This hidden wisdom will change how you treat your body forever | Giulia Enders: Full Interview

My name is Giulia Enders. I'm an author and physician from Germany, and I just wrote my second book, Organ Speak: What It Really Means to Listen to Our Bodies. Today on Big Think, we're going to talk about five body parts — the lung, the immune system, the skin, the muscles, and the brain — and what each of them can teach us about life.

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After I wrote my first book on the gut, I started working in a hospital and soon realized I couldn't focus on that one organ exclusively. I needed to understand how everything goes together and how different organs influence each other. In doing so, I noticed that we often have a pretty old-fashioned view of our bodies. That wouldn't be so bad if it were just a common assumption, but it sometimes really gets in the way of healing, of achieving things, of feeling good in our bodies. I wondered how we could update this view.

The lung is an organ that seems odd when viewed through societal values. In Western societies we usually think you have to be eager, push your elbows out, achieve something, put in more hours, be tough. And then there's this organ, so soft and passive, just going along with what the muscles around it do, accommodating everyone, bearing dents where other organs take up room. Yet it sits at the central part of our body, where one of our most important needs is met: breathing. Without oxygen, we're dead within minutes. So why would the body put this passive, squishy organ there—an organ that, if you poke a needle into your thorax, shrinks together like an old soap foam? The answer is that being soft, passive, and accommodating isn't necessarily a weakness, isn't something of lower quality compared to the tough parts of the body. It is perfect where it is, because without the lung being soft and accommodating, we couldn't take 20,000 breaths a day—we wouldn't have the energy. With some diseases, breathing takes too many calories precisely because the lung is no longer so soft and accommodating.

When you look around in life and society, we often devalue these softer parts—where people arrange themselves around others, try to make everything happen, keep things smooth and harmonious. But these are often fundamental, important parts of everything functioning well: in families, in workplaces, and in your own life and achievements. I learned this from the lung, and I now apply it at times.

Receiving as part of achievement

The lung's role in breathing is an undervalued part of achieving things in general. There are really three parts: the brain initiates the movement of breathing with a nervous impulse; the muscles around the lung act on that impulse and pull in air; and then the lung itself is soft and accommodating, taking the air in while doing so. When you look at what we value in achievement, everyone understands the impulse—a great start, an idea for a business—and of course we know the concept of hard work, the muscles pulling in what they want. But the whole aspect of the lung, with its entire architecture of receiving and dealing with what comes its way, is a part of achievement we sometimes don't notice. Really being able to receive what you worked so hard for and wished for in the first place—that's what the lung's architecture is all about, with all its structures and forms built just for that. I think there's much more to explore in this part of achievement.

Grandma's advice

What I didn't understand back then was advice my grandma often gave me. When I was being very eager to get something, maybe a bit tense, she would say "do mozzy"—like "soft, soft." I always took it as "relax," and when you're tensed up, that's not great advice, because you usually don't relax on command. But reading about the lungs, I realized she meant something entirely different: life can be hard and challenges tough, and if we just tense up in reaction, our energy doesn't suffice. Sometimes we need softness to go all the way.

Now, on a very stressful day, instead of clenching up, putting my muscles into attack mode, and tensing my jaw, I go really soft and relax in between meetings. I've realized this makes my energy work for me and carries me through a long, hectic day far better than tensing up. Softness is actually an important counterpart to going the extra mile and getting the things you want: softening up in between.

The Breath: Where Conscious and Subconscious Meet

There's something very unique about our breath: it can be regulated by both the conscious and the subconscious parts of our brain. No other inner organ works like this. You can't tell your kidneys to stop producing urine because you're stuck in a traffic jam, and you can't tell your bowels to stop digesting because something exciting is happening. When you're nervous, you can't just tell your heart to slow down—some monks have trained that ability, but usually it's simply not possible to command your inner organs. With the breath, suddenly we can: I want to dive, so I'll hold my breath; I'll do breathing exercises and breathe really slowly; I'll use it for singing different tones and various lengths. And when we stop paying attention, it shifts back to the subconscious mode, regulated by what the brain notices—how much oxygen we need, how much we need to exhale. This is not only an interesting feature; once you understand it better, you can really use it to your advantage.

When conscious breathing goes wrong

The funny thing about our consciousness influencing our breath is that it can often be a bit stupid and ineffective. You would think consciousness is this great thing that makes humans such an important and brilliant species—solving problems, being intelligent and rational. But when it comes to regulating the body, it's actually not much better than the subconscious; the subconscious does a better job. You often see people who focus too eagerly on their breathing, or who are stressed at work, suddenly breathing dysfunctionally: way too slow, way too fast, way too deep, or tensing up their muscles to breathe just from the chest because they're stressed. None of this is effective. It takes up a lot of energy and can leave people feeling more nervous than they need to be, dizzy, or with neck pain or a headache in the afternoon—or really tired by early afternoon because of all that wasted energy. That's the negative side of breathing with your consciousness.

