Go Wild

by John J. Ratey

  But at the same time, know that there is plenty of hard evidence that these unseen forces make a real and measurable difference in our lives, and we need not go as far afield as invisible, unsmellable phytochemicals to make the point. We also don’t perceive the ultraviolet B wavelengths of light that cause our skin to manufacture vitamin D. But it is nonetheless a fact that full body exposure to sunlight for thirty minutes causes your skin to manufacture ten thousand to twenty thousand IUs of vitamin D, and it is an understatement to say that your body needs vitamin D. Your body must have it or you will get sick.

  As we said, vitamin D deficiency is a growing problem among modern people. One nutritionist we interviewed was performing blood tests on poor inner-city children in Boston, and we thought that conversation would steer us toward talk of blood glucose and diabetes. It did. But the same nutritionist was equally alarmed by the vitamin D deficiency she found in these children. Michael Holick, an expert on vitamin D at Boston University School of Medicine, told the New York Times that on average, Caucasian Americans are short of ideal levels of vitamin D by about a third, and African Americans by about half. And many individuals are much worse off.

  In severe cases in children, this deficiency can lead to the disease rickets. But in both children and adults, lack of vitamin D can lead to increased risk of colon, breast, and prostate cancer; high blood pressure and heart disease; osteoarthritis; and autoimmune disorders. We think all of this can be headed off by simply spending more time outdoors, in the sun, which is by far the most direct way to solve this deficiency.

  Yet what is intriguing about this topic of nature is the way it seems to double back on all else we have talked about so far, so that we begin talking about our place in nature and then high blood pressure, lack of movement, autoimmune disorders, and depression all come into play. We can take this a couple of steps further. The researchers S. C. Gominak and W. E. Stumpf published a paper detailing the results of treating insomnia with vitamin D after sleep doctors noticed that some of their patients who just happened to be taking vitamin D supplements saw improvement in their sleep patterns. That led to a two-year study of fifteen hundred patients with all sorts of sleep disorders, which showed that areas of the brain with important vitamin D receptors also happened to be areas involved in allowing a positive result for the patients in the trial: sleep.

  The researchers concluded: “We propose the hypothesis that sleep disorders have become epidemic because of widespread vitamin D deficiency.”

  Here’s another crossover: remember the hygiene hypothesis—that modern people, especially urban people, are showing a rapid increase in autoimmune diseases simply because they live in a sanitized, built environment and so have removed their immune systems from the challenges of the real world? We evolved living in contact with and dealing with the full complement of microbes, and when removed from that contact, we suffer the results, especially in our internal biome. To be healthy, our internal ecosystems need to be connected to external ecosystems. We connect them by spending time outdoors, in nature, away from sterile, artificial environments.

  To be sure, there are layers and complexities to this issue beyond most of our understanding (we think some even beyond all of our comprehension), but the prescription here need not be complicated. For instance, we have long been advocates of connecting children with the natural world by ensuring that they get outdoors, dig in the dirt, and bask in the sun. The research bears out this prescription, and besides that, it sounds like fun.

  ANOTHER LEVER

  At the very least, these findings suggest some direction for public policy on such matters as greenways, trail systems, and open space, but we hope they also suggest possibilities for your own life. If a simple walk in the woods accomplishes this much alone, what about combining these benefits? What about meditation in a natural setting, or attending to nutrition and taking daily walks along the stream—and adding an adequate amount of high-quality sleep to the mix? All along, we have built the case for re-wilding your life. It almost goes without saying that part of the process ought to be some real, physical contact with things wild.

  And if a potted plant helps us inside, are trees better help outside? How far up the mountain can one go? Do I really want to run on a treadmill in the middle of a gym lined with television monitors and smelling of, well, not trees and flowers? And might there be an advantage to running instead in the mountains, to movement in nature, which Selhub and Logan call “exercise squared”?

  As we progress in our story, the lever effect is going to come increasingly into play. Remember the lever? Beverly Tatum gave it that name when she talked about sleep, that the simple act of getting more sleep made her attentive to other matters, like nutrition and exercise. One thing led to another. In the authors’ lives, this matter of contact with nature is also a lever, and one with a profound effect. A lot of this comes together at Rancho La Puerta. That’s where we met Tatum, but also the remarkable Deborah Szekely, now in her nineties, who cofounded the ranch in the 1940s. She also founded and is pressing forth with her project Wellness Warrior, to do the sort of grassroots change necessary to fundamentally rework society. The message is fitness and nutrition, but the lever that works these is contact with nature, a conscious goal of re-wilding the people, sometimes rich and famous, who are the ranch’s clients. Szekely says everything begins with the mountain at Rancho La Puerta, which is another way of saying everything begins with nature. Szekely and the ranch loom large in John Ratey’s own story, and we will get to that in time.

  THE JOYS OF ADVERSITY

  You might be thinking that nature can be capricious and cruel, and that maybe it’s better to stick to the gym. But we think this capriciousness is a part of the real benefit of living as much of your life as you can in wild settings.

