Thomas Kühlein, Professor of General Practice in Erlangen, explains how evidence-based medicine can contribute to better healthcare at the 2026 GDNÄ conference.

Professor Kühlein, according to the conference programme, you will be speaking in Bremen about truth and science. That’s a broad topic – what exactly will you be discussing?
Evidence-based healthcare – in other words, medicine that is based on the best available research findings and the experience of practising doctors, whilst also taking the patient’s perspective into account. That’s how good medicine should be, I thought more than twenty years ago when, as a GP in a rural practice at the time, I undertook my first training in this area – and that’s still my view today. But unfortunately, evidence-based medicine is often misunderstood, misinterpreted or ignored. 

Where do you see this happening? 
For example, in the cancer screening programmes offered by health insurance funds for breast cancer, bowel cancer, skin cancer, cervical cancer, prostate cancer and, more recently, lung cancer. The aim of these screening programmes, as they are known in technical terms, is to detect tumours at an early stage. In other words, when they are often easily treatable and those affected have not yet experienced any symptoms. That is the theory. The reality observed in studies looks different. The risks and expected benefits for individuals are generally smaller than anticipated, and potential disadvantages due to so-called overdiagnosis are sometimes even more likely than the benefits. However, this is often not communicated fairly. Overall, specialised programmes for at-risk groups would probably be much more efficient.

© Uniklinik Erlangen.

The Institute of General Medicine is responsible for specialist research and teaching at Erlangen University Hospital. Here is an exterior view.

This is precisely what is currently being discussed in relation to skin cancer screening.
Yes, we expressly welcome this. Germany is the only country with a nationwide, non-risk-based skin cancer screening programme. Insured individuals aged 35 and over are entitled to this early detection examination every two years. As expected, the programme has led to an increase in the number of skin cancer diagnoses, but not to fewer people dying from skin cancer – the available studies show this very clearly. This is precisely what is referred to as overdiagnosis. It is therefore high time for a change of course: away from a one-size-fits-all approach, towards screening for people at high risk of skin cancer. This includes people with very fair skin as well as, for example, farm workers or road workers. Another advantage of the risk-adapted approach: if unnecessary screening tests are eliminated, doctors have more time for patients who are genuinely ill. 

Smaller screening programmes may also help to reduce healthcare costs. The federal government is currently searching almost desperately for further ways to save money. Where do you see the greatest potential? 
Firstly, in the planned primary care system. The project is included in the coalition agreement, and the government intends to introduce it gradually. According to the plan, those with statutory health insurance should first visit their GP when ill, who will then either provide treatment themselves or refer the patient to a specialist as appropriate. This could help avoid unnecessary medical costs. 

This requires a large number of GPs. But there is already a severe shortage of them everywhere.
In the meantime, chairs in general practice have been established at almost all medical faculties. These help ensure that students perceive general practice as an interesting subject right from the start. Of course, it takes time for these students to actually enter practice. Another approach is to relieve GPs of tasks that can be handled by other members of the primary care team. This has a lot to do with fee structures. Here too, a fair bit has already happened in recent years.

© Uniklinik Erlangen.

Together with his team at the Institute of General Medicine in Erlangen, Thomas Kühlen (top row, right) is investigating the scientific foundations of good patient care.

We’re still on the first cost-saving proposal. What’s next?
My second proposal aims to improve digital connectivity between doctors, patients, health insurance funds and other stakeholders in the healthcare system. An example: electronic patient records can prevent duplication of costly diagnostic tests and reduce laboratory costs; we just need to start using them consistently at last. And thirdly: evidence-based thinking and practice must be embedded even more firmly – in medical training and in doctors’ day-to-day work. Not everything that is statistically significant is also relevant. If the evidence suggests it, we can sometimes leave things out. In my experience, patients go along with this if I explain it to them properly. 

 That may apply to individuals. But do you believe that a large part of the population is ready for a culture of leaving things out?
No, something like that doesn’t happen overnight. Today, it is mainly older people who are open to such discussions, as they no longer wish to undergo every medically feasible treatment. This is not a question of money, but one that relates to our attitude towards life and the end of life. As a society, we tend to have a rather dysfunctional relationship with mortality. This fuels the obsession with what is medically possible and the over-provision in the healthcare system; we doctors should always be aware of this.  We play a key role in this system, and together with our patients we can make a real difference. Joint decision-making is crucial: scientifically sound, tailored to patients’ needs and, finally, well documented. 

Let’s return to the title of your GDNÄ lecture. What claim to truth can science make from the perspective of evidence-based medicine?
At best, science is an approximation of the truth. Its findings remain valid until they are refuted by new evidence. The type of studies used in evidence-based medicine never provides truths that are laws of nature. What I find particularly important in this context is that science can provide the best possible basis for decision-making, but nothing more. We ourselves must make the decisions and take responsibility for them. I will explain in Bremen how all this can contribute to better medicine.

Asymmetric organic catalysis? Nobel Laureate Benjamin List explains how he came up with this crazy idea and what it means for our future at the 2026 GDNÄ conference in Bremen.

Professor List, in December 2021 you were awarded the Nobel Prize in Chemistry. Has your life changed since then?
Yes, it has – especially at the beginning. TV appearances weren’t part of my normal daily routine before. Nor were the many public lectures, whether at ‘Jugend forscht’, the Kulturhaus Heidelberg or in university lecture theatres. The first two or three years were very intense. In the meantime, I’ve been able to get my life back to normal and finally have enough time again for my large research group at the institute in Mülheim. It’s not as if, as a Nobel laureate, you stop doing research.