When conscious breathing helps

Luckily, there's also a positive side, and it usually applies when the subconscious isn't doing so well—when it's scared by something, worn down by stress, becoming emotional and worried, or waking you up at night because something is bothering it. Then your conscious mind can, for once, take care of the subconscious and deliberately slow the breathing down so the heart can relax. The heart tends to get hectic when it has to pump freshly oxygenated blood around all the time; when you breathe slower, it shifts into a more chilled mode. The nerves around the heart notice, the nerves in the brain notice, and this drives down stress hormones in the blood and the heart rate. If you really know how to get in the groove and cooperate well, this can sometimes help with anxiety.

Then there are times when you're really tired and want to wake your brain and nervous system up a little, and you use the opposite technique: breathing really fast. Some call it the espresso technique. So those are the two directions—advantage or disadvantage, more awake or more relaxed—and if you know how to play with it, it can come in quite handy.

Dysfunctional breathing and how to fix it

The breathing center in our brain gets information from many different areas, including conscious ones that can stress it out. Then we breathe unnecessarily fast and deep, which is called dysfunctional breathing. About 10% of people—probably a little more—breathe this way, for example in a stressful job. It takes a toll and can make an already stressful job even more stressful. So it's worth checking your inner stress and workload, because that part you can easily fix.

The solution to this type of dysfunctional breathing is learning to let the subconscious take over again, since it does a better job, and to stop annoying your breathing center with constant stress. You may have come across one or two such techniques, because this is one aspect of meditation: people say just sit down and observe your breath—and it's quite hard to simply observe it without consciously regulating it. But that's exactly what you should do in those moments, and it's something you can learn.

Another technique is to really stop your breath after exhaling and wait for the urge to breathe in again, so that exhaling doesn't become a reflex where you instantly have to breathe back in—which sometimes drives up the breathing tempo unnecessarily. Waiting until you feel the urge to breathe back in is also a technique advised to people with asthma, who can develop these dysfunctional patterns; sometimes it worsens their condition without the disease itself doing so. These are just two ways you can chime in, regulate a little, and see where that takes you.

In such a short time compared to the rest of human history, the body also takes a sprint. Something that happens in both situations is that we accumulate waste products while sprinting. In the body, we accumulate CO2, because that's the side product the muscles produce when we're really moving and doing a lot of work. And in the world, we saw exactly the same thing: we created all this CO2 and waste from doing so much in a really short time.

So what's the solution? What does the body do? It actually uses more energy and has to put in an effort to get rid of the additional CO2. Suddenly, exhaling costs the body energy, which it usually doesn't. When we sit around relaxed, exhaling takes no energy—the elastic fibers just go back on their own. But during a sprint, the body needs extra energy to push the air out.

The fascinating parallel is that this takes about 5% of our energy resources. Similarly, when it comes to climate change and the pollution we produce while progressing as a society, well-renowned research teams say it would cost about 5% of GDP to get rid of these wastes in a responsible and smart way. So we can look to the body and ask: why shouldn't we do it the way the body does? It doesn't seem like such a bad idea.

当我们谈论免疫系统时，我们经常使用与战争、战斗和杀戮相关的词汇。虽然这是免疫的一个方面，也是一个重要的方面，但这并非全部，有时也相当不准确。所以我想在这里引入一个不同的视角，你可以选择是否采用，但这个视角在我成长过程中对我产生了深远的影响。那是我祖母最好的朋友，一位来自美国的钢琴家。他来到德国，在森林深处有一栋房子。每个周末，各种各样的人都会聚集在那里。现在回想起来，我觉得那非常特别，因为小时候你只是把它当作理所当然。但每个人在那里都感到如此安全，非常不同的人都感到安全。有一位来自城市的严厉律师，一位有着复杂家庭背景的伊朗女性，一位充满色彩的剧院导演——所有这些截然不同的人聚在一起，感觉良好、安全、自在。后来我意识到，Bill 与免疫系统共享着另一种安全元素，那就是真正地、不带评判地了解他人，对他们充满好奇。

我们的免疫系统做着绝对类似的事情：它每一秒都在巡视我们的细胞——当我坐在这里时它也在这样做——并询问“你最近怎么样？这里发生了什么？那边情况如何？”以便真正确保安全以明智的方式实现。例如，如果病毒存在于视神经中，它不会攻击视神经，因为我们可能会失明；但如果病毒在喉咙细胞中，它就会攻击，因为它可以替换这个细胞。它很聪明，但这只是因为它真正了解我们体内的细胞。Bill 也做了同样的事情。

此外，对于某些人，Bill 只是出色地容忍了他们。也许他并不太喜欢他们，但这无关紧要。为什么要浪费能量去引发不必要的炎症呢？我们的免疫系统也必须这样做来保持我们的安全。不必要的炎症，如过敏或自身免疫性疾病，不仅浪费能量资源，而且很危险。最后一部分是真正与有益微生物良好且友好地合作，Bill 当然也出色地做到了这一点，拥有所有这些美好的朋友。我们的免疫系统对我们的肠道微生物以及皮肤等各处的微生物做着同样的事情，与它们合作以真正保持我们的安全，因为正是这些微生物产生微小的抗菌肽或其他物质，并从我们的食物中提供维生素。如果它不这样做，就不会有安全。因此，攻击和战争隐喻并不是通往安全的唯一途径。Bill 和免疫系统给了我这样的洞察。

