Why we should adopt a "zoobiquitous" approach to health

We are all animals. It's a fact that may be unsettling for some, but for others it is a fountain of understanding and of inspiration. Since 1859, thanks to Charles Darwin, our place in the animal world has been firmly established. Yet, to this day, it is all too common within medicine (and nutrition) to have the tendency to develop a narrow-mindedness about ourselves that disconnects us from the natural world. Rarely do medical doctors ever look beyond, to other animals, for a broader perspective about their fields. As the veterinarian insider joke goes, "What do you call a physician? A veterinarian who can only treat one species." 

 This is where zoobiquity (a different, zoobiquitous approach to medicine) comes in.

What is zoobiquity? When a story of how two obese Alaskan grizzlies lost hundreds of pounds helps inform nutritionists about how they might advise their human patients on weight management, you could say that is an example of zoobiquity. When a psychiatrist finds she is able to kindly comfort a patient diagnosed with anorexia by pointing out that an eating disorder is nothing ashamed of and that, in fact, it is quite common across several species, that's zoobiquity. And, when a veterinarian oncologist and human oncologist come together to discuss the similarities of their animal and human patients and share data in an effort to improve medical outcomes of their patients, that's zoobiquity.

The term, a merge of the words "zoo" and "ubiquity," was coined by UCLA cardiology professor Barbara Natterson-Horowitz, M.D., and science journalist Kathryn Bowers as a way to describe their call for a coming together of three scientific fields: human medicine, veterinary medicine, and evolutionary biology. The duo also used the word as the title of their book, Zoobiquity: The Astonishing Connection Between Human and Animal Health, the paperback version of which has just gone on sale today. I highly recommend you purchase a copy to read even if you are not necessarily interested in medicine; the book is still worth the read because of what Bowers calls "cocktail party fodder."

In the book, for example, you'll learn all sorts of interesting facts: that dinosaurs also suffered from cancer, that fish faint, that horses suffer from sexual dysfunction, that all sorts of wild animals can at times develop eating disorders or overeat and become obese, that koalas suffer from chlamydia, that birds self-injure, and that wallabies get stoned. A passage that best sums up the message of the book is this one about breast cancer resulting from a genetic mutation of the BRCA1 genes that is shared among different species: "When it comes to breast cancer, a jaguar originating in South America and an English springer spaniel in Sweden might be medically more relevant to an Ashkenazi Jewish woman than her next-door neighbor is."

What led me to read the book was a long-held fascination with the topic of how health in the animal world relates to the human world. Because of my interest, I sought out a conversation with the co-authors and, now, I'm delighted to offer you this interview from last Sunday:   

Edited interview with Zoobiquity authors

DESPAIN: How did you come up with the term, zoobiquity?

DR. NATTERSON-HOROWITZ: We had been thinking a lot about all these overlaps from everything from cancer and heart disease to obesity to eating disorders in adolescence. We were looking for clinically relevant points of intersection that brought together human medicine, veterinary medicine, and evolutionary biology. And we found ourselves really struggling to describe it not only other people, but for our own purposes. There wasn't really a word that would describe bringing these three fields together. So we decided to coin our own word. We tried to find a word that brought together elements we wanted. So, "zoo" and "ubiquity"  became "zoobiquity."

DESPAIN: What's your favorite example of zoobiquity?

BOWERS: I'm really interested in the shared physiology that we have across species. That seems in some ways the lowest-hanging fruit, that we share blood and bones and other physiologic systems with other animals. I've been really interested in the crossovers in the psychiatric realm, how animal behavior and human psychiatry have more in common than we thought. What in humans we might call a mental illness, or eating disorders, or anxiety, or obsessive-compulsive disorder. In our book, we have examples of self-injury. If a human was exhibiting this, they would be taken to a psychiatrist. We think of them as maybe being part of our human cultures, but they're actually shared with other animals because the roots may be even deeper in mechanistic or physiologic areas that create behaviors seen across species.

DR. NATTERSON-HOROWITZ: When psychiatrists typically think about problems like cutting, or anorexia, or bulimia, there's a tendency to think about those problems in a pre-frontal cortex capacity. Psychotherapists use language to access those symptoms and to treat them with talking therapy. The idea that animals would share these in the first place required us to take a little bit of a step that's longer than what we typically do when we think about animals.

DESPAIN: One of the chapters in your book is about the "Fear of Feeding". This is related to what you're talking about.

