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Jellyfish Age Backwards author does experiments on himself

Longevity — Nicklas Brendborg is a bestselling author with two books on how we can live longer. The inspiration comes from the animal kingdom, and from experiments on his own body. We visited him in the laboratory at the Center for Physical Activity Research (CFAS), where he is a PhD student.

»Good lord! I thought there was suddenly lightning out there.«

Two colleagues mumble in the office behind a pastel-coloured door at the Center for Physical Activity Research (CFAS), Rigshospitalet.

»It’s just me! Sorry, it’s just the camera flash out here, sorry.«

Nicklas Brendborg pokes his head into the office and raises his hand apologetically.

»Oh, it’s just Nicklas getting his photo taken,« a colleague laughs.

»Is it for the interview?« the other one asks.

Nicklas Brendborg nods.

»Oh, how exciting! Looking forward to reading it.«

Author and PhD student Nicklas Brendborg is 28 years old and already has two bestsellers behind him, Creatures of Habit [in Danish = ‘Vanedyr’] from 2023, and Jellyfish Age Backwards: Nature’s Secrets to Longevity, from 2021. In Jellyfish Age Backwards, he reviewed what the science says on how we can postpone old age. He taught his readers, for example, that flossing your teeth can prolong your life. And that bloodletting can be healthy — every now and again.

In his latest book, he describes how both streaming videos, and processed food, were created by giant industries to manipulate our instincts. We are creatures of habit, he writes. Victims of addictive super stimuli, that make us eat much more than we need, and to dive far deeper into our smartphones than we would like to.

Nicklas Brendborg has in recent years been all over the Danish media, and has been indiscriminately labelled a »star researcher« and a »young genius«. He has been particularly praised for his ability to communicate complex scientific findings in an easy-to-understand and humorous manner. Like by comparing the bad habits of humans with the oystercatcher bird’s irrational fascination with a fake, and unnaturally large, egg, leading it to abandon its own eggs.

I was brought up in the provinces. Where I come from, I think it's a bit too early in my research career to be called a 'star researcher' and that sort of thing.
Nicklas Brendborg

He is currently a PhD student at the TrygFonden’s Center for Physical Activity Research and at the University of Copenhagen. And when the University Post journalist and photographer meet up with him at his workplace, he says that his star status on Danish media will not affect his work.

»I was brought up in the provinces. Where I come from, I think it’s a bit too early in my research career to be called a ‘star researcher’ and that sort of thing,« says Nicklas Brendborg.

Of course, we are not the first people to visit Nicklas Brendborg at the Rigshospitalet in Copenhagen. When we ask for a guided tour, he takes a few minutes to consider the situation.

»It’s just because…« he begins, and taps his arm thoughtfully with his fingers.

»… I share an office with two other PhD students, and they are working right now. I also think there are people in the labs,« he says.

It is not because anyone has complained about the many journalists who have flocked to Nicklas Brendborg’s workplace in recent months, he says.

»People in here have been supportive and interested. Several of them have even bought my books as Christmas presents. But I just don’t want to disturb anyone working.«

Compliments from a guru

If you follow Nicklas Brendborg on social media, it becomes clear to you that his daily life is filled up with much more than the work at the Center for Physical Activity Research .

His calendar is full of lectures and interviews. But he insists that it is never too much. The worst thing he can imagine is getting bored.

He wrote his first book while still a master’s student of molecular biotechnology at the University of Copenhagen. It was praised and reviewed on the Danish media site Politiken by chief physician and professor Bente Klarlund, who gave the book five stars. She called Nicklas Brendborg a »genius« who »entertains you right until the last page without becoming superficial.«

Nicklas Brendborg appreciated the praise from Bente Klarlund. She is a popular health guru partly because of her readers’ letters section on the Politiken site, several TV appearances, and a large number of books on health.

»I thought that if Bente Klarlund liked my book, maybe there would be an opportunity to work for her. She is head of the Center for Physical Activity Research, where I think there are some really exciting things going on,« says Brendborg.

He reached out to Bente Klarlund and initially got a job as a research assistant at her centre, followed by a PhD position at the same place with Klarlund as principal supervisor.

The second book was completed at the same time as he was beginning his PhD.

»The plan was that I should finish it before I started my PhD, but it dragged on,« he says.

This meant that for a period of time he had to get up extra early so that he could work on the book before he arrived for work.

