100 Jahre fit im Kopf

"A fit body without a fit mind only gets you halfway there."

Prof. Dr. Ingo Froböse in the foreword

Longevity doesn't stop at the neck.

We count our steps, track our blood sugar, lift weights, and eat more vegetables. But what good are those extra years if the right words suddenly escape you mid-conversation, with the quiet worry about dementia lingering in the background?

The good news comes from brain research: your brain stays adaptable well into old age. In one study, the hippocampus, the brain's memory center, grew by around two percent in 55- to 80-year-olds after a year of endurance training. And according to the 2024 Lancet Commission, roughly 45 percent of dementia cases worldwide are linked to factors we can actually influence. This book shows you exactly which ones, and how to change them in your everyday life.

SPIEGEL bestselling author Dr. Gerd Wirtz holds a doctorate in neurophysiology and has spent over twenty years making science accessible as a TV host and speaker. For this book, he analyzed nearly 300 sources, separated solid evidence from expensive promises, and developed a method that fits into any daily routine.

The method in three steps

• The Brain Longevity Check: Tasks and questions help you find out where you stand on body, mind, balance, and connection.
• Your profile: Your lowest score among the four areas reveals where your biggest lever lies. That's where you start, instead of trying to overhaul everything at once.
• The 4-Curve Formula: Your program in three phases over 66 days. According to a study by University College London, that's how long it takes on average for new habits to become automatic. The often-cited 21 days is a myth.

And after 66 days? Take the check a second time and compare your results to where you started. The vague worry about your own mind becomes a plan, and you can see in black and white what has changed.

You'll also discover,

• which tests are actually worth it and which you can skip: from the p-tau217 blood test to full-body MRIs to cognitive performance checks at the doctor's,
• why your brain clears out amyloid, the protein that builds up in Alzheimer's, during deep sleep,
• why constant rumination is linked to greater Alzheimer's-related buildup,
• why untreated hearing loss ranks among the biggest modifiable dementia risks,
• when omega-3 supplements actually help and why brain-training apps usually disappoint,
• how to tell harmless forgetfulness apart from real warning signs, and when it's worth seeing a doctor,
• what AI and brain implants can do today, and what's still science fiction.

For anyone who wants to still be reading the paper, making plans, and holding their own in conversation at 90. Whether you're 25 or 75 today: the earlier you start, the more reserves your brain builds up, and it keeps learning at any age. And for anyone who has seen firsthand, through their own parents, just how much depends on a clear mind.

Your brain isn't fate. You can start working on it today.