What can I do then?
A very important factor, in addition to adequate sleep, mental activity and social contacts, is definitely regular physical activity. This is scientifically proven. It even improves the course of the disease after neurological diseases, thus serving not only prevention but also recovery. Physical activity improves blood circulation in the brain, for example, influences important messenger substances in the brain such as the release of dopamine and serotonin, the so-called happiness hormones, and leads to an increased release of neurotrophins and growth factors such as the insulin-like growth factor IGF-1. This insulin-like growth factor is, amongst other things, crucial for the functioning of cell division and differentiation, particularly in muscle and bone tissue. Regular exercise not only has a preventive effect against physical brain diseases such as dementia or stroke, but also against mental illnesses such as depression or chronic fatigue. The risk of developing dementia is significantly reduced, if not completely prevented, by regular physical activity. The onset of cognitive degradation is often delayed for years, and the progression of those who are already ill can also be slowed down.

How much exercise does the brain need?
Ideally, at least 30 to 60 minutes a day, of which 2/3 as endurance training, 1/3 as high-intensity interval training (HIIT), strength training about twice a week and balance training once a week, the latter especially for older people. Children need plenty of exercise to ensure healthy development of their brains, so 60–90 minutes a day are recommended. In schools and kindergartens, we should do much more to achieve this, instead of reducing the number of sports lessons, as was recently reported. Sufficient exercise is the best prevention because overweight, inactive children often become sick adults.

How do you integrate these training sessions into your daily work?
By scheduling them on a fixed basis, like other appointments. I do long-distance triathlon and train for it every day. I am often asked how I can train regularly with my tight schedule. My answer: I achieve this performance in my professional life precisely because I do sport regularly. However, it’s not just the conscious planning that is key. The sport you choose should be fun, otherwise training is just another stress factor. But I guarantee that a lack of willpower will soon not be an issue because the joy of exercise takes over and you won’t want to give up your sports sessions.

Can employers also make it easier for their workforce to have more opportunities for physical activity and to get enough sleep?
This is actually very important as it helps to prevent many diseases that ultimately cost companies a lot of money. For example, I’ve introduced almost two-hour lunch breaks so my team members can play sport and have enough time to take a quick shower and eat afterwards. Of course they then have to work a little longer in the evening or start a little earlier in the morning. This is not possible everywhere, but just having a shower and changing room on the premises might motivate them to cycle to work or go jogging for lunch. It is essential for rest periods to be observed, and balanced healthy meals should be offered in the staff restaurant.

You mention healthy meals. What about nutrition? Is there such a thing as brain food?
Definitely! A Mediterranean diet with lots of protein and few bad carbohydrates also strengthens the brain. This includes lots of vegetables, nuts, olive oil, occasionally fish or meat, fruit and low-fat dairy products. Most people eat too many bad carbohydrates such as white bread, sweets, cakes, crisps and ready-made products. They don’t give the body anything it can use meaningfully.
Speaking of proteins: the widespread overly hyped protein powders, drinks and bars are never as good as natural proteins. Protein shakes only make sense if you have trained hard and cannot eat a protein-rich meal within 1 to 2 hours afterwards. Animal proteins such as eggs can be absorbed by the body very well, the “artificial” ones much less well. I myself eat one egg every day, sometimes even several, depending on how much I’ve exercised. By the way, we now know that the long frowned-upon eggs are anything but harmful.

And if we’re talking about dietary supplements: you encounter advertising for them almost every day, including drugs that are explicitly intended to improve brain health, for instance memory. Which of these makes sense?
Supplying the body with substances via supplements only makes sense if a deficiency has been determined by a lab analysis. I generally only prescribe a supplement in such cases – and such a deficiency is very rare. Exceptions are women of childbearing age who often have an iron deficiency or who should take folic acid supplements. People should be aware that there are also substances that are harmful in excess. Not all vitamins and minerals can be excreted from the body if they are taken excessively. The body stores them, and this can lead to harmful consequences. But people who follow a balanced diet as mentioned above, with fresh foods including fish and lean meat and preferably without convenience and fast food, will hardly ever have a vitamin or mineral deficiency.

What are your key findings for maintaining a healthy brain?

• Regular physical activity in the form of sport with a mix of endurance, interval, strength and balance training. It not only leads to better blood circulation in the brain, but also to the release of important messenger substances and the activation of important factors for healthy cell division and differentiation.
•  A healthy, balanced, high-protein diet with fresh foods and few “bad” carbohydrates, essentially equivalent to a Mediterranean diet. The body can use animal proteins, for example in eggs, much better than artificial proteins in powders, drinks or bars.
• Sufficient and healthy sleep, about 7 to 9 hours. The brain continues to work during this time, but in a different way than during the day. For example, it consolidates memories. If it does not get these sleep phases for a long time, it will impact on the person's health and well-being in all areas.
• Social contact and learning new content right into old age keep the brain going. In this way, new connections in the brain continue to form. Neuroplasticity is thus maintained, albeit at a lower level than in infancy or childhood.