  The romanticism of nature means that it conjures birds singing and warm rays of sunshine shafting through trees on a sunny afternoon—a Disney version ready to embrace us with warm, open arms. This is not nature, but, more to the point, we would not reap all of these rewards from our contact with nature if it were. And this realization brings us again to the slippery slope of evolutionary arguments that cohere too tightly to our assumptions about the crown of creation, when we think that nature somehow had us in mind through its billions of years of unfathomable motion, or that nature has our best interests at heart and will mother us. To quote the evolutionary biologist Richard Dawkins, “Nature is not cruel, only pitilessly indifferent. This is one of the hardest lessons for humans to learn. We cannot admit that things might be neither good nor evil, neither cruel nor kind but simply callous—indifferent to all suffering, lacking all purpose.”

  And this is indifference we need. Robert Sapolsky’s baboons headed us in exactly this direction when we first met them a chapter ago, with the vital and unexpected realization that predictable rewards failed to fully stimulate the brain’s circuitry of rewards, and that it was only when researchers removed the regularity that the brains lit up in happiness. Nature does not rig the game in our favor, and so it would follow that our brains and our happiness had to evolve to match an unrigged game.

  At the same time, this lack of regularity demands our awareness. Our attention makes our lives better by stimulating mindfulness. And we have seen this in action, even before the monkeys. Remember when we went for a run with our dog along a mountain path? You probably realized then and should realize now that the natural setting was in fact the key element of that activity, the major player—that and the full engagement of your brain in complex and varied motion. When we first introduced the scene, we were making a point about variability and the simple physical mechanics of motion. That is, the undulating terrain and capricious weather of a mountain run deliver the random ups and downs, obstacles and challenges to recruit a wide variety of muscles and motions. This is what the body evolved to expect and what best stimulates the brain as it coordinates the body’s physical motions. But there is not a clear line between the variabi
lity provided by nature and the larger connections we are making now. The environment randomly dealt out a set of mental challenges, some of them with real consequences, like a stumble, a broken ankle, a cliff, a snow squall, or a bear.

  Trail running is an odd sport, and we are not arguing that everybody ought to do it—but we come back to it because it illustrates some of the seminal ideas of the book. We have every reason to expect these runners to be just another bunch of jocks, with opinions and sentiments much like those of Olympic marathoners, bikers, weight lifters, or soccer players. But there are some intriguing differences in behavior that we think are relevant to our larger points. We think these differences stem in part from the natural context and evolutionary precedent of this activity.

  First, the sport is growing faster than probably any other. UltraRunning magazine reports that 63,530 runners finished ultramarathons in 2012, ultramarathons defined as any distance greater than the 26.2 miles of a marathon but almost exclusively run on trails on mountains and in deserts and forests. That number represents a 22 percent increase over the year before but a more than twentyfold increase over 1980. But further, this is not just a sport for young studs bursting with testosterone. The sport is reasonably gender-balanced, and some races are won by women. And there are big-time major event winners in their forties and active participants in their sixties and seventies, senior citizens finishing hundred-mile events. We think all of this enthusiasm stems from the fact that the sport seems to closely resemble what we did in our evolutionary past. The basic elements of mountain running appeal to those deeply seated urges encoded in us by evolution.

  All of this, it turns out, has produced an interesting internal conversation, and it is worth eavesdropping on the blogs and websites. For example, take this post from Willie McBride from the popular website for trail runners iRunFar, built, remarkably, from ideas from Erich Fromm, the German philosopher we credited at the start of the chapter with the term “biophilia.” McBride was pondering his seemingly contradictory attachment to social media on the one hand and mountain wilderness on the other:

  Our need for experiencing both the rawest nature and the most instantaneous social technologies may seem contradictory but the root cause of these peculiar rituals stems from a deep and basic desire. We want to be connected, to be a part of something bigger than our individual selves.

  In The Art of Loving, Erich Fromm writes, “The human race in its infancy still feels one with nature. The soil, the animals, the plants are still man’s world. He identifies himself with animals.… But the more the human race emerges from these primary bonds, the more it separates itself from the natural world, the more intense becomes the need to find new ways of escaping separateness.”

  Fromm further believed that this devastating departure from nature is the root cause of all human suffering: “The experience of separation arouses anxiety. It is indeed the source of all anxiety. Being separate means being cut off, without any capacity to use my human powers. Hence, to be separate means to be helpless, unable to grasp the world, things and people actively. It means that the world can invade me without my ability to react.”

  And so this idea begins with nature and our need for connection with nature, as we have argued, because of its indifference. But the flip side of this is just as interesting and is implicit in our need for connection. In a perfect world, we face nature’s indifference by connecting and drawing support from people who are not indifferent.