细菌的真实图景

关于微生物，我们经常有一个非常错误的认知：大多数时候，它们绝对不是危险、有害或具有威胁性的。地球上有数万亿细菌，但已知病原体只有约 1,400 种。这是一个极小的比例。如果与人类相比，就好像这个星球上只有六个人是恶劣和刻薄的，而其余的人都相当不错。我认为这能让你更好地了解细菌的真实比例，即它们并非总是坏的。事实上，它们的主要任务是在动物和我们人类之间传递基因，帮助我们消化，或者通过占据空间来保护我们免受其他不该出现在我们体表的细菌侵害。我认为这才是关于细菌的完整图景。

病原体如何变得有害

当你观察那些能够使我们生病的细菌时，有一些因素有时与人类生活或心理学中不太有益的因素相似。其中一个例子是偷窃——偷窃对宿主很重要的东西。所以微生物在这里就像遵循某种罗宾汉原则。如果你从宿主、从人体中拿走身体不一定需要的东西，那没关系——那不是坏微生物。有些细菌会拿走我们的一些食物，从中产生某些东西，我们甚至不介意，也许还对我们有益。但其他细菌会拿走营养物质，例如铁，而铁非常稀缺且难以从食物中获取。通常这样做的是病原体，这导致了一个有趣的现象：当我们感染时，我们的免疫系统会巧妙地将所有的铁从血液中取出，藏在某个隐蔽的地方，然后等到我们康复后再将铁释放回血液。因此，感染后不久你去验血时，铁含量可能会降低，但这不一定是坏事，因为它可能会在第二天内恢复。

细菌对我们有害的其他方面包括越界——不尊重某人划定的界线并说“不，这是我的喉咙，你不能入侵这里”。坏微生物会无视这一限制。好微生物会说：“哦，显然那里有一堵墙，有一道喉咙壁，我们不会入侵。我们就待在粘膜上，在这里生活得很好，这样大家都能和睦相处。”但坏微生物有时会无视这一点，甚至越过边界进入我们的细胞。这通常是一个坏迹象——不尊重别人说“到此为止，不能再进一步”。

另一个例子几乎可以说是一种“煤气灯效应”，被称为免疫入侵。当我们的细菌注意到我们的免疫系统……

When our immune system is not okay with bacteria doing something to us, they have a choice. They can either become a little nicer, shutting off some genes that are irritating us, or they can try to go around the immune system's reaction — and bad bacteria opt for the latter, in a very mild way. Sometimes this doesn't have to be horrible; it can just mean they make our immune system more tolerant, which is still okay. Some of them might even protect us from unnecessary allergies. But if they go further and really fake it — masking themselves, pretending they're not there while the immune system is looking for a problem — they use proteins from our blood to cover themselves and seem like maybe it's our own cells doing the harm to our body. This is the case of immune invasion, and it's a sign that they're tricking us: they're not reacting to our upset, they're just hiding from it. This is usually bacteria causing some pretty dangerous infections.

Then there are also toxins — little things bacteria produce that fool our own regulation mechanisms. For example, toxin-producing bacteria that cause diarrhea go in between our gut cells, where they can initiate diarrhea: the cells spread a little bit and let all the liquids through. They're using something our body actually does to protect us, but to their own advantage and completely unregulated. This causes horrible diarrhea with ounces and ounces of liquid coming out, compared to normal diarrhea where after a day or so and a few trips to the toilet, you're okay. Manipulating others into thinking they're doing the right thing when it's really to their disadvantage is something very bad. Toxin-producing bacteria are often the ones we have to vaccinate against, or have some preliminary medicine or caution for, because they can cause quite heavy infections.

Bacteria turn bad because of us

Some bacteria turn into bad bacteria because of us — because of something we're doing. This is a rather new finding, too, because we now have great ways to analyze bacteria sitting on all kinds of surfaces of the human host. We see that quite a few people carry throat-soreness bacteria, diarrheal bacteria, or other bacteria that aren't supposed to be good — but they're not doing anything, just hanging around. We now understand a bit better that when bacteria are part of a good community and aren't being attacked by immune cells or stress reactions in our body, they won't unpack all of their properties and disease-causing factors; they just go with the flow and become a milder version of themselves.

The same shows up in pandemics: chopping down trees in a forest so that animals move into city areas carrying bacteria or viruses that aren't necessarily bad for them but are for us, or just leaving egg salad standing around too long at a party so it accumulates a few more salmonella after a while. What we do to others — to microbes — can cause them to become more evil or disadvantageous to us. So we are a factor as well.

