When it comes to our health, too many of us think that a medical diagnosis describes a static or worsening condition. We live our lives as though our ailments—our stiff knees or frayed nerves or failing eyesight—can only change in one direction: for the worse. Ellen J. Langer’s life’s work proves the fault in that logic. She has spent more than forty years testing the limiting effects of our negative assumptions as well as the healing power of being mindful—present in the moment and not distracted by memories or projections into the future. In The Mindful Body she unpacks her findings and boldly demonstrates how our thoughts and perspectives have the potential to shape our well-being.

Taking us into Langer’s trailblazing Harvard lab, The Mindful Body recounts many of her colorful experiments to illustrate the influence of mindfulness on how our bodies function, how we heal, and even how we age. In one study, Langer rigged eye charts so that participants would identify some of the smaller letters correctly right away, giving them the expectation that they could improve their overall eye test scores. And they did. In another, she showed that wounds heal faster when subjects are placed in rooms with accelerated clocks; when you think that time is passing faster, your body heals faster!

On the other hand, her work also reveals that discouraging health news can lead to a worsening physical state: She shows that learning you are pre-diabetic—even when only a fraction separates your blood sugar from a “normal” categorization—may actually play a part in the development of the disease.

A paradigm-shifting book by one of the great psychologists of the twenty-first century, The Mindful Body returns the control over our bodies back to us and reveals that a true understanding of health begins with our mindset.