangibly impacting these communities. And climate change is also beginning to very tangibly impact these communities. And so I think that local communities see it in their own best interest to begin to change the way that they have operated and done things because they are facing a future which is quite uncertain.

NOAH LEAVITT: So as part of this larger Planetary Health Alliance, I mean, I guess that’s a really good distinction to make, that it’s not just climate change. I mean, there’s all sorts of environmental changes happening. So what’s your approach at the Planetary Health Alliance, both the work you’re doing but the work the Alliance is doing broadly in terms of helping communities adapting projects like this? But what are some of the other strategies that you’re employing?

CHRIS GOLDEN: Much of what we do as the Alliance is really around creating a community of practice. So we have not done much policy translation work to date, although many of the members that are part of the Alliance do that on a daily basis for their jobs. And so it’s really around connecting people to understand what the best practices are, cases that can be learned from, and then creating support systems for them to learn from each other and then adapt well-worn solutions.

What we really emphasize within the Alliance is that this is not just about climate change. Climate change is a very critical component of what we do. But we really need to be thinking about this broadly. It’s about urbanization. It’s about population growth. It’s about fresh water scarcity. It’s about changes in biogeochemical cycles, biodiversity laws, wildlife population collapses. All of those various forms of environmental change are having downstream effects on human health. And we really need to understand how those changes in environmental processes are leading to changes in nutrition, mental health, infectious disease, non-communicable diseases, leading to forced migration and conflict, are really changing some of the fundamental fabrics of our society.

NOAH LEAVITT: And at the end of this four-year project, in your mind, what would success look like? Are there particularly key questions that you’re hoping you’ll get answers to at the end of this four-year project?

CHRIS GOLDEN: Yeah, at the end of this project, we are really hoping that the types of connections and pathways that we see demonstrate what types of fisheries management and coral reef management practices can lead to healthier ecosystems and healthier human populations, and with doing that, to bring that back to the government so that they can share that and potentially scale it across their country. We’ve had incredible support and partnership from the Ministry of Health and Medical Services in Kiribati, just a great group of colleagues that are working there.

The Ministry of Fisheries and Marine Resources has also been great colleagues to us, the National Statistics Office, and the Secretariat of the Pacific community. So we’ve really spent a lot of time and effort working together with these key partners so that we can ensure that whatever we do find can be translated and used by the key communities that have the power to change the way that decisions are being made.