»I had a rule that I had to write at least an hour a day. After that, I could assess whether it was a good or a bad day. You know, some days it just flows, other days it just doesn’t come to you. As a rule, I was up so early that I showed up at the same time as the others,« says Brendborg.

For most people, life as a PhD student is demanding enough in itself. As a rule, a PhD student must complete a research project in three years. In addition, most PhD student are required to teach a certain number of hours. But Nicklas Brendborg has not yet had time to seriously consider all this.

When asked how on earth he can do it all, he answers:

»All the things I do are not equally difficult. I could, for example, just as easily sit here after work and do an interview with you, as I could go home and watch Netflix. I would not get much out of the latter anyway.«

He shrugs.

»I feel very privileged to have built a life where I get to do everything that I find exciting.«

Poor human cells

»Hey, don’t come in here!«

Nicklas Brendborg holds up his hand defensively when the University Post photographer tries to follow him into a sterile laboratory. You need to have a special lab coat and shoes so you don’t destroy the »poor human cells« that are so easily outcompeted by bacteria from the outside if they are not protected by special cupboards, explains Nicklas Brendborg.

Instead, we are allowed to look through a glass door while an enthusiastic Nicklas Brendborg points, gestures — and in a muted version — tells us how a special extraction cabinet pushes air away from the human cells.

»It is the opposite of a fume cupboard,« he says when he is out of the laboratory again.

In his books, Nicklas Brendborg has trawled through thousands of research articles on ageing in both humans and animals. He then outlined the connections between the different findings, and communicated it so that ordinary people could understand it.

»It all started from pure self-interest. At one point I thought it would be cool if I could share the knowledge I had gained to others, so that they do not have to sit and read everything I have been through,« he says.

Nicklas Brendborg has now moved away from the research articles and into the laboratories, where he has to do get his own hands dirty. And on human cells, as it happens.

»In my work on my books, I have sometimes come across questions that previous research has not been able to explain. It’s great to do the research yourself, and in this way help fill out some of the gaps in science,« he says.

A small piece of human thigh

So what is Nicklas Brendborg doing with the fragile human cells in the sterile laboratory?

He doesn’t talk about this part more than is absolutely necessary.

»I don’t quite know how much to say.«

He hesitates for a moment.

If you believe that life has a value in itself, why not let it last as long as possible?
Nicklas Brendborg

»We are working quite intensely on some results, where we hope to be first. In general, I can tell you that it’s about how aging affects both young and old muscle cells, and how it later affects the brain,« he says.

The specific work consists in first collecting muscle tissue samples, or biopsies, from both young and old people.

»You jab a huge needle into people’s thighs. It’s something we’re really good at here,« Nicklas Brendborg laughs and makes a grimace.

He had it done on himself a few months ago. This tiny human sacrifice in the name of science resembles a »small lump of mincemeat.«

»It wasn’t actually that bad, even though it looks quite uncomfortable. You get a local anaesthesia first,« he says.

When the muscle tissue is out, it is all about getting the cells to grow.

»We put a medium on top of them so that we can feed them with different things like sugars and things like that. And then we keep an eye on how they react, and whether they secrete something or other, so we can see if it has an effect,« he says and then stops abruptly.

He does not want to elaborate on exactly what effect. But it sounds as if Nicklas Brendborg’s research is a fledgling attempt to counteract aging. He would not immediately confirm that. But he dares to reveal that the research is about slowing down the aging of the brain.

Do you think it can be done?

»Yes, otherwise we wouldn’t have started.«

55 will be the new 35

Nicklas Brendborg is, in his own words, »extremely fascinated by aging.«

»All research indicates that the single biggest risk factor for deadly diseases like cancer, dementia and blood clots is aging. A 28-year-old like me, for example, has a significantly lower risk of contracting these diseases than someone of 80. Things like smoking obviously also increase the risk – but nothing at all like aging,« he says.

»If we find a way to slow down aging, we can hit all these diseases at once.«

By not growing old?

»Of course, it’s very optimistic to think that we’re no longer going to age. But if we can learn more about some of the key mechanisms that allow us to age, we might also be able to find ways to slow them down too,« says Brendborg, and adds:

»If we look at people who are 110 years old, they usually end up dying from the same things as everyone else – a blood clot, cancer, that sort of thing. But the point is that the diseases occur 20-30 years later. Why?

