Science YouTuber Philipp Dettmer: ‘Getting cancer was super-interesting’
Skim Philipp Dettmer’s CV and you’d have to say he was an improbable candidate to become one of the world’s foremost science communicators. The 35-year-old from Munich dropped out of high school in Germany aged 15. He eventually did a history degree, and only became involved in science through his interest in infographics. This led, in 2013, to him creating Kurzgesagt (AKA “In a nutshell”), one of the most popular science channels on YouTube. The platform’s irreverent, kaleidoscopic videos – stripped-back guides to everything from black holes to Covid – have more than 15 million subscribers and have clocked up almost 1.5bn views.
Dettmer has now written a book about the human immune system, which has intrigued him for more than a decade. Everyone has an opinion on theirs – whether it’s good or not up to much; how best to “boost” it – but it can be a struggle to understand how it works. In Immune:A Journey into the Mysterious SystemThat Keeps You Alive, Dettmer uses eye-catching graphics and simple language to untangle the strange, compelling, sometimes grisly methods our bodies use to defend us from disease.
Would you agree that you’re an unlikely science communicator?Yeah, totally. It’s all fine and good now, but I was really, really bad at school. I was utterly uninterested and I didn’t know anything. I was just doing drugs and playing video games – that was my thing.
What changed?My poor parents sent me to a school outside the system, where people like me are put by worried parents to get any sort of degree. And there I had one teacher, an older lady, probably in her 60s, and my God I was afraid of her. I was 17 and ready to be a disturbance to everybody, and her method of teaching was basically to scream at you. She was teaching history, but she made stuff so interesting! And I distinctly remember sitting in her class being screamed at by her, and it hitting me: “Wow, this is so cool!”
And how did that lead to Kurzgesagt?It was like: “Hey, if you present stuff differently, it becomes fascinating!” And I hope with Kurzgesagt that I can create these moments for as many people as possible, this spark moment. So to answer your original question: I’m a very unlikely science communicator. I have no business doing that at all.
You reach millions of people on the YouTube channel. Why write a book? Books have lots of downsides: they are big and long, and you need time to focus on them. But a big misunderstanding some people have is that you learn on the YouTube channel. If you’re watching science videos, maybe you learn an aspect or you understand the concept better, but you will never fully understand a subject from watching videos. A book does something different to your brain. If you read the book, you hopefully will have a different concept about yourself and your body, and what being sick means. And I don’t think our videos can do quite the same for you.
Do you have topics on Kurzgesagt that you know will be surefire hits?
For sure. Black hole videos will always work. Nuclear weapon videos always work. We certainly make a lot of stupid videos, but there needs to be a balance between stupid videos and the less stupid ones.
You note that only the brain is more complex than the immune system. How much of a challenge was it to make the subject accessible?I’ve researched many different topics, and none is even close to being as hard as immunology. A few months ago, I had to read an immunology paper for a video, and it hit me again: I can read this now, but I’m reading at the speed of a first-grader. And I’ve written a book on this topic!
You had cancer at 32. How did that inform your interest in immunology? It definitely strengthened it, because cancer is an immune-system failure, in a sense. It’s weird to say, but it was genuinely one of the most interesting experiences of my life. So, for example, the chemotherapy was working too well at some point and I basically didn’t have an immune system at all. Then I got some special drugs and my immune system bounced back so hard that I could have got cancer again. It was genuinely super-interesting.
You note early on in the book that during the short time we’ve been reading, our immune system will probably have identified and destroyed a cancer cell in our body. It’s an extraordinary aspect of our biology, isn’t it?Yeah, and what’s so fascinating about it is that it’s doing its job constantly. And when it fails, you notice fairly quickly. It’s not an external entity doing something for you. It is you! All your little macrophages running around your body have your DNA, they are literally you, but it’s this weird relationship. Ahhh, I think it’s the most interesting topic in the world. And I’m super-curious to learn what we will know in 20 years’ time. It’s a very dynamic field, so much stuff is happening.
You are damning about the idea that you can boost your immune system. Why?In our society, selfimprovement is a thing; it sells a lot of stuff, but it is a flawed idea that you want a “boosted” immune system. People imagine that they can get like a rugby-player immune system that can smash faces and stuff. but what you want is a balanced immune system, one that knows exactly where to step and where to kick, and how hard. Like Covid: many people are dying of Covid because it can cause an overreaction of the immune system [called a cytokine storm]. So even if you could “boost” your immune system with stuff you buy in the supermarket – which you can’t, thank God – you wouldn’t want to do that without speaking to a doctor.
Will we emerge from the Covid era with a greater understanding of how our bodies fight disease and infections? I’m pessimistic, to be honest. Interest in it has heightened but all sorts of antivaccine conspiracy theorists are having the time of their lives. Once you learn what vaccines are and how they really work, it’s very hard to think that they’re a bad idea.
Has the popularity of the antivaccine movement surprised you?It’s just tragic. I don’t even want to kick down on anti-vaccine people, because it’s also affecting smart people. This is not a movement of idiots. Science and immunology gave us these life-changing wonders and some people can’t trust them. It’s sad, really.
What’s next for you and Kurzgesagt?We’ve many exciting projects starting next year that I can’t talk about yet: streaming stuff, bigger projects. But honestly, my favourite thing to do is the YouTube channel. I think I’m good at it, and it’s very fun. Then I might write another book. I have a few ideas, but writing this one was a horrible process. I hated it. Never write a book, Tim.
• Immuneby Philipp Dettmer is published by Hodder & Stoughton (£25). To support the Guardian and Observer order your copy at guardianbookshop.com. Delivery charges may apply
Self-improvement sells a lot of stuff, but it’s a flawed idea that you want a 'boosted' immune system