What are you currently working on?
I’d like to highlight two projects. Firstly, we’re trying to remove the greenhouse gas CO2 from the atmosphere by breaking it down into O2 and C using sunlight and catalysts. The oxygen O2 returns to the atmosphere without any issues; what remains is carbon. This could be used as a kind of solar coal for all sorts of processes in the chemical industry. Surplus coal could be buried, for example in tunnels along the Rhine and Ruhr. The whole thing could help solve humanity’s energy problem and would be climate-neutral at the same time. We’re still facing a few tricky problems, but hopefully they’ll be solved in ten years’ time. Our idea isn’t entirely far-fetched; after all, CO2 splitting is already taking place on Mars, albeit only in small quantities. 

And your second project?
We’re currently setting up a company that produces pure fragrances. At the molecular level, fragrances usually consist of two variants, known as enantiomers. They fit together like a picture and its mirror image, but have biologically different effects. The original might smell of mint, for example, and the mirror image of caraway – together they make a strange mixture. In industrial production, therefore, the aim is to produce pure fragrances containing only one of these molecular twins. To date, this has only been possible using complex processes. With the help of our patents, production can be simplified and made cheaper. I think we’ll be able to start this year. I am a basic researcher, but getting to know the industrial world is exciting.

© David Ausserhofer

At work: Benjamin List leads a team of around forty researchers from all over the world. Teamwork is a top priority in the List research group.

You were awarded the Nobel Prize for the discovery of asymmetric organic catalysis. What makes this process so significant?
Catalysis as such is very, very important for our lives. Just one example: without the Haber-Bosch process, that classic example of catalysis, there would be no fertilisers. We wouldn’t then be eight billion people, but perhaps only four billion due to a lack of sufficient food. I consider catalysis to be humanity’s most important technology.  Overall, there have already been several Nobel Prizes for catalysis research, and almost all of them were for metallic catalysts. Unfortunately, these also have drawbacks: many of them are expensive, rare and, on top of that, toxic. In 1999, I experimented with a small molecule, the amino acid proline, and discovered that it not only acts as a catalyst but also specifically produces the desired enantiomer. When I published this in early 2000, it came as a huge surprise to the scientific community: an organic molecule found in the human body acts as a highly selective catalyst – incredible! 

You share the Nobel Prize with the Scottish-born US researcher David MacMillan, who arrived at similar results independently of you. Was the discovery in the air?
In hindsight, you could see it that way. David and I actually knew nothing about each other. We each made the crucial discoveries independently in 1999. When my very first proline experiment worked, I thought: Wow, this could be something big. Yet the idea itself wasn’t actually that new. Other chemists had tried it too. When the initial experimental results from the 1960s and 1970s weren’t really understood, interest in it waned. David MacMillan and I then tried a different approach and succeeded. Many chemists at the time rubbed their eyes in disbelief and asked: How could we have overlooked this?

@ David Ausserhofer

A scene in the laboratory of Benjamin List’s ‘Homogeneous Catalysis’ department at the Max Planck Institute for Coal Research in Mülheim.

Is organocatalysis used in industry today?
Yes, in many fields, including the production of medicines. One example is darunavir for the treatment of HIV. The active ingredient, a so-called protease inhibitor, prevents the AIDS virus from multiplying in infected people. The World Health Organisation has included it on the list of essential medicines.

Is more public funding needed for catalysis research?
Yes, that would be money well spent. At present, we are lagging behind in artificial intelligence, quantum and fusion technologies, far behind the US and China. Catalysis is not as popular, but it represents a major opportunity for Germany. We have a long tradition in this field and a great deal of expertise in the country. 

Let’s take a look back: how did you come to become a chemist?
It all began when I was eleven years old. Together with two friends, I had set up a small laboratory in a basement in Frankfurt; we bought the necessary chemicals from a local chemist. At that time, I wasn’t yet taking chemistry lessons. Later, I had a few gifted teachers who encouraged me. But by then my interest in the subject was already very strong, and no teacher could have steered me away from that path. 

The GDNÄ has its own youth organisation, the jGDNÄ. Is there anything you would advise young people interested in the natural sciences?
Follow your passion! Don’t let yourselves be swayed, even if your parents say: ‘I see you as a lawyer or a doctor.’ There are good career opportunities in the natural sciences, both in academia and in industry. The world has recognised how important research is. And it’s a stroke of luck if you’re interested in it. It gives me immense pleasure to be able to unlock a few of nature’s secrets and perhaps change the world in the process. 

On 19 September, you will be giving the public Nobel lecture on the topic of ‘Organocatalysis for our world’ at the GDNÄ meeting in Bremen. What prior knowledge is needed to follow your talk?
An interest in the subject should suffice. I try to speak as clearly as possible. 

What message do you want to convey to your audience?
Organocatalysis can be both basic research and application. Both are fascinating, and that is what I want to convey. And in doing so, I’d also like to promote the Max Planck Society a little. Its outstanding basic research is well known to many, but not everyone realises that it is also the most successful start-up organisation in this country. I have one more message: enthusiasm for what you do is important. Whether in research or in other areas of life. 

To conclude, may I ask you about a particular photo showing you standing on your hands with your legs crossed in the laboratory? How did that come about?
The photo was taken a few years before the Nobel Prize, during an interview with my fellow student Catarina Pietschmann, who works as a freelance journalist in Berlin. ‘You have to swim against the tide now and then,’ I’d said during the conversation, ‘maybe even stand on your head.’ That’s how the idea for the handstand in the lotus position came about. My wife was in the lab at the time; she held me up. I can’t manage a handstand on my own just yet. 

Do you practise yoga?
Yes, yoga is important to me for keeping my mind fresh. I’ve been doing it for many years, one to two hours a day and mostly without instruction. I’ve got the hang of it a bit now.