DR. NATTERSON-HOROWITZ: If you look at the fear of feeding or of eating disorders, you find that psychiatrists will tell us that, in human beings, most patients diagnosed with an eating disorder will also have an anxiety disorder. It's common to have a comorbic psychiatric condition if you have an eating disorder. So if an anxiety disorder is extremely associated to eating disorders, what does that tell us? Well, it suggests that there's something about eating that connects to fear. And, you start looking at connections between fear and eating in the animal kingdom and it becomes very clear that an unsafe environment absolutely affects animal eating behavior. We have examples of that: an environment that has a high density of predators where there's a lot of risk, prey animals may restrict the amount they eat, the time they eat, perhaps the range of where it eats. When the predatory threat is reduced, the animal is more relaxed and the animal gets fatter, because the animal eats over a greater period of time. When you look at a human patient with anorexia, when they're in the throes of the disease, when they are  extremely anxious, you see their eating is highly restricted. As the treatment continues and is hopefully successful, and as anxiety is reduced, there's this loosening up, a relaxation of eating. We think that parallel speaks to this highly conserved neurophysiologic system, whether it is the autonomic nervous system, or whether its mammalian or even pre-mammalian, it really suggests these are highly conserved systems. This is a new way for psychotherapists and psychiatrists to think about these eating disorders in human patients.

BOWERS: Barbara has mentioned predatory stress, but there's even the idea of social stress. Social stress can affect animals and their eating either by where they are in their social hierarchy or almost by the way they need to behave. We were just talking with Iain Couzin who was giving a lecture at UCLA and he was describing locusts swarms and how big a deal cannibalism is in the way that those animals organize their group behavior, so even just putting something like eating and social movement in the same arena, I think, really opens up what a human nutritionist might be able to think about when counseling a single human being.

DESPAIN: Being a nutritionist, one of my favorite chapters in your book was Fat Planet where you tell the story of two obese Alaskan grizzlies Jim and Axhi who were treated at Chicago's Brookfield Zoo by nutritionist Jennifer Watts. Watts changed their diet and lifestyle in ways that was informed by knowledge of their natural ecology. It wasn't a "perfect wild diet" -- as that's fantasy -- but there were changes like considering the environment's cyclical periods of abundance and scarcity as well as season's effect on their intestinal microbiomes. Previously, I've written about nutritionists doing similar things both with lemurs and Komodo dragons that suffer from obesity and diabetes. What would you say are the key takeaways in dietary advice that humans can learn from your examples?

DR. NATTERSON-HOROWITZ: There were so many surprises that we encountered in researching the book. One early misconception that we bumped up against was this idea that only human beings overeat. There seems to be this fantasy that animals in their natural setting have internal regulatory systems that would result in eating only to satiety and that would be it. This idea was so wrong. We now understand that, actually from an evolutionary perspective, animals are likely to encounter periods of scarcity. And, when they encounter periods of abundance, they are going to absolutely overconsume and sometimes spectacularly overconsume. That was already the beginning of a set of really surprising findings. If there's abundance and there's no predatory threat, they'll just consume and consume. The other real biggie was that (and I went to medical school and, for 20 or 25 years, have been practicing medicine), I've seen a lot of overweight and obese patients; it's pretty much been assumed until very recently that it was all about calories in, calories out. I think most physicians have had patients that say they are not losing weight, and they swear to you that they're eating 900 calories a day -- do you really think that that's true? I think most physicians would be skeptical and think that their patients are probably not telling the truth or not aware of how much they're eating. So one of the exciting and surprising aspects of researching this chapter was to learn about all of these other factors that go beyond calories in and calories out. These could very well be influencing metabolism in both individual human patients and other species as well -- things like the seasonal microbiome, and circadian variation, even climate change, endocrine-modifying chemicals, and perhaps antibiotics in the environment. These are really interesting ideas to think about even in [the context of] the obesity epidemic as not being isolated to human beings, but perhaps being more species-spanning.

BOWERS: Even the approach that a physician or nutritionist might take with a human being, we think might be expanded and informed by the way veterinarians treat their animal patients. Because a veterinarian is not usually  going to treat their patient as an individual, but really going to look at them as part of a group in an environment -- that's the social environment built around the animal.  In human medicine, we put a lot of it on the patient -- you're eating too much and you need to exercise more. A veterinarian would really think about what's going on around the animal that makes them overconsume.

DESPAIN: Gut length variability throughout the season was something I'd never heard of until I read your book. I found that fascinating.

BOWERS: We were pretty intrigued by that also. We were really interested in the idea that gut length could vary seasonally in the same animal. It can lengthen and expand.