In the future, Nicklas Brendborg predicts that we will find methods to slow down aging, so that a 90-year-old will have a biological age of 70. 55 will be the new 35. And so on.

I ask why he thinks it is attractive to postpone old age, death. It is not the first time he has been asked about it, so he has an answer ready for us.

»Growing old is not a pretty picture. It’s actually quite gruesome. Of course we are going to die, but if we have the opportunity to extend our lives, and postpone the diseases we usually die from, why not do it?”

Nicklas Brendborg pauses for thought.

»If you believe that life has a value in itself, why not let it last as long as possible?«

Life of a lobster

It is not because Nicklas Brendborg has some kind of personal trauma, or fear of old age as such. But he wonders why there is such a big difference in how the different species of the Earth age and die. The ‘Jellyfish Age Backwards’ book got its name because jellyfish can simply physically evolve back to an earlier life stage.

»There are several examples of animals that do not undergo an actual aging process. The lobster, for example. It just keeps getting bigger and bigger, stronger and stronger, and more and more fertile. It has no physical decline during its life. One day it just gets so big that it can no longer fit inside its own body.«

Whoops. And then it dies. Without suffering from dementia or a bad hip.

Do you think it will be like this for people one day?

»It’s not inconceivable. But I don’t know if it will be in this generation, the next one, or in 500 years time,« says Nicklas Brendborg.

He is often portrayed as the man who is on a quest for eternal life.

In a Danish periodical newspaper Weekendavisen he is even quoted as wanting to become the longest-living person ever. This would have him breaking the current record of 122 years of age.

According to Nicklas Brendborg, however, the dream of an antidote to old age is not so much about his personal life trajectory.

»I hope that my knowledge of health and ageing rubs off on myself a bit. But I see a bigger picture. I would like to help a lot of people and contribute to our success in postponing the deadly diseases that result from aging in the future,« he says.

»As for myself, I have no idea. I could get hit by a bus tomorrow. I can get cancer, even though I have done everything to prevent it. No matter how healthy you live, you can always be unlucky.«

Drop your diet

In recent years, Nicklas Brendborg has gone to extremes to optimize his own health. He tested a diet, for example, that consisted solely of boiled potatoes, the world’s most filling food. He has also tried stone age diets, vegan diets, low carb, and just about every special diet you can imagine.

»But to be quite honest, I found that it doesn’t make much difference whether you follow an extreme diet or just make sure you eat lots of vegetables and as little processed food as possible,« he says.

He knows this partly because he has had the opportunity to test his own health on all conceivable parameters.

»I tend to quickly become fascinated by different health trends and then let my life be taken over by them for periods of time. Today I eat a normal, healthy diet, and my blood tests, my fitness, and my body fat percentage are all just fine.«

The only health trend Nicklas Brendborg currently follows is the ’80-20 principle’, as he calls it. He eats healthy, non-processed, food 80 per cent of the time. The rest of the time he allows himself to slack off with some fast food or sugar.

Jellyfish in the aquarium

Even though Nicklas Brendborg’s current interest is primarily in ensuring a longer life for his own species, he has a thing for animals. This is evident in his literature, where human ageing processes and habitual patterns are often spiced up with anecdotal comparisons to the animal kingdom.

»I don’t have animals myself. I reckoned it would be ‘on brand’ to have an aquarium with jellyfish. But then I found out that you cannot have them in an ordinary square aquarium. Jellyfish are so unintelligent that they get stuck and die if they swim into a corner. They simply can’t change direction,« he says.

Jellyfish might live forever, but it’s probably cooler to be a human.

We, too, are driven by irrational habits that cause us to act against our own best interests. By stuffing ourselves with empty calories, for example, or by bingeing on superficial TikTok reels.

But unlike jellyfish, we can learn. We can become aware of our unhealthy habits, and we can choose to take active action to change them. This is certainly the revolution that Nicklas Brendborg hopes to help start.

Shortly before Christmas, I chanced upon the young researcher in the small town of Støvring in northern Jutland, where he grew up. We had both gone home for a holiday. I myself am on the hunt for a yarn shop in the town, while the scientist is rushing through the streets to make an appointment with his favourite hairdresser.

Nicklas Brendborg has lived in Copenhagen for more than eight years. Maybe he is a creature of habit himself?