  8

  Tribe

  The Molecule That Binds Us to One Another

  We have been saving this story, one of our favorites, until now. It is odd that the research behind this story existed at all. It was examining a truly weird question about the safety of mothers sleeping with infants—weird because, through most of human history and in most contemporary societies, even, no one would question the safety of mothers sleeping with infants. There was, however, a particular focus of this experiment having to do with the relative positions of the two bodies being studied. Science has determined that there is a specific arrangement that does indeed optimize safety, a way for mother to curl around baby that makes the whole situation pretty bombproof, so that mother won’t roll onto baby and hurt her. This was the fear that originally prompted the research.

  Remember the example we cited early in this book about a dog having a litter of pups? The dog seemed to know all the proper steps of the process without instruction. Same deal with mothers sleeping with infants, or at least some mothers. The researchers found that mothers who were breastfeeding their infants assumed the prescribed position of maximum safety without instruction—even first-time mothers. Mothers who were not breastfeeding did not.

  The dominant hormones of childbirth and lactation are prolactin and oxytocin, and it is this latter thread we pick up now. No better place to begin than at the very beginning, each of our literal beginnings, because this is the core relationship of human society and behavior, the one that explains who we are. True enough, oxytocin figures prominently in childbirth and lactation, but it continues to exert profound influences throughout our lives.

  MOVING WITH OTHERS

  At one point in thinking about this book, it occurred to us we were missing an important piece of our story, and we realized that Eva Selhub might be able to tell us what that was. The hunch came from a personal observation. We had followed Selhub’s work and had spoken with her and her coauthor, Alan C. Logan, about their book, Your Brain on Nature, which provided a great deal of the information about biophilia in our last chapter. Beyond this, though, Selhub is a conventionally trained medical doctor who quickly moved beyond that training to study the healing power of nature, nutrition, and exercise, as well as meditation and traditional practices of healing, such as qigong. Her practice has followed many of the paths we have traced in this book, yet during our initial meeting with her, we couldn’t help but notice that she was onto something new, that personally she had hit a stride that had pumped a fresh level of physical and mental vitality into her life. We wanted to know what it was.

  And so we sat for a pleasant hour’s conversation one sunny afternoon in Boston, and Selhub began by confirming our observations that in recent months she had in fact become a “very different person.” She told us that the proximate cause of this was simple enough—deceptively so. She had joined a CrossFit gym, the regimen of physical exercise we spoke about earlier, with movements designed to provide a wide variety of challenges and ranges of motion that the human body probably encountered throughout evolutionary time. Yet this new variety of movement was not the whole story. It was certainly part of the explanation, but something else was at work, and that’s mostly what Selhub wanted to talk about during our conversation.

  Selhub admitted up front to a deep-seated loathing of gyms and the conditioned flee response to competitive athletics that’s adopted by too many kids thanks to ill-conceived physical education programs. In her telling, the real attraction in her CrossFit practice was community.

  “It feels good to have the rewards, to not only be able to excel and do something you’ve never been able to do but to compete with other people and have them be excited for you. For me, if it was just the competition, it wouldn’t work, but it’s the community. It’s the camaraderie,” she told us. “It’s really a community.… It’s kids running around, seeing parents and adults exercise and do crazy things, hugging, laughing, talking. It feels like the way it is supposed to be.”

  Feels like it is supposed to be.

  Return for a second to the record compiled by Elizabeth Marshall Thomas of her family’s experience living among the Ju/wasi people of the Kalahari Desert in the 1950s. She quotes her mother, who wrote extensively about the experience:

  The [Ju/wasi] are extremely dependent emotionally on the sense of belonging and companionship.… Separation and loneliness are unendurable to them. I believe their wanting to belong and be near is actually visible in the way families cluster together in an encampment and in
the way they sit huddled together, often touching someone, shoulder against shoulder, ankle across ankle. Security and comfort for them lie in their belonging to their group free from the threat of rejection and hostility.

  Tribalism is a cultural universal, so identified by paleoanthropologists as one of the salient characteristics that has defined humanity since the beginning. The intense bonding of Homo sapiens was likely a major factor, if not the major factor, in giving us the edge that made us the lone survivor in our line of upright bipedal apes. Literally, we can trace our bonds in our bones, but better still to trace it in oxytocin, a chemical that’s not just about nursing mothers. All women have it. So do all men. It holds us together. We’re using oxytocin here to build the case that your well-being depends on solid relationships with other people.

  THE BONDING AGENT

  Sue Carter is at sea for a few minutes trying to decide where to begin, an excusable bit of indecision. How does one begin to summarize forty years of research into the effects of a single molecule, let alone one that’s front and center at the core of human behavior (and the behavior of other species)? Evolution has been leaning on oxytocin and its close chemical relatives, especially vasopressin, to perform a variety of vital functions for a very long time, predating even humans but also predating mammals—even stretching back to the unimaginably distant and dank recesses of the evolutionary tunnel when vertebrates first split from the simpler creatures without spines. Vasopressin is an ancient chemical that likely appeared when all of life was contained in a water world, making it necessary to regulate the flow of water from inside to out of the organisms. It still does that job, even among the terrestrials, including humans.