The immune system's more differentiated view of "bad"

The way the immune system judges whether things are bad or good sometimes gives you a fresher perspective on what bad is. We tend to put things in boxes: this is bad, stupid, we look down on it, it's of negative quality overall — and then there are the good things we aspire to be. But for an immune system, it has to be more differentiated; it's not as simple as saying something is just bad. Looking at the history of humans trying to figure out which bacteria are bad, they made some very dull, simple mistakes in the beginning and got better at evaluating these things by learning from the immune system. Initially, for example, humans said all bacteria are bad because they found them in diseases — bacteria cause tuberculosis, so bacteria in general must be horrible. There was even a time when surgeons would cut out a whole large intestine because they found bacteria in it and people had some troubles with them. That was, of course, horrible.

From Killing Bacteria to Understanding Them

Many people died back then because of that. We got a bit more differentiated and said maybe it's certain species of bacteria being bad. You could almost say this relates to racial theory, saying this species is bad or that — and those are very stupid mistakes, because it's not that simple. In every species there are bacteria doing great things and bacteria doing a bit of trouble.

As science got better and more nuanced, we saw that even within the same kind — take E. coli bacteria — they can be genetically almost identical, but one is just an E. coli hanging around in the gut, while the other causes a disease like a very severe, bloody intestinal infection that is very dangerous to your life. So we really had to turn to the immune system and to science and realize it's not about the boxes you want to put things in, but about looking in detail at the interaction: are bacteria going around your immune system to avoid it? Are they stealing something from you that you need? You can even go further and ask what our own take in it is — what did we do to these microbes to make them sometimes react that way? Sometimes these are just survival strategies: a sore-throat-causing bacterium doesn't want to harm anyone; it's just trying to find a new place to live.

With very new approaches to antimicrobial therapies, we're not even planning on killing them all with antibiotics anymore — we're trying to be smarter. We might just block one protein that's doing us harm, or by doing that, maybe even teach the bacteria to select the ones that aren't doing the disadvantageous thing and become a bit nicer on the way. It's really about making this interaction smoother, smarter, more diplomatic, so that quite a lot of bacteria might stop harming us and instead become like some colleagues sitting around doing nothing — just by getting to know and understand them much better.

I think that can be a lesson for the bad things in life as well: don't just shoot them or push them away, but really understand and look into the final reasons why — that can sometimes give you a good way out. And sometimes it can also show you there's no good way, so you really have to avoid those. But not always — and those cases are the interesting ones.

Rethinking Autoimmune Disease

When people are diagnosed with an autoimmune disease, what they often hear in the doctor's office is: "Your immune cells are attacking your own body." I really don't like that sentence, and I also think it's scientifically no longer accurate. What we know now, looking at research from the '90s like the danger hypothesis, is that the immune system is not just stupidly aggressive. All the cells in our immune system have one goal: to keep us safe. Sometimes they go a bit too far with it — you could say almost like overprotective parents who want to be very sure nothing horrible is happening, so they just do a bit too much, and that can be a bad thing. Of course, these diseases are to be taken seriously, they're not fun, and it's not good that the immune system makes a mistake like that. But it's really not because it's aggressively turning against us.

Understanding that can shift your perspective on how to deal with and treat the condition. For example, we now have additional therapies and options besides medications: stress relief techniques, watching your diet closely, meditation, aromatherapy, and similar things. That's not just "do some good things" — making your body feel better also sends a little notice to your immune cells: "I'm doing better, you can maybe tone it down a little bit." Taking medications for decades of your life also feels very different when you say "I'm swallowing this to fight back this stupid autoimmunity" compared to "I'm taking this to calm you down — you don't have to go so hard, I'm okay." These things do matter, and I've seen in hospital how my patients reacted when I could explain it differently.

One example was a formative moment for me in understanding that this was an important way of explaining things. Early in my medical career, I had a patient diagnosed with a chronic inflammatory bowel disease. She had been in our hospital a few years earlier with a very severe intestinal infection, and she was understandably downbeat about receiving this diagnosis. I went to her room later that day and said: your gut really witnessed this horrible infection, and I know it seems like double trouble to now also be diagnosed with this disease. But it's also because your immune system had this very dangerous thing happen and had to learn that it should have reacted a little earlier, could have done more, could have been a bit more careful — and now it's just following through with that lesson. In diseases like chronic inflammatory bowel disease, the immune system may go against things like very harmless gut bacteria, initiating inflammation right away. It is a mistake, but not because it's aggressive and stupid — it's really because it witnessed something horrible and now tries to protect you at all costs, going a bit too far. Just understanding it this way helped my patient and gave her a milder attitude toward the disease. I hope this does something.

What Safety Really Means

One lesson the immune system taught me that sticks with me to this day is that safety doesn't mean having no risks at all and pushing all the bad far away from you. Safety really also means coming up with solutions, being flexible, finding ways. Our immune system does exactly that: by having memory cells, by reacting toward germs flexibly — whether they are in a wound somewhere, in the optical nerve, or in the gut — it has all these ways of finding solutions instead of only attacking things or keeping risky things away. Thinking of safety like this has given me a bit less anxiousness about safety in my own life. I know that when I know myself and look out for different ways of solving something, I'm well off — compared to just trying to keep everything risky far away.