DR. NATTERSON-HOROWITZ: Kathryn and I had a lot of these fun moments. If you take a look at the human small intestine, and even if you look at the colon, you see this ribbon of smooth muscle. What is that smooth muscle for? Yes, it's involved in peristalsis [intestinal movement], but perhaps there are factors involved in lengthening and shortening the gut. Even if it was only 5 to 10 percent that would be quite significant over a long period time. Then again, the overarching point of the book is to look at a human patient as a human-animal patient and think of them comparatively, which is not something that we learn about in medical school these days.

DESPAIN: You say that working with veterinarians changed how you practiced human medicine. What do you think medical doctors can gain from this perspective?

DR. NATTERSON-HOROWITZ: You know, it's funny, people have asked the question in a different kind of way. Why is there resistance? What are the barriers? What is the benefit? Is there a benefit? Is there a way to teach medical students in a better way and will they be better doctors? Will this result in the creation of new hypotheses that will lead to new knowledge The answer is that we believe that they will. These are early days so there are only a couple of areas where we've seen leaps from this approach and we expect there will be more. There really have been two areas where there has been quite a lot of work done. The first is in the area of cancer research. The National Cancer Institute, about 10 years ago, started the comparative oncology program. And that program is looking at cancers that occur spontaneously in humans and mostly dogs and cats (companion animals). We're talking about osteosarcoma, which is a very serious bone cancer that affects adolescents and large-breed dogs. The biology of the cancer is very similar between the two species. There's a lot that can be done to understand tumor biology and clinical course by looking at dogs. If you just look at oncology, there's been real advances through a comparative approach. The other area where human medicine can absolutely benefit, through the lens of evolutionary biology, is the issue of antimicrobial resistance. There are some excellent and fascinating models that look at the emergence of resistance in an evolutionary context. At UCLA, we, as well as a chairman of evolutionary biology, started a program in evolutionary medicine and we had a wonderful speaker, Andrew Reid, that is talking about trying to evolution-proof antibiotics. So, there's many areas around this issue of infection and antibiotics where we can gain from working collaboratively with the veterinary world.

DESPAIN: What do you think is a benefit from a patient's perspective? For example, I have joked in the past that the real reason why I decided to become a nutritionist and never pursue medicine is because I faint at the sight of blood or even when someone draws blood from me -- I've found this incredibly annoying. Now, from your book, I've learned that I share that phenomenon with several animals including fish and perhaps it may even have a protective effect in survival terms -- beyond the fight or flight response. Do you find that your patients find comfort or understanding in knowing they share their circumstances, say like cardiovascular disease, obesity, or cancer, with animals?

DR. NATTERSON-HOROWITZ: It really varies. This message really resonated with us. The fact that animals can self-injure, get addicted, get obese, get anorexia nervosa, or have self-induced vomiting -- I think for some patients it can be profoundly de-stigmatizing. There's this kind of human grandiosity that our disorders are human disorders and that we are so uniquely disordered. That we have this spectrum with other animals is very humbling, very connecting, very destigmatizing, very deshaming. For some patients, it might not have that affect, but for some I think it has.

DESPAIN: Your book has been out a year now. How do you think your approach has been received? I see there's now an annual conference. What kinds of people turn up at this event?

BOWERS: We're having our third conference this fall. It's a place where we are really trying to make this happen. We're putting out a rallying cry. The conference is for working physicians and working veterinarians and we're really excited about the next one. It's going to be in New York City with faculty from Cornell, and NYU, and the Bronx Zoo. There's one group that has understood it from the very beginning: that's the veterinarians. But we're starting to get the message out to physicians as well and even general patients. We also get letters from general readers, and teachers, and its bolstering their interest in biology and evolution.

DR. NATTERSON-HOROWITZ: It's fun because we have an auditorium full of half Ddms and half MDs, all very prominent academics. On stage, we've had a veterinarian oncologist and then we've had a human oncologist. And the veterinarian comments on the human case, and the human oncologist comments on the animal case. We also did that for heart disease. Then, everyone grabbed boxed lunches and we went on "walk arounds" (like in a teaching hospital) at the zoo. We had the veterinarians there and we were trying to make the point that we're all doctors. So we wanted to start the conversation.

DESPAIN: Barbara and Kathryn, thank you for your time.

DESPAIN: I found Zoobiquity a lot of fun to read, extremely entertaining, and also offered plenty of useful facts I can use to entertain with at a party.

BOWERS: Cocktail party fodder!

Photo credits: Wikipedia.