I've noticed with my patients, and personally, that in everyday situations we often feel we shouldn't feel the way we do. For example, when my grandma died, I wasn't the grieving widow in the black dress crying into her soup — I was just numb. The same happens with a promotion you don't feel excited about, or the birth of your first child when you're not immediately overwhelmed with love. People ask, "What's wrong with me? Am I broken? Am I weird?" No, you're absolutely not. Humans are more complex than Hollywood movies or social media threads telling you how you should feel. The human body is complex, and that complexity can actually be a helpful rail to hold on to while you figure out what's happening.

For me, when I was numb and missing the typical emotions, it clicked when I read about wounds: this is the process I'm going through. It's like tissue being ripped from your skin, and then a crust covers it within seconds — a numb crust, just like how I was feeling. A few days later you look at it and nothing seems to be happening; it looks the same as two days ago. But an illustration in a medical book showed everything happening underneath: reorganization, attracting cells that help fix the injury, building new structures to patch things up. In that moment I felt at ease again and was finally able to cry, because I realized I had to do all this reorganization with the person I loved so much. Maybe it isn't conscious all the time, maybe it doesn't hurt right away, maybe it's covered up — but it's happening, and it's okay to let it. I even noticed similar signs, like suddenly wanting to take a walk again or eat something specific, just as a wound attracts the cells and factors it needs to heal. I think many other processes in the body can work this way for people feeling like this.

The healing power of touch

The fascinating thing about human touch is that it can have effects quite similar to medication. We often assume certain benefits require a pharmacy, money, and a pill — but we're human beings, and not everything has to come in a pill package. We thrive on touch. We see this in intensive care patients, and even in people who don't like touch much, such as some people with autism or ADHD who find it overstimulating: when touched by someone they feel is okay, it still benefits their body and nervous system.

This research area opened up with studies on pre-term babies, where skin contact after birth lowered their stress hormones and improved their metabolism. Even a year later, children who had good skin contact were less stressed and more flexible in their reactions than babies who didn't. Being touched is fundamental for humans, especially in phenomena like loneliness. Widows, for example, would be well advised to get a massage now and then — just to have some touch if they're deprived of it — and to remember it's not only medication that can calm you down.

Interpersonal synchronization

A good example of touch in everyday life is interpersonal synchronization. In an experiment that has since been replicated, one person lies in a tube while a partner they feel close to sits outside holding their hand. They can't see each other, but their heart rates synchronize, skin conductivity — a sign of stress activation — drops, and blood pressure and stress hormones come down to the level of the more relaxed person. Through skin contact alone, you can transmit a calm nervous system to the other person — and not the other way around, which is a good thing. Now that we know this, we might use it.

Loneliness, Wound Healing, and the Skin

When you look at loneliness, there is of course the typical kind—not having other people around you, not feeling close or connected. But I think there is another kind, which I would call self-loneliness. Studies have looked at how you touch yourself, how you talk to yourself, how you handle and take care of yourself, and there are very different ways of doing this. We rarely talk about it because we don't think much about having an inner world and a relationship with it, not just an outer world. We're so focused on the outer world, with all the noise, news, and messages constantly coming at us, that we forget the inner world also shapes how we go about life and how we feel.

People touch their face when they get nervous, as if to say "hello, I'm still here"—you can see this in brain signals indicating the face is there. Then there's showering: do you scrub yourself like a farm animal, fast and effective, or are you gentle and careful with yourself? Those questions translate directly to how you talk to yourself. Are you talking down on your body, or being friendly with it? Medically speaking, we have indicators that you can become so removed and hostile toward yourself that you become self-lonely rather than self-friendly—on all levels: touch, thought, and action.

Two ways wounds heal

Genetically, humans can heal wounds in two different ways. The one we generally know ends with a little scar. The scar forms because immune cells try to keep everything safe while something vulnerable, even damaged, is being healed. They produce various substances, sometimes aggressive ones, to fend off intruders like bacteria. That makes sense as a step of caution. But in the womb, as embryos, we don't heal that way—we simply pull what's left and right together with a kind of tissue string, and this causes no scars. We can get closer to that by taking good care of wounds: keeping them really clean and putting a water-resistant bandage over them. It's called wet wound healing in medicine. The immune system gets more safety this way, can use different techniques, and scarring is often less.

Scars as a metaphor for psychological healing

When a wound heals, one step is forming a scar, and this process has striking similarities to psychological healing after being hurt. Wounds don't all heal the same way. Some overreact after a hurtful incident—like someone who was burgled putting five locks on their door, or someone who was cheated on constantly checking their partner's phone. A bit too much can happen with wounds too: it's called hypertrophic scarring, when more tissue works its way up than necessary. This can even go completely out of hand in keloid scars, which won't stop growing new tissue unless a professional intervenes with certain techniques.

The opposite is also possible: hypotrophic scars, which sink below the level of the surrounding skin. What happens here is similar to people after a tragic loss who keep replaying things in their head, being hard on themselves: "What could I have done differently? Was it all my fault?" Our immune cells can do exactly that—after an incident, they go to the wound and keep attacking the structures that are just trying to rebuild everyday life, so the scar sinks below skin level. Older vaccination scars on the arm or acne scars can look like this.

This parallel can be helpful when you're going through a troubling time, experiencing something hurtful or a loss. You might ask: am I going in the hypertrophic scar direction, being too tough on myself? Or the hypotrophic direction? What a scar actually needs to heal nicely and without disruption is a patch over it to calm it down—fewer outside influences, cells doing their thing without too much disturbance or stress on the skin, just good nutrients and calm to get through it.

Death as the coat of life

When you look at a human, you basically see skin, and the outermost layer of it is dead—just dead cells. It seems ironic, or maybe just genius, that death is the coat of life. For the skin it makes a lot of sense: these dead cells aren't sensitive like the ones underneath, so robust scratching, moving, and touching isn't so bad. They also can't be infected by viruses, because viruses need living cells to live, replicate, and thrive in—to a virus, these dead cells look just like a chair or the floor. It's a great invisibility cloak against the viral world. The only viruses known to infect skin are wart viruses, and even they can never do it with intact skin; they always need a little tear to get under the first dead layer to the living cells. The uppermost layer also can't really bleed—if you cut just a few micrometers deep, there's no blood; cut deeper and it bleeds, and at a certain level you reach tiny dots of blood vessels.

All in all, this creates an atmosphere of protection around the living cells. And in a way, couldn't you say that's what happens during life? We need death, we need this limit, this contrast, to really value, appreciate, and protect aliveness. Certainly in a body, it works that way.

The image we have of strength—of achieving things and getting stuff done—is still very old-fashioned, and so is the way we think about our muscles. We picture the Popeye figure: someone pumping their biceps, lifting a big weight, and then doing the thing. And since men have more muscle mass, the assumption follows that men are stronger and therefore get things done. But when you look at how muscles actually work, there's a different angle on strength and achievement—it's not only about moving things.

I chose my mother as the opening image for this chapter because she embodies that for me. She achieved great things that society might not recognize as such, but that were very strong and powerful to me. She raised her children as a single mother, always going at 150%. Sometimes I'd see her asleep on the couch in the evening because the day had been so stressful. As a child I just thought she looked peaceful; now I understand how hard all that work really was. Like her, strength doesn't always mean lifting something heavy or having a visible career everyone can point to. Sometimes it's simply having a certain attitude—which takes a lot of strength.

Muscles work the same way. We don't only have concentric force, which moves things; we also have force that holds your spine upright, and forces of resistance—when something heavy pushes against the direction you want to move, your muscles can use strength to stop it, or to slow it down. If you hold something heavy and lower it slowly instead of letting it hammer to the floor, that's strength too.

Different muscles express strength in very different ways. One of the strongest muscles in the body is actually the one used for chewing, because it works at a perfect angle. The muscles of your eyes excel at extremely fast changes of direction—also a form of strength. We have muscles in the bladder that we hardly ever think about—you wouldn't brag about your strong bladder—but they triumph by using tiny amounts of energy to get their work done, perhaps slowly, but extremely resourcefully. Strength is built into the body in all these different forms, yet in work life and society we often see only the Popeye version. Our muscles remind us there are many other ways strength can show up—and so did my mother.

There are great benefits to physical exercise—brain health, metabolic health, reducing the risk of many diseases. But the wonderful effects don't happen while you exercise. They happen during the downtime, afterwards, when you lie down, do nothing, and regenerate. Maybe that can teach us a lesson: great things come not only from action, but also from the time we give ourselves afterwards to reflect and consider what might be done better next time. In the body, this is when the heart muscle builds more capacity, the lungs become stronger, and the muscles replenish their stores—perhaps even adding a little extra reserve for whatever challenges the next day might bring.

Our brain reacts so sensitively to sports and exercise that sometimes you might think, "My muscles aren't growing, but I've been in the gym all week." If you could only see your brain then, it has all these new receptors really reacting towards what was demanded from it to get the movement done.

Working and getting things done is often compared to achieving something in exercise and sport — going the extra mile, carrying the load, all these words we use. But while we do so, we lose sight of the fact that the beneficial things from exercise happen in the regenerative phases afterwards, the downtime when you lay down. I don't think we see that so often in work, but it's quite similar. Medical research shows this too: you need different kinds of little breaks during your day. You can have just a few seconds to sigh, a minute or so to have a coffee or talk to a colleague, an hour for lunch, your evening time after work, and a weekend to really replenish.

We don't take these things seriously; we just see them as charging the battery to get stuff done afterwards. But if you follow the muscular comparison through, these are sometimes the more important phases. This is when your body reflects and asks, "How much resources do I need here? Should I strengthen the heart muscle and the lungs? Should I change my brain chemistry a little bit to get things done better?" All the beneficial effects we praise about exercise really come from that time. Professional athletes plan their training schedule not by what they get done actively, but by how long it takes them to recover — only then do they go again and do more.

In work, this could be quite helpful for things like burnout syndrome, when people stop looking at breaks because they think they're unimportant and they should just get more stuff done. That actually makes them get less done, just as in training: when you overtrain for weeks, you can even lift less weight, because your muscles didn't have time to use regeneration to get stronger. This teaches us that we're not machines you plug in so all the great things happen. We're beings that adapt, that ingeniously evolve and shape ourselves — and we do so during downtimes.

There's also the aspect of over-relaxation, which is equally to be taken seriously. People know this phenomenon: if you don't exercise, you lose muscle, and if you have to lie sick in bed for a while, you can lose dangerously large amounts of it. We also know this from everyday life — when people retire, they are scared of that time, scared they'll get less and less done, and sometimes that is the case when you don't challenge yourself. So just as there is burnout and overtraining, there is over-relaxation too, which is dangerous for people who lose employment or lack a task right away. Both extremes exist in the muscle, and both can be tackled similarly to muscle work.

Titan: why output isn't just input

A few years ago, science discovered a protein called Titan. It solves a long-standing riddle: isn't success, unlike muscle workout, just based on how much work we put in? Don't we get exactly out what we eagerly put in? Titan explains why the answer is no, because there are dynamics. Life is dynamic — influences and forces come your way, inhibiting you and standing in your way, and you have to work around them. Our body knows this, and for that it has this protein, which is a little like a spiral, like an old telephone cable. It can take up energy that is coming your way and blocking the movement you want to do, works together with it, and then, when you have a chance to move your way again, it unloads that energy and gives you an extra spring in the step, so to say.

We didn't understand why this happens until we discovered Titan, but we now understand phenomena like why Olympic sprinters jump before they run: that's how you charge your Titan and put energy on it. Or why exercises like yoga and Pilates make athletes who are already really strong even stronger — those are exactly the types of movements that strengthen, modify and fine-tune your Titan springs and your muscles. The same applies to work life and success: it's not only about how much work, time and eagerness you put in. It's about understanding dynamics and really cooperating with them.

Exercise, Energy, and Strength

When I got deeper into sports research, I discovered theories and researchers that made exercise grow on me. One of them was Hammond Pona and his work on very traditional people living close to nature—roaming, collecting plants, hunting, and moving constantly. He showed that they only need 2,000 calories a day, just like we need when we sit at the computer all day. So exercise is really just distributing your energy differently.

If your body notices after a while—usually the first six months you might really lose weight because you're using all this energy to move around—but then your body smartly adapts and distributes it differently. You might produce a little less sex hormones, a little fewer immune cells, and store a little less energy in your depots. By saving that energy, it makes possible all the movement you're now doing all the time. This shows that sports and exercise is not about taking calories off; it's about making your metabolism more efficient and resourceful. And that's a nice effect, because having less sex hormones, fewer immune cells, and less storage reduces your risk of some typical modern diseases—cancers associated with sex hormones like breast and testicular cancer, metabolic diseases, and obesity when you have less storage stuffed everywhere. That is one way sport produces these beneficial effects.

Exercise as a playful game of stress

There are also other effects of sports that I wasn't so aware of but now really appreciate. To people who find exercise miserable, I would say you're absolutely right. Exercise is miserable; it is so similar to a disease. Your temperature rises, your heartbeat goes up, your blood pressure really has to deliver, it is stressful—you even have stress hormones in your blood. But that's also the intriguing thing about it. If we don't take it so seriously all the time, and if we can tune out those voices telling us that being unhealthy—or your mental health, or how you look—is your fault when you don't exercise... I really don't appreciate that pressure. What exercise can be is a playfulness, a playful game of stress: stress that isn't really dangerous to you, where you can stop anytime you want, where you can even get a giggle out of something, or just enjoy moving your body—brain and muscles coming together, doing their thing, sort of friendly. Not having to make sense for work, not carrying responsibilities, just moving and feeling.

A playful game with stress is actually quite a good idea, because it can teach your body that a rise in temperature is not so horrible, that it can come down to a relaxed state quite quickly, that using up energy molecules or breathing quickly isn't so threatening, and that vibrations all over your body can strengthen the bones, for example. I think this perspective can bring back an aspect of sports that it has often had in other cultures throughout history—one that is more enjoyable than the perspective we have now.

Strength as converting energy

One key thing to understand about strength when you look at a body is that it is much more than just moving one thing forward or lifting something heavy. Where does strength even come from? It's an interesting question. It is not our own strength that we possess and then use; it is really a way of converting energy. If you want the big picture: this is energy produced in the Big Bang, now guided through all these different systems, and humans and living beings managed to guide this energy into movement.

And movement can be very different. It can be lifting something heavy, but it can also be standing very stiff and still, holding a certain posture and attitude. It can be working against forces that don't go your way—resistance, so to say. It can be eyes moving really slowly or really fast, a heart pumping 24 hours without a break, a bladder or large intestine being absolutely resourceful, or muscles like the legs or arms wasting a huge amount of energy very quickly just to get ahead. These are all different kinds of strength, all using energy in different ways—like people in the workplace or people in the family. Very different strengths, very different ways of using energy. And the body uses them at just the perfect places sometimes. So it's not about who's the strongest at lifting a weight, but who's in the perfect place. A bladder is in the perfect place; a biceps should never be there. Those are one or two things you can learn about strength from the body.

In chapter five, on the brain, the argument is that we are more than machines.

When writing about the brain, the author often thought of her sister, because the two of them are a team where each has strengths the other lacks. The brain works the same way. We tend to rank these abilities: being awake is valued far more than being asleep, softness and emotion are talked down compared to rationality and clear conscious thinking, and addiction and motivation are treated as one horrible and one great. We also separate the brain from the rest of the body, imagining it as the chef up here telling the stupid flesh mountain underneath what to do. But the brain is really about relationship — about connecting very different abilities and strengths to get the best out of them, and it is never the case that one is worse or less important than the other. You need sleep to be awake, and you need to be awake to have a good sleep, and the same goes for all these other areas.

With artificial intelligence now seemingly everywhere, we go overboard a little by making it out to be a genius thing, smarter than humans can ever be, soon leaving everyone unemployed. While there is definitely truth, danger and importance in that, we should also check the numbers and quality. The researcher I admire, Iruna Cohen, compares the immune system and AI because both create networks: immune cells communicate with each other, deliver information and connect it into patterns like an immune reaction or an allergy, and AI does the same. But AI uses about 150 million data connection points to create an answer and pattern, while something organic like the immune system has two to three trillion cells connecting information — far more than any AI we have at the moment, so it is way more complex. Cohen says the immune system is more comparable to human consciousness, whose nerves and information connections go far above that number and are genius in that way, creating consciousness out of thoughts, feelings and patterns.

When you think of the human brain, the processes AI can emulate are about 10 to 15% of what a brain is doing. All the rest is the phenomenon of being alive — feeling, having taste and smell, connecting it all to experiences. By being so fascinated by machines, computers, phones and AI, we ignore that we are so much more than this. We can emulate a small part of it, call it AI, and work it with great amounts of data, which is wonderful, but we will never have something that is alive, conscious and experiencing.

So I want to take a bit of the glamour away, because it also means we are not stupid, broken, incapable or less than machines. It means we are genius beings, and we should have a feeling for that. We live in a time where the outside world has become really noisy and loud, dictating too much how we see ourselves and how we think we should feel about our bodies and our lives. So let me put a counterweight, which necessarily has to do with money — let's weigh it up and look at the numbers.

If you tried to rebuild a body using human cells, getting them into all the right shapes, tiny blood vessels and delicate nerve fibers, you could easily end up at a sum of about 11 trillion, and the brain alone is one trillion of that. That value is like the ten most valuable companies on the stock market right now, or all the buildings in New York City, or all the buildings in London — or, to put it more finely, all the artwork known to be on the market to sell. What does that tell us? There is the value of the outer world, all these things that scream at us to be or not to be, but there is also the value of this living, earthy world that has been there for millions of years and has perfected its ways, and that we are luckily part of.

Sometimes I see patients in the hospital, really sick or even at the end of their lives, realizing they have had this valuable, wonderful body — sometimes making mistakes, but keeping them alive through this delicate, ingenious thing — and that it will soon be gone. They realize its value all of a sudden, and how they ignored it or never tried to understand it or cooperate with it more lovingly. Seeing this is very touching, and I am grateful to have witnessed it earlier in my own life. I want other people to feel and notice this, and to incorporate it earlier in their lives as well.

We are so caught up in the cognitive world — sometimes we are our phone, we are a screen the whole time, and we lose track of reality, of the touch of reality, which can be quite funky and even dangerous in a body. People who spend more time detached from their physical sensations, just living in their thoughts, have a higher risk of anxiety, depression, feeling irritated, and even some mental diseases — that is a sign of it. And I wonder...

Sometimes I wonder whether this is happening to us as a society as well. Do we detach too much from the realness of life—from what we actually need to be alive and well, to have good relationships, to feel safe? I feel like the body can re-anchor us and bring us back to the reality of life at times. A brain learning more about its organs, really understanding their genius and strength, and then knowing how to deliver to them, cater to them, and work with them better than before is very valuable—and in more aspects of everyday life than you would think.

Learning about our organs, about our inner life, teaches us sometimes not to look down on the body as much, or to see it merely as something that has to function and be optimized, but really as something full of wisdom. There's a lot of lost wisdom in it, like seeing the intelligence of softness or accommodation—not treating safety as just a military operation, but as smart ways of cooperation, tolerance, diplomacy, and curiosity. You could even define strength a bit more modernly; when you look at modern research on muscles, that's simply possible.

Taking the intelligence of the body and its systems—all these fascinating structures that existed long before our man-made systems and value systems came along—is, I think, a very grounding force and a friendly one, and quite frankly a very polite and lovely sort of power.

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